/* ========================================================================
   网课教学系统 - 前端样式
   主色：#6366f1（紫蓝色）
   背景：#f5f7fa
   卡片：#ffffff
   边框：#e8ecf1
   圆角：8px-12px
   阴影：0 2px 8px rgba(0,0,0,0.06)
   ======================================================================== */

:root {
    --course-primary: #6366f1;
    --course-primary-dark: #4f46e5;
    --course-primary-light: #818cf8;
    --course-primary-bg: #eef2ff;
    --course-bg: #f5f7fa;
    --course-card-bg: #ffffff;
    --course-border: #e8ecf1;
    --course-text: #1f2937;
    --course-text-muted: #6b7280;
    --course-text-light: #9ca3af;
    --course-radius-sm: 8px;
    --course-radius: 10px;
    --course-radius-lg: 12px;
    --course-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    --course-shadow-hover: 0 6px 20px rgba(99, 102, 241, 0.15);
    --course-shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.08);
    --course-transition: all 0.25s ease;
    --course-font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
        sans-serif;
}

/* ==================== 通用容器 ==================== */

.course-list-page,
.course-detail-page,
.course-player-page,
.my-courses-page {
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-bg);
    min-height: 60vh;
    padding: 24px 0 48px;
}

.course-list-page .container,
.course-detail-page .container,
.course-player-page .container,
.my-courses-page .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

/* ==================== 页面头部 ==================== */

.course-page-header {
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--course-border);
}

.course-page-header h1 {
    font-size: 28px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0 0 8px;
    line-height: 1.3;
}

.course-page-header p {
    font-size: 14px;
    color: var(--course-text-muted);
    margin: 0;
}

/* 分类筛选页 */
.course-cat-back {
    display: inline-block;
    margin: 0 0 12px;
    font-size: 13px;
    color: var(--course-text-muted);
    text-decoration: none;
}

.course-cat-back:hover {
    color: var(--course-primary);
}

.course-cat-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 14px;
}

.cat-tag-count {
    display: inline-block;
    margin-left: 6px;
    padding: 1px 7px;
    font-size: 11px;
    line-height: 1.4;
    border-radius: 8px;
    background: rgba(99, 102, 241, 0.12);
    color: var(--course-primary);
}

.cat-tag.active .cat-tag-count {
    background: rgba(255, 255, 255, 0.25);
    color: #fff;
}

/* ==================== 搜索与筛选 ==================== */

.course-filters {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 24px;
    padding: 16px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    box-shadow: var(--course-shadow);
}

.course-search-form {
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1;
    min-width: 240px;
    max-width: 420px;
}

.course-search-input {
    flex: 1;
    height: 38px;
    padding: 0 14px;
    font-size: 14px;
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    outline: none;
    transition: var(--course-transition);
}

.course-search-input:focus {
    border-color: var(--course-primary);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

.course-categories {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.cat-tag {
    display: inline-flex;
    align-items: center;
    height: 32px;
    padding: 0 14px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
    text-decoration: none;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: 16px;
    transition: var(--course-transition);
    white-space: nowrap;
}

.cat-tag:hover {
    color: var(--course-primary);
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
}

.cat-tag.active {
    color: #fff;
    background: var(--course-primary);
    border-color: var(--course-primary);
}

/* ==================== 课程网格 ==================== */

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}

.course-card {
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    overflow: hidden;
    box-shadow: var(--course-shadow);
    transition: var(--course-transition);
    display: flex;
    flex-direction: column;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--course-shadow-hover);
    border-color: var(--course-primary-light);
}

.course-card-link {
    display: block;
    text-decoration: none;
    color: inherit;
    height: 100%;
}

.course-card-cover {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
}

.course-card-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}

.course-card:hover .course-card-cover img {
    transform: scale(1.06);
}

.course-cover-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
}

.course-cover-placeholder .cover-icon,
.course-cover-placeholder {
    font-size: 64px;
    line-height: 1;
    color: var(--course-primary-light);
    text-align: center;
}

.course-price-tag {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 600;
    color: #fff;
    background: rgba(99, 102, 241, 0.92);
    border-radius: 12px;
    backdrop-filter: blur(4px);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15);
}

.course-price-tag s {
    opacity: 0.7;
    margin-right: 4px;
    font-weight: 400;
}

.course-free-tag {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 600;
    color: #fff;
    background: rgba(34, 197, 94, 0.92);
    border-radius: 12px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15);
}

.course-card-body {
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.course-card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text);
    margin: 0;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
    min-height: 2.8em;
}

.course-card-desc {
    font-size: 13px;
    color: var(--course-text-muted);
    margin: 0;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
    min-height: 2.4em;
}

.course-card-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    margin-top: auto;
    padding-top: 8px;
    border-top: 1px dashed var(--course-border);
    font-size: 12px;
    color: var(--course-text-light);
}

.course-card-meta .lesson-count::before {
    content: "▶";
    margin-right: 4px;
    color: var(--course-primary-light);
    font-size: 10px;
}

.course-card-meta .course-cat {
    padding: 2px 8px;
    background: var(--course-primary-bg);
    color: var(--course-primary);
    border-radius: 10px;
    font-weight: 500;
}

/* ==================== 分页 ==================== */

.course-pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 6px;
    margin: 32px 0;
}

.page-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
    padding: 0 12px;
    font-size: 14px;
    font-weight: 500;
    color: var(--course-text-muted);
    text-decoration: none;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    transition: var(--course-transition);
}

.page-btn:hover {
    color: var(--course-primary);
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
}

.page-btn.active {
    color: #fff;
    background: var(--course-primary);
    border-color: var(--course-primary);
    cursor: default;
}

/* ==================== 空状态 ==================== */

.course-empty {
    text-align: center;
    padding: 64px 20px;
    background: var(--course-card-bg);
    border: 1px dashed var(--course-border);
    border-radius: var(--course-radius-lg);
    color: var(--course-text-light);
}

.course-empty .empty-icon {
    font-size: 72px;
    line-height: 1;
    margin-bottom: 16px;
    opacity: 0.6;
}

.course-empty p {
    font-size: 15px;
    margin: 0;
}

/* ==================== 权限提示 ==================== */

.user-perm-info {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    margin: 24px 0;
    padding: 12px 16px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    box-shadow: var(--course-shadow);
}

.perm-badge {
    display: inline-flex;
    align-items: center;
    height: 26px;
    padding: 0 10px;
    font-size: 12px;
    font-weight: 600;
    border-radius: 13px;
    border: 1px solid transparent;
}

.perm-badge.perm-allowed {
    color: #15803d;
    background: #dcfce7;
    border-color: #bbf7d0;
}

.perm-badge.perm-denied {
    color: #b91c1c;
    background: #fee2e2;
    border-color: #fecaca;
}

.perm-badge.perm-limit {
    color: #c2410c;
    background: #ffedd5;
    border-color: #fed7aa;
}

.perm-badge.perm-discount {
    color: #1d4ed8;
    background: #dbeafe;
    border-color: #bfdbfe;
}

.perm-badge.perm-free {
    color: #7e22ce;
    background: #f3e8ff;
    border-color: #e9d5ff;
}

.perm-badge.perm-unlimited {
    color: #15803d;
    background: #dcfce7;
    border-color: #bbf7d0;
}

.perm-badge.perm-remaining {
    color: #1d4ed8;
    background: #e0f2fe;
    border-color: #bae6fd;
}

/* ==================== 课程详情页 ==================== */

.course-detail-page {
    padding: 24px 0 64px;
}

.course-detail-header {
    display: flex;
    gap: 24px;
    margin-bottom: 32px;
    padding: 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

.course-detail-cover {
    flex: 0 0 320px;
    width: 320px;
    height: 200px;
    border-radius: var(--course-radius);
    overflow: hidden;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
    flex-shrink: 0;
}

.course-detail-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.course-detail-cover .course-cover-placeholder {
    font-size: 80px;
}

.course-detail-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 12px;
    min-width: 0;
}

.course-detail-info h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0;
    line-height: 1.3;
}

.course-detail-info .course-detail-desc {
    font-size: 14px;
    color: var(--course-text-muted);
    line-height: 1.6;
    margin: 0;
}

.course-detail-info .course-detail-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    font-size: 13px;
    color: var(--course-text-light);
    margin-top: 4px;
}

.course-detail-info .course-detail-meta span {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.course-detail-info .course-price-info {
    display: flex;
    align-items: baseline;
    gap: 8px;
    margin-top: 8px;
}

.course-detail-info .price-current {
    font-size: 24px;
    font-weight: 700;
    color: var(--course-primary);
}

.course-detail-info .price-original {
    font-size: 14px;
    color: var(--course-text-light);
    text-decoration: line-through;
}

.course-detail-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 12px;
}

.course-detail-actions .btn {
    height: 42px;
    padding: 0 24px;
    font-size: 14px;
    font-weight: 600;
    border-radius: var(--course-radius-sm);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: var(--course-transition);
    cursor: pointer;
    border: 1px solid transparent;
}

.course-detail-actions .btn-primary {
    background: var(--course-primary);
    color: #fff;
    border-color: var(--course-primary);
}

.course-detail-actions .btn-primary:hover {
    background: var(--course-primary-dark);
    border-color: var(--course-primary-dark);
}

.course-detail-actions .btn-outline {
    background: transparent;
    color: var(--course-primary);
    border-color: var(--course-primary-light);
}

.course-detail-actions .btn-outline:hover {
    background: var(--course-primary-bg);
}

/* 进度条 */
.progress-bar-wrapper {
    margin: 16px 0;
    padding: 16px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.progress-bar-wrapper .progress-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
    font-size: 13px;
    color: var(--course-text-muted);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--course-bg);
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar .progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--course-primary) 0%, var(--course-primary-light) 100%);
    border-radius: 4px;
    transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.progress-text {
    font-size: 13px;
    font-weight: 600;
    color: var(--course-primary);
}

/* 课时列表 */
.lesson-list {
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
    overflow: hidden;
}

.lesson-list .lesson-list-title {
    padding: 16px 20px;
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text);
    border-bottom: 1px solid var(--course-border);
    background: var(--course-bg);
    margin: 0;
}

.lesson-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    border-bottom: 1px solid var(--course-border);
    transition: var(--course-transition);
    text-decoration: none;
    color: inherit;
}

.lesson-item:last-child {
    border-bottom: none;
}

.lesson-item:hover {
    background: var(--course-primary-bg);
}

.lesson-item .lesson-index {
    flex: 0 0 28px;
    width: 28px;
    height: 28px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 600;
    color: var(--course-text-muted);
    background: var(--course-bg);
    border-radius: 50%;
}

.lesson-item .lesson-title {
    flex: 1;
    font-size: 14px;
    color: var(--course-text);
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.lesson-item .lesson-status {
    flex-shrink: 0;
    font-size: 13px;
    color: var(--course-text-light);
}

.lesson-item .lesson-free-flag {
    flex-shrink: 0;
    padding: 2px 8px;
    font-size: 11px;
    font-weight: 600;
    color: #15803d;
    background: #dcfce7;
    border-radius: 10px;
}

.lesson-item.locked {
    opacity: 0.65;
    cursor: not-allowed;
}

.lesson-item.locked .lesson-index {
    color: var(--course-text-light);
}

.lesson-item.locked .lesson-title {
    color: var(--course-text-light);
}

.lesson-item.locked .lesson-status::before {
    content: "🔒";
    margin-right: 4px;
}

.lesson-item.completed .lesson-status::before {
    content: "✓";
    color: #16a34a;
    font-weight: 700;
    margin-right: 4px;
}

.lesson-item.completed .lesson-index {
    background: #dcfce7;
    color: #15803d;
}

/* ==================== 播放页 ==================== */

.course-player-page {
    padding: 16px 0 48px;
}

.course-player-page .container {
    max-width: 1400px;
}

.course-player-page .player-layout {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.player-main {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.player-video {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    background: #000;
    border-radius: var(--course-radius-lg);
    overflow: hidden;
    box-shadow: var(--course-shadow-lg);
}

.player-video video {
    width: 100%;
    height: 100%;
    display: block;
    background: #000;
}

.player-video .player-video-placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--course-text-light);
    font-size: 14px;
    background: #1f2937;
}

.player-content {
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    padding: 20px;
    box-shadow: var(--course-shadow);
}

.player-content h2 {
    font-size: 18px;
    font-weight: 600;
    margin: 0 0 12px;
    color: var(--course-text);
}

.player-content .player-lesson-content {
    font-size: 14px;
    line-height: 1.7;
    color: var(--course-text-muted);
}

.player-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    box-shadow: var(--course-shadow);
}

.player-nav-right {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.free-view-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    height: 34px;
    padding: 0 14px;
    font-size: 12px;
    font-weight: 600;
    color: #c2410c;
    background: #fff7ed;
    border: 1px solid #fed7aa;
    border-radius: 17px;
    white-space: nowrap;
}

.player-nav .nav-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    height: 38px;
    padding: 0 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
    text-decoration: none;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    transition: var(--course-transition);
}

.player-nav .nav-btn:hover:not(.disabled) {
    color: var(--course-primary);
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
}

.player-nav .nav-btn.disabled {
    opacity: 0.45;
    cursor: not-allowed;
    pointer-events: none;
}

.player-complete-btn {
    height: 38px;
    padding: 0 20px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: var(--course-primary);
    border: 1px solid var(--course-primary);
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.player-complete-btn:hover {
    background: var(--course-primary-dark);
    border-color: var(--course-primary-dark);
}

.player-complete-btn.completed {
    background: #16a34a;
    border-color: #16a34a;
    cursor: default;
}

.player-sidebar {
    flex: 0 0 300px;
    width: 300px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
    overflow: hidden;
    position: sticky;
    top: 16px;
    max-height: calc(100vh - 32px);
    display: flex;
    flex-direction: column;
}

.player-sidebar .sidebar-header {
    padding: 16px;
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text);
    border-bottom: 1px solid var(--course-border);
    background: var(--course-bg);
}

.sidebar-lesson-list {
    flex: 1;
    overflow-y: auto;
    padding: 8px 0;
}

.sidebar-lesson-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 16px;
    text-decoration: none;
    color: var(--course-text-muted);
    font-size: 13px;
    border-left: 3px solid transparent;
    transition: var(--course-transition);
    cursor: pointer;
}

.sidebar-lesson-item:hover {
    background: var(--course-primary-bg);
    color: var(--course-primary);
}

.sidebar-lesson-item .sidebar-lesson-index {
    flex: 0 0 22px;
    width: 22px;
    height: 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    font-weight: 600;
    background: var(--course-bg);
    border-radius: 50%;
}

.sidebar-lesson-item .sidebar-lesson-title {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.sidebar-lesson-item .sidebar-lesson-status {
    flex-shrink: 0;
    font-size: 12px;
}

.sidebar-lesson-item.completed .sidebar-lesson-status::before {
    content: "✓";
    color: #16a34a;
    font-weight: 700;
}

.sidebar-lesson-item.current {
    background: var(--course-primary-bg);
    color: var(--course-primary);
    border-left-color: var(--course-primary);
    font-weight: 600;
}

.sidebar-lesson-item.current .sidebar-lesson-index {
    background: var(--course-primary);
    color: #fff;
}

.sidebar-lesson-item.locked {
    opacity: 0.6;
    cursor: not-allowed;
}

.sidebar-lesson-item.locked .sidebar-lesson-status::before {
    content: "🔒";
    font-size: 11px;
}

/* ==================== 我的学习页 ==================== */

.my-courses-page {
    padding: 24px 0 64px;
}

.my-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.my-stats .stat-card {
    padding: 20px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.my-stats .stat-card .stat-label {
    font-size: 13px;
    color: var(--course-text-muted);
}

.my-stats .stat-card .stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--course-primary);
    line-height: 1.2;
}

.my-stats .stat-card .stat-sub {
    font-size: 12px;
    color: var(--course-text-light);
}

.my-course-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.my-course-list-section {
    margin-bottom: 36px;
}

.my-course-list-section h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--course-text);
    margin: 0 0 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--course-primary);
    display: inline-block;
}

.my-course-card {
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    overflow: hidden;
    box-shadow: var(--course-shadow);
    transition: var(--course-transition);
    display: flex;
    flex-direction: column;
}

.my-course-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--course-shadow-hover);
    border-color: var(--course-primary-light);
}

.my-course-card a {
    text-decoration: none;
    color: inherit;
    display: block;
}

.my-course-card .my-course-cover {
    position: relative;
    width: 100%;
    height: 160px;
    overflow: hidden;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 100%);
}

.my-course-card .my-course-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.my-course-card .my-course-cover .course-cover-placeholder {
    font-size: 56px;
}

.my-course-card .my-course-body {
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.my-course-card .my-course-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text);
    margin: 0;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.my-course-card .my-course-progress {
    margin-top: 4px;
}

.my-course-card .my-course-progress .progress-bar {
    height: 6px;
}

.my-course-card .my-course-progress .progress-info {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: var(--course-text-light);
    margin-top: 6px;
}

/* ==================== 通用按钮（搜索栏等） ==================== */

.course-filters .btn-primary {
    height: 38px;
    padding: 0 16px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: var(--course-primary);
    border: 1px solid var(--course-primary);
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.course-filters .btn-primary:hover {
    background: var(--course-primary-dark);
    border-color: var(--course-primary-dark);
}

/* ==================== 课程首页（左侧栏 + 轮播 + 卡片流） ==================== */

.courses-home {
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-bg);
    min-height: 60vh;
}

/* 左右分栏：左侧分类导航（常驻） + 右侧主内容 */
.courses-home__inner {
    display: flex;
    align-items: flex-start;
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 24px 16px 48px;
}

/* 左侧分类导航（深色竖排） */
.course-sidebar {
    flex: 0 0 240px;
    width: 240px;
    position: sticky;
    top: 20px;
    align-self: flex-start;
    background: linear-gradient(165deg, #1f2937 0%, #111827 55%, #312e81 100%);
    border-radius: var(--course-radius-lg);
    color: #e5e7eb;
    overflow: hidden;
    box-shadow: var(--course-shadow-lg);
}

.course-sidebar__all {
    display: flex;
    align-items: center;
    gap: 10px;
    height: 52px;
    padding: 0 20px;
    font-size: 15px;
    font-weight: 600;
    color: #fff;
    text-decoration: none;
    background: linear-gradient(90deg, #7c3aed, #6366f1);
}

.course-sidebar__all:hover {
    color: #fff;
}

.course-sidebar__all-icon {
    font-size: 18px;
}

.course-sidebar__group {
    padding: 6px 14px 0;
}

.course-sidebar__group-head {
    display: flex;
    align-items: center;
    gap: 4px;
}

.course-sidebar__group-head-link {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 9px 10px;
    border-radius: var(--course-radius-sm);
    color: var(--course-sidebar-text, #cbd5e1);
    text-decoration: none;
    transition: var(--course-transition);
}

.course-sidebar__group-head-link:hover {
    background: rgba(255, 255, 255, 0.06);
    color: #fff;
}

.course-sidebar__group-head.active .course-sidebar__group-head-link {
    color: #fff;
}

.course-sidebar__group-head-name {
    flex: 1;
    font-size: 14px;
    font-weight: 600;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.course-sidebar__group-head-meta {
    display: flex;
    align-items: center;
    gap: 8px;
}

.course-sidebar__caret-btn {
    flex: none;
    width: 26px;
    height: 26px;
    border: none;
    background: transparent;
    color: #8b96a8;
    font-size: 11px;
    line-height: 1;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    transition: transform 0.25s ease, color 0.2s ease, background 0.2s ease;
}

.course-sidebar__caret-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.course-sidebar__group-head.active .course-sidebar__caret-btn,
.course-sidebar__caret-btn.active {
    transform: rotate(180deg);
    color: #fff;
}

.course-sidebar__group-body {
    display: none;
    padding: 4px 10px 8px 10px;
}

.course-sidebar__group-body.open {
    display: block;
}

/* 横排排列（后台「分类排列方式=横排」时启用） */
.course-sidebar--horizontal .course-sidebar__group-body.open {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.course-sidebar--horizontal .course-sidebar__sub {
    padding: 6px 12px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.05);
}

.course-sidebar__course {
    position: relative;
    padding-left: 18px;
    font-size: 12.5px;
}

.course-sidebar__course::before {
    content: "▪";
    position: absolute;
    left: 6px;
    color: var(--course-primary-light);
    font-size: 9px;
}

.course-sidebar__sub {
    display: block;
    padding: 7px 10px;
    font-size: 13px;
    color: var(--course-sidebar-text, #a7b1c2);
    text-decoration: none;
    border-radius: 6px;
    transition: var(--course-transition);
}

.course-sidebar__sub:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.06);
}

.course-sidebar__sub.active {
    color: #fff;
    background: rgba(99, 102, 241, 0.35);
}

/* 单层分类：整行链接 + 数量角标 */
.course-sidebar__flat {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 9px 12px;
    margin: 2px 0;
    border-radius: var(--course-radius-sm);
}

.course-sidebar__flat-name {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.course-sidebar__flat-count {
    flex: none;
    font-size: 11px;
    line-height: 1;
    color: #94a3b8;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 10px;
    padding: 3px 8px;
}

.course-sidebar__flat.active .course-sidebar__flat-count {
    color: #fff;
    background: rgba(255, 255, 255, 0.25);
}

.course-sidebar__perm {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin: 16px 18px 0;
}

/* 右侧主内容 */
.course-main {
    flex: 1;
    min-width: 0;
}

/* 首页卡片网格：桌面一行约 4 张 */
.courses-home .course-grid {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 18px;
}

/* 轮播 Banner（右侧主内容顶部，圆角卡片） */
.course-banner {
    position: relative;
    height: 320px;
    border-radius: var(--course-radius-lg);
    overflow: hidden;
    margin-bottom: 24px;
    box-shadow: var(--course-shadow-lg);
    background: linear-gradient(120deg, #6366f1, #9333ea, #ec4899);
}

.course-banner__track {
    position: relative;
    height: 100%;
}

.course-banner__slide {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0;
    transition: opacity 0.6s ease;
    display: flex;
    align-items: center;
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    z-index: 1;
}

.course-banner__slide.active {
    opacity: 1;
}

/* 纯图片轮播：隐藏文字时整张图可点击跳转 */
.course-banner__slide--img {
    background-size: cover;
    background-position: center;
}

.course-banner__mask {
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, rgba(15, 23, 42, 0.92) 0%, rgba(15, 23, 42, 0.6) 40%, rgba(15, 23, 42, 0.25) 100%);
}

.course-banner__content {
    position: relative;
    z-index: 1;
    max-width: 720px;
    padding: 40px 48px;
    color: #fff;
}

.course-banner__subtitle {
    display: inline-block;
    padding: 4px 12px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: rgba(124, 58, 237, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 16px;
    margin-bottom: 14px;
}

.course-banner__title {
    font-size: 40px;
    font-weight: 800;
    line-height: 1.2;
    margin: 0 0 10px;
    text-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

.course-banner__desc {
    font-size: 14px;
    line-height: 1.6;
    color: #e5e7eb;
    margin: 0 0 20px;
    max-height: 3.2em;
    overflow: hidden;
}

.course-banner__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.course-banner__btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 15px;
    padding: 10px 26px;
    border-radius: 24px;
    border: none;
    font-weight: 600;
    text-decoration: none;
    transition: var(--course-transition);
    cursor: pointer;
}

.course-banner__btn--solid {
    background: #fff;
    color: #1f2937;
}

.course-banner__btn--solid:hover {
    background: #e6e9ff;
    color: #1f2937;
}

.course-banner__btn--ghost {
    background: rgba(255, 255, 255, 0.15);
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.5);
}

.course-banner__btn--ghost:hover {
    background: rgba(255, 255, 255, 0.28);
    color: #fff;
}

.course-banner__nav {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: 3;
    width: 38px;
    height: 38px;
    border: none;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    color: #fff;
    font-size: 15px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--course-transition);
    backdrop-filter: blur(4px);
}

.course-banner__nav:hover {
    background: rgba(255, 255, 255, 0.4);
}

.course-banner__prev {
    left: 16px;
}

.course-banner__next {
    right: 16px;
}

.course-banner__indicators {
    position: absolute;
    bottom: 16px;
    right: 36px;
    z-index: 3;
    display: flex;
    gap: 8px;
}

.course-banner__dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: var(--course-transition);
}

.course-banner__dot.active {
    background: #fff;
    width: 24px;
    border-radius: 6px;
}

/* 搜索 + 分类筛选条 */
.course-toolbar {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 28px;
    padding: 16px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    box-shadow: var(--course-shadow);
}

.course-toolbar__main {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

/* 权限徽章：横排居中 */
.course-toolbar__perm {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    padding-top: 12px;
    border-top: 1px dashed var(--course-border);
}

.course-toolbar .course-search-form {
    flex: 1;
    min-width: 240px;
    max-width: 420px;
}

/* 课程模块 */
.course-module {
    margin-bottom: 40px;
}

.course-module__head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 18px;
}

.course-module__title {
    font-size: 22px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0;
    padding-left: 12px;
    border-left: 4px solid var(--course-primary);
    line-height: 1.3;
}

.course-module__count {
    font-size: 13px;
    color: var(--course-text-light);
}

/* ==================== 响应式 ==================== */

@media (max-width: 1024px) {
    .course-player-page .player-layout {
        flex-direction: column;
    }

    .player-sidebar {
        flex: 0 0 auto;
        width: 100%;
        max-height: 360px;
        position: static;
    }

    .course-detail-cover {
        flex: 0 0 260px;
        width: 260px;
        height: 160px;
    }
}

@media (max-width: 768px) {
    .course-list-page,
    .course-detail-page,
    .course-player-page,
    .my-courses-page {
        padding: 16px 0 32px;
    }

    .course-page-header h1 {
        font-size: 22px;
    }

    .course-filters {
        flex-direction: column;
        align-items: stretch;
    }

    .course-search-form {
        max-width: none;
        width: 100%;
    }

    .course-categories {
        overflow-x: auto;
        flex-wrap: nowrap;
        padding-bottom: 4px;
        -webkit-overflow-scrolling: touch;
    }

    .cat-tag {
        flex-shrink: 0;
    }

    /* 网格变单列 */
    .course-grid,
    .my-course-list {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .course-card-cover {
        height: 180px;
    }

    /* 详情页头部纵向排列 */
    .course-detail-header {
        flex-direction: column;
        gap: 16px;
        padding: 16px;
    }

    .course-detail-cover {
        flex: 0 0 auto;
        width: 100%;
        height: 180px;
    }

    .course-detail-info h1 {
        font-size: 20px;
    }

    .course-detail-actions .btn {
        flex: 1;
    }

    /* 播放页：隐藏侧边栏，由垂直布局替代 */
    .player-sidebar {
        max-height: 280px;
    }

    .player-nav {
        flex-wrap: wrap;
    }

    .player-nav .nav-btn {
        flex: 1;
        justify-content: center;
    }

    /* 我的学习统计变单列 */
    .my-stats {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .course-page-header h1 {
        font-size: 20px;
    }

    .my-stats {
        grid-template-columns: 1fr;
    }

    .course-card-body {
        padding: 12px;
    }

    .course-card-title {
        font-size: 15px;
    }

    .player-content,
    .player-nav {
        padding: 14px;
    }

    .player-complete-btn,
    .player-nav .nav-btn {
        padding: 0 14px;
        font-size: 12px;
    }
}

/* ==================== 流媒体播放支持 ==================== */

/* 播放器容器（player 页 player-wrapper 适配） */
.course-player-page .player-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    background: #000;
    border-radius: var(--course-radius-lg);
    overflow: hidden;
    box-shadow: var(--course-shadow-lg);
}

.course-player-page .player-wrapper .video-container {
    position: relative;
    width: 100%;
    height: 100%;
}

.course-player-page .video-player {
    width: 100%;
    height: 100%;
    display: block;
    background: #000;
    object-fit: contain;
}

/* 直播标识 */
.live-badge {
    position: absolute;
    top: 12px;
    left: 12px;
    z-index: 10;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    background: rgba(220, 38, 38, 0.9);
    color: #fff;
    font-size: 12px;
    font-weight: 600;
    border-radius: 20px;
    backdrop-filter: blur(4px);
    animation: live-pulse 2s ease-in-out infinite;
}

@keyframes live-pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* 视频类型标签 */
.video-type-badge {
    display: inline-block;
    margin-left: 8px;
    padding: 2px 8px;
    font-size: 12px;
    font-weight: 500;
    color: var(--course-primary);
    background: var(--course-primary-bg);
    border: 1px solid var(--course-primary-light);
    border-radius: 12px;
    vertical-align: middle;
}

/* 播放器错误提示 */
.player-error {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    color: #fff;
    font-size: 14px;
    background: rgba(0, 0, 0, 0.85);
    z-index: 20;
    padding: 20px;
    text-align: center;
}

.player-error::before {
    content: '\26A0';
    font-size: 36px;
    margin-bottom: 8px;
}

/* 侧边栏课时直播标识 */
.sidebar-lesson-item .lesson-live-icon {
    color: #dc2626;
    font-size: 10px;
    margin-left: 4px;
}

/* ========================================================================
   课时播放页 - 美化样式（v2）
   ======================================================================== */

/* ---------- 面包屑 ---------- */
.course-player-page .player-breadcrumb {
    font-size: 13px;
    color: var(--course-text-muted);
    margin-bottom: 12px;
    padding: 8px 0;
    display: flex;
    align-items: center;
    gap: 6px;
}

.course-player-page .crumb-link {
    color: var(--course-text-muted);
    text-decoration: none;
    transition: var(--course-transition);
}

.course-player-page .crumb-link:hover {
    color: var(--course-primary);
}

.course-player-page .crumb-sep {
    opacity: 0.5;
}

.course-player-page .crumb-current {
    color: var(--course-text);
    font-weight: 500;
}

/* ---------- 视频占位符 ---------- */
.course-player-page .player-video-placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #1f2937;
    color: #9ca3af;
}

.course-player-page .placeholder-inner {
    text-align: center;
}

.course-player-page .placeholder-icon {
    font-size: 48px;
    margin-bottom: 12px;
    opacity: 0.5;
}

/* ---------- 直播徽章 ---------- */
.course-player-page .live-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    position: absolute;
    top: 12px;
    left: 12px;
    z-index: 5;
    padding: 5px 12px;
    font-size: 12px;
    font-weight: 600;
    color: #fff;
    background: rgba(220, 38, 38, 0.9);
    border-radius: 16px;
    backdrop-filter: blur(4px);
}

.course-player-page .live-dot {
    width: 7px;
    height: 7px;
    background: #fff;
    border-radius: 50%;
    animation: course-live-pulse 1.5s ease-in-out infinite;
}

@keyframes course-live-pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

/* ---------- 课时头部 ---------- */
.course-player-page .lesson-header {
    margin-bottom: 16px;
}

.course-player-page .lesson-title {
    font-size: 20px;
    font-weight: 700;
    margin: 0;
    color: var(--course-text);
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
    letter-spacing: -0.01em;
}

.course-player-page .video-type-badge {
    display: inline-flex;
    align-items: center;
    padding: 2px 10px;
    font-size: 11px;
    font-weight: 600;
    color: #6366f1;
    background: #eef2ff;
    border-radius: 10px;
    border: 1px solid #e0e7ff;
}

/* ---------- 进度条 ---------- */
.course-player-page .course-progress-section {
    margin-bottom: 16px;
    padding: 14px 18px;
    background: var(--course-bg);
    border-radius: var(--course-radius);
    border: 1px solid var(--course-border);
}

.course-player-page .progress-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
    font-size: 13px;
    color: var(--course-text-muted);
}

.course-player-page .progress-text {
    font-weight: 700;
    color: var(--course-primary);
}

.course-player-page .progress-bar {
    width: 100%;
    height: 8px;
    background: var(--course-border);
    border-radius: 4px;
    overflow: hidden;
}

.course-player-page .progress-bar-inner {
    height: 100%;
    background: linear-gradient(90deg, var(--course-primary) 0%, var(--course-primary-light) 100%);
    border-radius: 4px;
    transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.course-player-page .progress-bar-inner::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    animation: course-progress-shine 2s ease-in-out infinite;
}

/* ---------- 课时内容 ---------- */
.course-player-page .player-lesson-content {
    font-size: 14px;
    line-height: 1.8;
    color: var(--course-text-muted);
    margin-bottom: 16px;
    padding: 14px 18px;
    background: var(--course-bg);
    border-radius: var(--course-radius);
    border-left: 3px solid var(--course-primary-light);
}

/* ---------- 附件区 ---------- */
.course-player-page .player-attachments {
    margin-bottom: 16px;
    padding: 16px 18px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
}

.course-player-page .attachments-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--course-text);
    margin-bottom: 12px;
}

.course-player-page .attachments-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.course-player-page .attachment-link {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 14px;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    text-decoration: none;
    color: var(--course-text);
    transition: var(--course-transition);
}

.course-player-page .attachment-link:hover {
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
    transform: translateX(2px);
}

.course-player-page .attachment-icon {
    font-size: 18px;
    flex-shrink: 0;
}

.course-player-page .attachment-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 2px;
    min-width: 0;
}

.course-player-page .attachment-title {
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text);
}

.course-player-page .attachment-meta {
    font-size: 11px;
    color: var(--course-text-light);
}

.course-player-page .attachment-dl {
    font-size: 12px;
    color: var(--course-primary);
    flex-shrink: 0;
}

/* ---------- 导航按钮 ---------- */
.course-player-page .player-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 24px;
    padding: 16px 0;
    border-top: 1px solid var(--course-border);
}

.course-player-page .nav-buttons {
    display: flex;
    gap: 10px;
}

.course-player-page .nav-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 9px 18px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text);
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    text-decoration: none;
    transition: var(--course-transition);
}

.course-player-page .nav-btn:hover:not(.disabled) {
    color: var(--course-primary);
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
    transform: translateY(-1px);
}

.course-player-page .nav-btn.disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.course-player-page .player-complete-btn {
    padding: 10px 22px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, var(--course-primary) 0%, var(--course-primary-dark) 100%);
    border: none;
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
}

.course-player-page .player-complete-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.3);
}

.course-player-page .player-complete-btn.completed {
    background: #16a34a;
    box-shadow: 0 2px 8px rgba(22, 163, 74, 0.2);
}

/* ========================================================================
   课时评论模块样式
   ======================================================================== */

.course-player-page .lesson-comments-section {
    margin-top: 20px;
    padding: 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

.course-player-page .comments-header {
    margin-bottom: 18px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--course-border);
}

.course-player-page .comments-title {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 0;
    font-size: 17px;
    font-weight: 700;
    color: var(--course-text);
}

.course-player-page .comments-icon {
    font-size: 20px;
}

.course-player-page .comments-count {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 24px;
    height: 22px;
    padding: 0 8px;
    font-size: 12px;
    font-weight: 600;
    color: #fff;
    background: var(--course-primary);
    border-radius: 11px;
}

/* ---------- Flash 提示 ---------- */
.course-player-page .comment-flash {
    padding: 10px 14px;
    margin-bottom: 14px;
    border-radius: var(--course-radius-sm);
    font-size: 13px;
}

.course-player-page .comment-flash-success {
    color: #15803d;
    background: #dcfce7;
    border: 1px solid #bbf7d0;
}

.course-player-page .comment-flash-error {
    color: #b91c1c;
    background: #fee2e2;
    border: 1px solid #fecaca;
}

/* ---------- 评论输入框 ---------- */
.course-player-page .comment-form-wrap {
    margin-bottom: 20px;
}

.course-player-page .comment-form {
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    padding: 14px;
    transition: var(--course-transition);
}

.course-player-page .comment-form:focus-within {
    border-color: var(--course-primary-light);
    box-shadow: 0 0 0 3px var(--course-primary-bg);
}

.course-player-page .comment-textarea-wrap {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.course-player-page .comment-textarea {
    width: 100%;
    min-height: 72px;
    padding: 10px 12px;
    font-size: 14px;
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    resize: vertical;
    transition: var(--course-transition);
}

.course-player-page .comment-textarea:focus {
    outline: none;
    border-color: var(--course-primary);
}

.course-player-page .comment-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}

.course-player-page .comment-hint {
    font-size: 12px;
    color: var(--course-text-light);
}

.course-player-page .comment-submit-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 7px 18px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, var(--course-primary) 0%, var(--course-primary-dark) 100%);
    border: none;
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
}

.course-player-page .comment-submit-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 3px 10px rgba(99, 102, 241, 0.3);
}

.course-player-page .comment-submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* ---------- 登录提示 ---------- */
.course-player-page .comment-login-hint {
    padding: 14px 18px;
    margin-bottom: 18px;
    text-align: center;
    font-size: 13px;
    color: var(--course-text-muted);
    background: var(--course-bg);
    border: 1px dashed var(--course-border);
    border-radius: var(--course-radius);
}

.course-player-page .comment-login-hint a {
    color: var(--course-primary);
    font-weight: 600;
    text-decoration: none;
}

.course-player-page .comment-login-hint a:hover {
    text-decoration: underline;
}

/* ---------- 评论列表 ---------- */
.course-player-page .comments-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.course-player-page .comments-empty {
    padding: 36px 20px;
    text-align: center;
    color: var(--course-text-light);
}

.course-player-page .comments-empty .empty-icon {
    font-size: 40px;
    margin-bottom: 8px;
    opacity: 0.4;
}

.course-player-page .comments-empty p {
    margin: 0;
    font-size: 13px;
}

/* 单条评论 */
.course-player-page .comment-item {
    display: flex;
    gap: 12px;
}

.course-player-page .comment-avatar {
    flex-shrink: 0;
    width: 38px;
    height: 38px;
    border-radius: 50%;
    overflow: hidden;
    background: var(--course-primary-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--course-primary);
    font-weight: 600;
    font-size: 14px;
}

.course-player-page .comment-avatar.avatar-sm {
    width: 30px;
    height: 30px;
    font-size: 12px;
}

.course-player-page .comment-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.course-player-page .avatar-text {
    line-height: 1;
}

.course-player-page .comment-body {
    flex: 1;
    min-width: 0;
}

.course-player-page .comment-meta {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 4px;
}

.course-player-page .comment-author {
    font-size: 13px;
    font-weight: 600;
    color: var(--course-text);
}

.course-player-page .comment-time {
    font-size: 12px;
    color: var(--course-text-light);
}

.course-player-page .comment-content {
    font-size: 14px;
    line-height: 1.6;
    color: var(--course-text);
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.course-player-page .comment-actions {
    display: flex;
    gap: 14px;
    margin-top: 6px;
}

.course-player-page .comment-reply-btn,
.course-player-page .comment-delete-btn {
    font-size: 12px;
    color: var(--course-text-light);
    text-decoration: none;
    transition: var(--course-transition);
    cursor: pointer;
}

.course-player-page .comment-reply-btn:hover {
    color: var(--course-primary);
}

.course-player-page .comment-delete-btn:hover {
    color: #dc2626;
}

/* 回复列表 */
.course-player-page .comment-replies {
    margin-top: 12px;
    padding: 12px 14px;
    background: var(--course-bg);
    border-radius: var(--course-radius-sm);
    border-left: 2px solid var(--course-border);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.course-player-page .comment-item.reply {
    gap: 10px;
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
    .course-player-page .live-badge {
        top: 8px;
        left: 8px;
        font-size: 11px;
        padding: 3px 8px;
    }

    .course-player-page .video-type-badge {
        display: block;
        margin: 6px 0 0;
        width: fit-content;
    }

    .course-player-page .lesson-title {
        font-size: 17px;
    }

    .course-player-page .player-nav {
        flex-direction: column;
        align-items: stretch;
    }

    .course-player-page .nav-buttons {
        flex-direction: column;
    }

    .course-player-page .nav-btn,
    .course-player-page .player-complete-btn {
        width: 100%;
        justify-content: center;
    }

    .course-player-page .player-nav-right {
        flex-direction: column;
        gap: 8px;
        width: 100%;
    }

    .course-player-page .free-view-badge {
        width: 100%;
        justify-content: center;
    }

    .course-player-page .lesson-comments-section {
        padding: 16px;
    }

    .course-player-page .comment-toolbar {
        flex-direction: column;
        align-items: stretch;
        gap: 8px;
    }

    .course-player-page .comment-submit-btn {
        width: 100%;
        justify-content: center;
    }
}

/* ==================== 详情页通用区块标题 ==================== */

.section-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0 0 18px;
    padding-left: 12px;
    border-left: 4px solid var(--course-primary);
    line-height: 1.3;
}

/* ==================== 课程附件区（详情页） ==================== */

.course-attachments-section {
    margin-top: 36px;
    padding: 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

.attachment-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.attachment-item {
    margin: 0;
    padding: 0;
}

.attachment-link {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 16px;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    text-decoration: none;
    color: var(--course-text);
    transition: var(--course-transition);
}

.attachment-link:hover {
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
    transform: translateX(2px);
}

.attachment-icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    background: #fff;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
}

.attachment-info {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.attachment-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--course-text);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.attachment-meta {
    font-size: 12px;
    color: var(--course-text-light);
}

/* ==================== 课时附件（播放页内联） ==================== */

.player-attachments {
    margin-top: 18px;
    padding: 14px 16px;
    background: #f8fafc;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.player-attachments .player-attachments-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--course-text);
    margin: 0 0 10px;
}

.player-attachments ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.player-attachments li {
    margin: 0;
    padding: 0;
}

.player-attachments .attachment-link {
    padding: 8px 12px;
    background: #fff;
}

.player-attachments .attachment-icon {
    width: 32px;
    height: 32px;
    font-size: 18px;
}

.player-attachments .attachment-title {
    font-size: 13px;
    font-weight: 500;
}

.player-attachments .attachment-meta {
    font-size: 11px;
}

/* ==================== 课程评价区 ==================== */

.course-reviews-section {
    margin-top: 36px;
    padding: 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

/* 评分总览 */
.reviews-summary {
    display: flex;
    gap: 32px;
    padding: 20px;
    margin-bottom: 24px;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.reviews-avg-box {
    flex: 0 0 180px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding-right: 24px;
    border-right: 1px solid var(--course-border);
}

.reviews-avg-num {
    font-size: 42px;
    font-weight: 700;
    color: var(--course-primary);
    line-height: 1;
}

.stars-readonly {
    display: inline-flex;
    gap: 2px;
    color: #d1d5db;
    font-size: 16px;
    line-height: 1;
}

.stars-readonly .star {
    color: #d1d5db;
}

.stars-readonly .star.filled {
    color: #f59e0b;
}

.reviews-count {
    font-size: 13px;
    color: var(--course-text-muted);
}

.reviews-distribution {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 6px;
    min-width: 0;
}

.dist-row {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 12px;
    color: var(--course-text-muted);
}

.dist-label {
    flex: 0 0 36px;
    text-align: right;
}

.dist-bar {
    flex: 1;
    height: 8px;
    background: #fff;
    border: 1px solid var(--course-border);
    border-radius: 4px;
    overflow: hidden;
}

.dist-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, #f59e0b 0%, #fbbf24 100%);
    border-radius: 4px;
    transition: width 0.4s ease;
}

.dist-count {
    flex: 0 0 28px;
    text-align: right;
    font-weight: 600;
    color: var(--course-text);
}

/* 评价提交表单 */
.review-form-wrap {
    padding: 20px;
    margin-bottom: 24px;
    background: #fff;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.review-form-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text);
    margin: 0 0 14px;
}

.review-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.rating-input-wrap {
    display: flex;
    align-items: center;
    gap: 10px;
}

.rating-label {
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
}

.rating-stars-input {
    display: inline-flex;
    gap: 4px;
}

.star-input {
    font-size: 22px;
    color: #d1d5db;
    cursor: pointer;
    line-height: 1;
    transition: color 0.15s ease, transform 0.15s ease;
    user-select: none;
}

.star-input:hover {
    transform: scale(1.15);
}

.star-input.active {
    color: #f59e0b;
}

.rating-display-text {
    font-size: 13px;
    font-weight: 600;
    color: #f59e0b;
}

.review-content-wrap textarea {
    width: 100%;
    padding: 10px 12px;
    font-size: 14px;
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    outline: none;
    resize: vertical;
    min-height: 80px;
    transition: var(--course-transition);
    box-sizing: border-box;
}

.review-content-wrap textarea:focus {
    border-color: var(--course-primary);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

.review-actions {
    display: flex;
    justify-content: flex-end;
}

.review-actions .btn-primary {
    height: 38px;
    padding: 0 22px;
    font-size: 13px;
    font-weight: 600;
    color: #fff;
    background: var(--course-primary);
    border: 1px solid var(--course-primary);
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.review-actions .btn-primary:hover {
    background: var(--course-primary-dark);
    border-color: var(--course-primary-dark);
}

/* 登录提示 */
.review-login-hint {
    padding: 16px 20px;
    margin-bottom: 24px;
    background: var(--course-primary-bg);
    border: 1px dashed var(--course-primary-light);
    border-radius: var(--course-radius);
    font-size: 13px;
    color: var(--course-text-muted);
    text-align: center;
}

.review-login-hint a {
    color: var(--course-primary);
    font-weight: 600;
    text-decoration: none;
}

.review-login-hint a:hover {
    text-decoration: underline;
}

/* 评价列表 */
.reviews-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

/* 课时评论（详情页公开展示） */
.reviews-section-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 16px;
}

.reviews-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0;
}

.lesson-comments-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.lesson-comment-item {
    padding: 14px 16px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
}

.lesson-comment-header {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 6px;
}

.lesson-comment-lesson {
    padding: 2px 8px;
    font-size: 12px;
    background: var(--course-primary-bg);
    color: var(--course-primary);
    border-radius: 10px;
    font-weight: 500;
}

.lesson-comment-content {
    font-size: 14px;
    line-height: 1.6;
    color: var(--course-text);
    white-space: pre-wrap;
    word-break: break-word;
}

.reviews-empty {
    padding: 40px 20px;
    text-align: center;
    color: var(--course-text-light);
    font-size: 14px;
    background: var(--course-bg);
    border: 1px dashed var(--course-border);
    border-radius: var(--course-radius);
}

.review-item {
    padding: 16px 18px;
    background: #fff;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    transition: var(--course-transition);
}

.review-item:hover {
    border-color: var(--course-primary-light);
    box-shadow: var(--course-shadow);
}

.review-item-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 8px;
    flex-wrap: wrap;
}

.review-author {
    font-size: 14px;
    font-weight: 600;
    color: var(--course-text);
}

.review-time {
    font-size: 12px;
    color: var(--course-text-light);
    margin-left: auto;
}

.review-content {
    font-size: 14px;
    line-height: 1.7;
    color: var(--course-text-muted);
    word-break: break-word;
    white-space: pre-wrap;
}

/* ==================== 楼中楼 + 管理员操作样式 ==================== */

/* 内联回复框 */
.comment-inline-reply,
.comment-inline-edit,
.review-inline-edit {
    margin-top: 8px;
    padding: 10px;
    background: var(--course-bg, #f8fafc);
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: var(--course-radius-sm, 8px);
}

.inline-reply-textarea,
.inline-edit-textarea {
    width: 100%;
    min-height: 50px;
    padding: 8px 10px;
    font-size: 13px;
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: 6px;
    resize: vertical;
    box-sizing: border-box;
    margin-bottom: 8px;
    font-family: inherit;
}

.inline-reply-textarea:focus,
.inline-edit-textarea:focus {
    outline: none;
    border-color: var(--course-primary, #6366f1);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.1);
}

.inline-reply-actions,
.inline-edit-actions {
    display: flex;
    gap: 8px;
}

.btn-cancel-sm {
    padding: 5px 14px;
    font-size: 13px;
    color: var(--course-text-muted, #64748b);
    background: transparent;
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: var(--course-radius-sm, 6px);
    cursor: pointer;
    transition: all 0.2s;
}

.btn-cancel-sm:hover {
    background: var(--course-bg, #f1f5f9);
}

/* 评论操作按钮 */
.comment-actions {
    display: flex;
    gap: 12px;
    margin-top: 4px;
}

.comment-actions a,
.review-actions-bar a {
    font-size: 12px;
    color: var(--course-text-light, #94a3b8);
    text-decoration: none;
    transition: color 0.2s;
}

.comment-actions a:hover,
.review-actions-bar a:hover {
    color: var(--course-primary, #6366f1);
}

.comment-edit-btn:hover,
.review-edit-btn:hover {
    color: var(--course-primary, #6366f1);
}

.comment-delete-btn:hover,
.review-delete-btn:hover {
    color: #dc2626;
}

/* 评价操作栏 */
.review-actions-bar {
    display: flex;
    gap: 12px;
    margin-top: 8px;
    padding-top: 6px;
}

/* 楼中楼回复容器 */
.comment-replies {
    margin-top: 10px;
    padding-left: 12px;
    border-left: 2px solid var(--course-border, #e2e8f0);
}

.comment-item.reply {
    margin-bottom: 8px;
    padding: 8px 10px;
    background: var(--course-bg, #f8fafc);
    border-radius: var(--course-radius-sm, 8px);
}

.comment-item.reply .comment-meta {
    gap: 6px;
}

.comment-item.reply .comment-author {
    font-size: 13px;
}

.comment-item.reply .comment-content {
    font-size: 13px;
    margin-top: 2px;
}

/* ==================== 课程详情页评价筛选标签 ==================== */

/* 追评表单 */
.review-followup-wrap {
    margin-bottom: 20px;
    padding: 16px 18px;
    background: linear-gradient(135deg, #f0f4ff 0%, #f7f8fa 100%);
    border: 1px solid #c7d2fe;
    border-radius: var(--course-radius);
}

.review-followup-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
}

.followup-icon {
    font-size: 18px;
    color: var(--course-primary);
}

.followup-title {
    font-size: 14px;
    font-weight: 700;
    color: var(--course-text);
}

.followup-hint {
    font-size: 12px;
    color: var(--course-text-light);
    margin-left: auto;
}

.review-followup-form textarea {
    width: 100%;
    min-height: 60px;
    padding: 10px 12px;
    font-size: 14px;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    resize: vertical;
    box-sizing: border-box;
    margin-bottom: 10px;
}

.review-followup-form textarea:focus {
    outline: none;
    border-color: var(--course-primary);
    box-shadow: 0 0 0 3px var(--course-primary-bg);
}

.btn-sm {
    padding: 5px 16px;
    font-size: 13px;
}

/* 已有追评展示 */
.review-followup-existing {
    padding: 10px 12px;
    background: #fff;
    border-radius: var(--course-radius-sm);
    border: 1px solid var(--course-border);
}

.followup-existing-content {
    font-size: 14px;
    line-height: 1.6;
    color: var(--course-text);
    white-space: pre-wrap;
    word-break: break-word;
}

.followup-existing-time {
    font-size: 12px;
    color: var(--course-text-light);
    margin-top: 6px;
}

/* 评价列表中追评展示 */
.review-followup-display {
    margin-top: 10px;
    padding: 10px 12px;
    background: #f8fafc;
    border-left: 3px solid var(--course-primary, #6366f1);
    border-radius: 0 6px 6px 0;
}

.followup-label {
    margin-bottom: 4px;
}

.followup-tag {
    display: inline-flex;
    align-items: center;
    padding: 1px 8px;
    font-size: 11px;
    font-weight: 600;
    color: #fff;
    background: var(--course-primary, #6366f1);
    border-radius: 4px;
}

.followup-text {
    font-size: 13px;
    line-height: 1.6;
    color: var(--course-text-muted);
    white-space: pre-wrap;
    word-break: break-word;
}

.followup-time {
    font-size: 11px;
    color: var(--course-text-light);
    margin-top: 4px;
}

/* ==================== 课程详情页评价筛选标签 ==================== */

.review-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 18px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--course-border);
}

.review-filter-item {
    display: inline-flex;
    align-items: center;
    padding: 5px 14px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
    background: var(--course-bg);
    border: 1px solid transparent;
    border-radius: 20px;
    cursor: pointer;
    user-select: none;
    transition: all 0.2s ease;
}

.review-filter-item:hover {
    color: var(--course-primary);
    background: rgba(99, 102, 241, 0.08);
}

.review-filter-item.active {
    color: #fff;
    background: var(--course-primary);
    border-color: var(--course-primary);
}

/* 评价项评分等级标签 */
.review-rating-tag {
    display: inline-flex;
    align-items: center;
    padding: 1px 8px;
    font-size: 11px;
    font-weight: 600;
    border-radius: 4px;
    line-height: 1.5;
}

.review-rating-tag.tag-good {
    color: #16a34a;
    background: #dcfce7;
}

.review-rating-tag.tag-medium {
    color: #2563eb;
    background: #dbeafe;
}

.review-rating-tag.tag-normal {
    color: #ca8a04;
    background: #fef9c3;
}

.review-rating-tag.tag-bad {
    color: #dc2626;
    background: #fee2e2;
}

/* ==================== 评价/附件区响应式 ==================== */

@media (max-width: 768px) {
    .reviews-summary {
        flex-direction: column;
        gap: 18px;
        padding: 16px;
    }

    .reviews-avg-box {
        flex: 0 0 auto;
        padding-right: 0;
        padding-bottom: 16px;
        border-right: none;
        border-bottom: 1px solid var(--course-border);
    }

    .reviews-avg-num {
        font-size: 36px;
    }

    .course-attachments-section,
    .course-reviews-section {
        padding: 16px;
    }

    .attachment-link {
        padding: 12px;
    }

    .attachment-icon {
        width: 36px;
        height: 36px;
        font-size: 20px;
    }

    .review-item {
        padding: 14px;
    }

    .review-time {
        margin-left: 0;
        width: 100%;
    }
}

/* ========================================================================
   课程详情页 - 精美样式（v2）
   匹配 detail.php 模板中的实际 class 命名
   ======================================================================== */

/* ---------- 返回链接 ---------- */

.course-detail-page .back-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
    text-decoration: none;
    padding: 6px 14px 6px 10px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: 20px;
    transition: var(--course-transition);
}

.course-detail-page .back-link:hover {
    color: var(--course-primary);
    border-color: var(--course-primary-light);
    background: var(--course-primary-bg);
    transform: translateX(-2px);
}

/* ---------- 课程头部卡片（封面 + 信息） ---------- */

.course-detail-page .course-detail {
    display: flex;
    gap: 28px;
    align-items: flex-start;
    margin-bottom: 28px;
    padding: 28px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow-lg);
    position: relative;
    overflow: hidden;
}

/* 顶部装饰渐变条 */
.course-detail-page .course-detail::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--course-primary) 0%, var(--course-primary-light) 50%, #a78bfa 100%);
}

/* ---------- 封面 ---------- */

.course-detail-page .course-detail-cover {
    flex: 0 0 340px;
    width: 340px;
    height: 210px;
    border-radius: var(--course-radius);
    overflow: hidden;
    background: linear-gradient(135deg, #eef2ff 0%, #e0e7ff 50%, #ddd6fe 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.1);
}

.course-detail-page .course-detail-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}

.course-detail-page .course-detail-cover:hover img {
    transform: scale(1.03);
}

.course-detail-page .course-cover-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
}

.course-detail-page .cover-icon {
    font-size: 64px;
    opacity: 0.5;
}

/* ---------- 信息区 ---------- */

.course-detail-page .course-detail-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 14px;
    min-width: 0;
}

.course-detail-page .course-detail-title {
    font-size: 26px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0;
    line-height: 1.35;
    letter-spacing: -0.01em;
}

/* ---------- Meta 行（课时数 / 分类 / 评分） ---------- */

.course-detail-page .course-detail-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
    font-size: 13px;
    color: var(--course-text-muted);
}

.course-detail-page .lesson-count,
.course-detail-page .course-cat {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 12px;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: 16px;
    font-weight: 500;
    color: var(--course-text-muted);
}

.course-detail-page .course-rating-summary {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.course-detail-page .rating-text {
    font-size: 13px;
    font-weight: 600;
    color: #f59e0b;
}

/* ---------- 描述 ---------- */

.course-detail-page .course-detail-desc {
    font-size: 14px;
    color: var(--course-text-muted);
    line-height: 1.7;
    margin: 0;
    padding: 12px 16px;
    background: var(--course-bg);
    border-radius: var(--course-radius-sm);
    border-left: 3px solid var(--course-primary-light);
}

/* ---------- 价格区 ---------- */

.course-detail-page .course-price-box {
    display: flex;
    align-items: baseline;
    gap: 10px;
    padding: 12px 0;
}

.course-detail-page .price-normal {
    font-size: 28px;
    font-weight: 700;
    color: var(--course-primary);
    letter-spacing: -0.02em;
}

.course-detail-page .price-discount {
    font-size: 28px;
    font-weight: 700;
    color: #dc2626;
    letter-spacing: -0.02em;
}

.course-detail-page .price-original {
    font-size: 15px;
    color: var(--course-text-light);
}

.course-detail-page .price-free {
    font-size: 28px;
    font-weight: 700;
    color: #16a34a;
    letter-spacing: -0.02em;
}

/* ---------- 已购买徽章 ---------- */

.course-detail-page .course-owned-badge {
    margin-top: 4px;
}

.course-detail-page .perm-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 6px 16px;
    font-size: 13px;
    font-weight: 600;
    border-radius: 20px;
}

.course-detail-page .perm-badge.perm-allowed {
    color: #15803d;
    background: #dcfce7;
    border: 1px solid #bbf7d0;
}

.course-detail-page .free-view-quota {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    font-size: 12px;
    font-weight: 600;
    color: #c2410c;
    background: #fff7ed;
    border: 1px solid #fed7aa;
    border-radius: 14px;
    margin-left: 4px;
}

/* ---------- 按钮 ---------- */

.course-detail-page .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    height: 44px;
    padding: 0 28px;
    font-size: 14px;
    font-weight: 600;
    font-family: var(--course-font);
    border-radius: var(--course-radius-sm);
    text-decoration: none;
    cursor: pointer;
    transition: var(--course-transition);
    border: 1px solid transparent;
    white-space: nowrap;
}

.course-detail-page .btn-primary {
    background: linear-gradient(135deg, var(--course-primary) 0%, var(--course-primary-dark) 100%);
    color: #fff;
    border-color: var(--course-primary);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.25);
}

.course-detail-page .btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.35);
}

.course-detail-page .btn-primary:active {
    transform: translateY(0);
}

.course-detail-page .btn-outline {
    background: transparent;
    color: var(--course-primary);
    border-color: var(--course-primary-light);
}

.course-detail-page .btn-outline:hover {
    background: var(--course-primary-bg);
    border-color: var(--course-primary);
}

.course-detail-page .btn-sm {
    height: 32px;
    padding: 0 16px;
    font-size: 12px;
    border-radius: 6px;
}

/* ---------- 访问拒绝提示 ---------- */

.course-detail-page .access-denied-box {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px 24px;
    margin-bottom: 28px;
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: var(--course-radius-lg);
}

.course-detail-page .access-denied-icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    background: #fee2e2;
    border-radius: 50%;
}

.course-detail-page .access-denied-text h3 {
    margin: 0 0 4px;
    font-size: 15px;
    font-weight: 600;
    color: #991b1b;
}

.course-detail-page .access-denied-text p {
    margin: 0;
    font-size: 13px;
    color: #b91c1c;
}

/* ---------- 学习进度条 ---------- */

.course-detail-page .course-progress-section {
    margin-bottom: 28px;
    padding: 20px 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

.course-detail-page .progress-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted);
}

.course-detail-page .progress-text {
    font-size: 14px;
    font-weight: 700;
    color: var(--course-primary);
}

.course-detail-page .progress-bar {
    width: 100%;
    height: 10px;
    background: var(--course-bg);
    border-radius: 5px;
    overflow: hidden;
    position: relative;
}

.course-detail-page .progress-bar-inner {
    height: 100%;
    background: linear-gradient(90deg, var(--course-primary) 0%, var(--course-primary-light) 100%);
    border-radius: 5px;
    transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

/* 进度条动画光泽 */
.course-detail-page .progress-bar-inner::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%);
    animation: course-progress-shine 2s ease-in-out infinite;
}

@keyframes course-progress-shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

/* ---------- 课时列表区 ---------- */

.course-detail-page .lesson-list-section {
    margin-bottom: 28px;
}

.course-detail-page .lesson-list {
    list-style: none;
    margin: 0;
    padding: 0;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
    overflow: hidden;
}

.course-detail-page .lesson-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 16px 20px;
    border-bottom: 1px solid var(--course-border);
    transition: var(--course-transition);
}

.course-detail-page .lesson-item:last-child {
    border-bottom: none;
}

.course-detail-page .lesson-item:hover {
    background: var(--course-primary-bg);
}

.course-detail-page .lesson-item-num {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
    color: var(--course-text-muted);
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: 50%;
    transition: var(--course-transition);
}

.course-detail-page .lesson-item:hover .lesson-item-num {
    background: var(--course-primary);
    color: #fff;
    border-color: var(--course-primary);
}

.course-detail-page .lesson-item-main {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.course-detail-page .lesson-item-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--course-text);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.course-detail-page .lesson-item-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    color: var(--course-text-light);
}

.course-detail-page .lesson-duration {
    display: inline-flex;
    align-items: center;
    gap: 3px;
}

.course-detail-page .lesson-free-tag {
    display: inline-flex;
    align-items: center;
    padding: 2px 8px;
    font-size: 11px;
    font-weight: 600;
    color: #15803d;
    background: #dcfce7;
    border-radius: 10px;
}

.course-detail-page .lesson-item-action {
    flex-shrink: 0;
    display: flex;
    align-items: center;
}

.course-detail-page .lesson-status-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    font-size: 14px;
}

.course-detail-page .lesson-status-icon.done {
    color: #16a34a;
    font-weight: 700;
}

.course-detail-page .lesson-status-icon.locked {
    color: var(--course-text-light);
    opacity: 0.6;
}

/* 已完成课时 */
.course-detail-page .lesson-item.completed .lesson-item-num {
    background: #dcfce7;
    color: #15803d;
    border-color: #bbf7d0;
}

.course-detail-page .lesson-item.completed .lesson-item-title {
    color: var(--course-text-muted);
}

/* 锁定课时 */
.course-detail-page .lesson-item.locked {
    opacity: 0.6;
}

.course-detail-page .lesson-item.locked:hover {
    background: var(--course-bg);
}

.course-detail-page .lesson-item.locked .lesson-item-num {
    background: var(--course-bg);
    color: var(--course-text-light);
}

/* ---------- 空状态 ---------- */

.course-detail-page .course-empty {
    padding: 48px 24px;
    text-align: center;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
}

.course-detail-page .course-empty .empty-icon {
    font-size: 48px;
    margin-bottom: 12px;
    opacity: 0.4;
}

.course-detail-page .course-empty p {
    margin: 0;
    font-size: 14px;
    color: var(--course-text-light);
}

/* ---------- 详情页响应式 ---------- */

@media (max-width: 900px) {
    .course-detail-page .course-detail {
        flex-direction: column;
        gap: 20px;
        padding: 20px;
    }

    .course-detail-page .course-detail-cover {
        flex: 0 0 auto;
        width: 100%;
        height: 200px;
    }

    .course-detail-page .course-detail-title {
        font-size: 22px;
    }
}

@media (max-width: 600px) {
    .course-detail-page .course-detail {
        padding: 16px;
    }

    .course-detail-page .course-detail-cover {
        height: 180px;
    }

    .course-detail-page .course-detail-title {
        font-size: 19px;
    }

    .course-detail-page .course-detail-desc {
        padding: 10px 12px;
        font-size: 13px;
    }

    .course-detail-page .price-normal,
    .course-detail-page .price-discount,
    .course-detail-page .price-free {
        font-size: 24px;
    }

    .course-detail-page .btn {
        width: 100%;
    }

    .course-detail-page .lesson-item {
        padding: 12px 14px;
        gap: 10px;
    }

    .course-detail-page .lesson-item-num {
        width: 28px;
        height: 28px;
        font-size: 12px;
    }

    .course-detail-page .lesson-item-title {
        font-size: 13px;
    }

    .course-detail-page .course-progress-section,
    .course-detail-page .access-denied-box {
        padding: 14px 16px;
    }
}

/* ==================== 章节分组样式 ==================== */

.course-detail-page .lesson-chapter-group {
    margin-bottom: 20px;
}

.course-detail-page .lesson-chapter-group:last-child {
    margin-bottom: 0;
}

.course-detail-page .lesson-chapter-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 20px;
    background: linear-gradient(135deg, #eef2ff 0%, #ede9fe 100%);
    border: 1px solid var(--course-primary-light);
    border-bottom: none;
    border-radius: var(--course-radius-lg) var(--course-radius-lg) 0 0;
}

.course-detail-page .lesson-chapter-header.no-chapter {
    background: var(--course-bg);
    border-color: var(--course-border);
}

.course-detail-page .chapter-icon {
    font-size: 18px;
}

.course-detail-page .chapter-title {
    flex: 1;
    font-size: 15px;
    font-weight: 700;
    color: var(--course-text);
}

.course-detail-page .chapter-count {
    font-size: 12px;
    font-weight: 600;
    color: var(--course-primary);
    background: #fff;
    padding: 3px 10px;
    border-radius: 12px;
    border: 1px solid var(--course-primary-light);
}

.course-detail-page .lesson-chapter-group .lesson-list {
    border-radius: 0 0 var(--course-radius-lg) var(--course-radius-lg);
    border-top: none;
}

.course-detail-page .lesson-chapter-group .lesson-list .lesson-item:first-child {
    border-top: none;
}

/* ==================== 附件提取码：锁标志与按钮 ==================== */

.attachment-item.is-locked .attachment-link.attachment-locked-trigger {
    display: flex;
    align-items: center;
    gap: 12px;
    width: 100%;
    padding: 12px 14px;
    background: linear-gradient(90deg, #fffbeb 0%, #ffffff 60%);
    border: 1px solid #fde68a;
    border-radius: 10px;
    cursor: pointer;
    text-align: left;
    font: inherit;
    color: inherit;
    transition: all 0.18s ease;
    appearance: none;
    -webkit-appearance: none;
}

.attachment-item.is-locked .attachment-link.attachment-locked-trigger:hover {
    background: linear-gradient(90deg, #fef3c7 0%, #fffbeb 60%);
    border-color: #f59e0b;
    box-shadow: 0 2px 8px rgba(245, 158, 11, 0.12);
}

.attachment-item.is-locked .attachment-icon {
    background: #fef3c7;
    color: #d97706;
    border-color: #fde68a;
}

.attachment-item.is-locked .att-lock-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    margin-right: 6px;
    background: #f59e0b;
    color: #fff;
    border-radius: 50%;
    font-size: 12px;
    vertical-align: middle;
}

.attachment-item.is-locked .attachment-title {
    color: #92400e;
    font-weight: 600;
}

.attachment-item.is-locked .att-locked-tag {
    display: inline-block;
    margin-left: 4px;
    padding: 1px 8px;
    background: #f59e0b;
    color: #fff;
    border-radius: 10px;
    font-size: 11px;
    font-weight: 500;
    line-height: 1.5;
}

/* ==================== 后台附件提取码徽章 ==================== */

.cp-att-code-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 3px 8px;
    background: #fffbeb;
    border: 1px solid #fde68a;
    border-radius: 6px;
    color: #92400e;
    font-size: 12px;
    line-height: 1.4;
    max-width: 100%;
}

.cp-att-code-badge .cp-att-code-icon {
    font-size: 12px;
    line-height: 1;
}

.cp-att-code-badge code {
    font-family: Consolas, Monaco, 'Courier New', monospace;
    font-size: 12px;
    color: #b45309;
    background: transparent;
    padding: 0;
    word-break: break-all;
    letter-spacing: 0.5px;
}

/* ==================== 附件提取码弹窗 ==================== */

.att-code-modal {
    position: fixed;
    inset: 0;
    z-index: 9999;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 16px;
}

.att-code-modal.is-open {
    display: flex;
}

.att-code-modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
}

.att-code-modal-card {
    position: relative;
    width: 100%;
    max-width: 420px;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.25);
    padding: 32px 28px 26px;
    animation: attCodeModalIn 0.22s ease-out;
}

@keyframes attCodeModalIn {
    from {
        opacity: 0;
        transform: translateY(-12px) scale(0.96);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.att-code-modal-close {
    position: absolute;
    top: 12px;
    right: 14px;
    width: 30px;
    height: 30px;
    background: transparent;
    border: none;
    color: #94a3b8;
    font-size: 22px;
    line-height: 1;
    cursor: pointer;
    border-radius: 50%;
    transition: all 0.15s ease;
}

.att-code-modal-close:hover {
    background: #f1f5f9;
    color: #475569;
}

.att-code-modal-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 12px;
    background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 26px;
    line-height: 1;
    box-shadow: 0 6px 16px rgba(245, 158, 11, 0.35);
}

.att-code-modal-title {
    text-align: center;
    margin: 0 0 6px;
    color: #1f2937;
    font-size: 19px;
    font-weight: 600;
}

.att-code-modal-desc {
    text-align: center;
    margin: 0 0 8px;
    color: #64748b;
    font-size: 13px;
    line-height: 1.5;
}

.att-code-modal-att-name {
    text-align: center;
    margin: 0 0 14px;
    padding: 6px 12px;
    background: #f8fafc;
    border-radius: 8px;
    color: #475569;
    font-size: 13px;
    word-break: break-all;
}

.att-code-modal-msg {
    display: none;
    margin: 0 0 12px;
    padding: 8px 12px;
    background: #fef2f2;
    border: 1px solid #fecaca;
    color: #b91c1c;
    border-radius: 8px;
    font-size: 13px;
    line-height: 1.5;
}

.att-code-modal-msg.is-error {
    display: block;
}

.att-code-modal-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.att-code-modal-input {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid #e2e8f0;
    border-radius: 10px;
    font-size: 15px;
    color: #1f2937;
    background: #f8fafc;
    text-align: center;
    letter-spacing: 2px;
    font-family: Consolas, Monaco, 'Courier New', monospace;
    transition: all 0.15s ease;
    box-sizing: border-box;
}

.att-code-modal-input:focus {
    outline: none;
    border-color: #f59e0b;
    background: #fff;
    box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.15);
}

.att-code-modal-input::placeholder {
    color: #cbd5e1;
    letter-spacing: 0;
    font-family: inherit;
}

.att-code-modal-submit {
    width: 100%;
    padding: 12px 16px;
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
    color: #fff;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.att-code-modal-submit:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 6px 16px rgba(245, 158, 11, 0.4);
}

.att-code-modal-submit:active:not(:disabled) {
    transform: translateY(0);
}

.att-code-modal-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* 响应式 */
@media (max-width: 480px) {
    .att-code-modal-card {
        padding: 24px 20px 20px;
    }

    .att-code-modal-title {
        font-size: 17px;
    }

    .att-code-modal-input {
        font-size: 14px;
        padding: 10px 12px;
    }
}

/* ==================== 播放器侧边栏章节分组 ==================== */

.course-player-page .sidebar-chapters {
    display: flex;
    flex-direction: column;
}

.course-player-page .sidebar-chapter-block {
    border-bottom: 1px solid var(--course-sidebar-border);
}

.course-player-page .sidebar-chapter-block:last-child {
    border-bottom: none;
}

.course-player-page .sidebar-chapter-title {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 16px;
    font-size: 13px;
    font-weight: 700;
    color: var(--course-sidebar-text);
    background: var(--course-sidebar-header);
    border-bottom: 1px solid var(--course-sidebar-border);
}

.course-player-page .sidebar-chapter-title small {
    margin-left: auto;
    font-size: 11px;
    font-weight: 600;
    color: var(--course-sidebar-text-muted);
    background: rgba(99, 102, 241, 0.15);
    padding: 2px 8px;
    border-radius: 10px;
}

.course-player-page .sidebar-chapter-block .sidebar-lesson-list {
    background: transparent;
    box-shadow: none;
    border: none;
    border-radius: 0;
}

.course-player-page .sidebar-chapter-block .sidebar-lesson-item {
    border-left: none;
    border-right: none;
}

.course-player-page .sidebar-chapter-block .sidebar-lesson-item .sidebar-lesson-index {
    background: var(--course-sidebar);
    color: var(--course-sidebar-text-muted);
}

.course-player-page .sidebar-chapter-block .sidebar-lesson-item:hover .sidebar-lesson-index {
    background: var(--course-primary);
}

/* 后台章节样式 */
.course-admin .chapter-form-section {
    margin-bottom: 24px;
}

.course-admin .chapter-list-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 18px;
    background: #fff;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    margin-bottom: 10px;
    transition: var(--course-transition);
}

.course-admin .chapter-list-item:hover {
    border-color: var(--course-primary-light);
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.course-admin .chapter-list-icon {
    flex-shrink: 0;
    width: 36px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    background: var(--course-primary-bg);
    border-radius: 8px;
}

.course-admin .chapter-list-info {
    flex: 1;
    min-width: 0;
}

.course-admin .chapter-list-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--course-text);
    margin-bottom: 2px;
}

.course-admin .chapter-list-meta {
    font-size: 12px;
    color: var(--course-text-light);
}

.course-admin .chapter-list-actions {
    flex-shrink: 0;
    display: flex;
    gap: 8px;
}

/* ==================== 课程介绍区 ==================== */

.course-detail-page .course-introduction-section {
    margin-bottom: 28px;
    padding: 24px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow);
}

.course-detail-page .course-introduction-content {
    font-size: 14px;
    line-height: 1.8;
    color: var(--course-text-muted);
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.course-detail-page .course-introduction-content img {
    max-width: 100%;
    height: auto;
    border-radius: var(--course-radius-sm);
    margin: 10px 0;
}

.course-detail-page .course-introduction-content h1,
.course-detail-page .course-introduction-content h2,
.course-detail-page .course-introduction-content h3,
.course-detail-page .course-introduction-content h4 {
    color: var(--course-text);
    margin: 16px 0 8px;
    line-height: 1.4;
}

.course-detail-page .course-introduction-content p {
    margin: 8px 0;
}

.course-detail-page .course-introduction-content ul,
.course-detail-page .course-introduction-content ol {
    padding-left: 20px;
    margin: 8px 0;
}

.course-detail-page .course-introduction-content li {
    margin: 4px 0;
}

.course-detail-page .course-introduction-content a {
    color: var(--course-primary);
    text-decoration: none;
}

.course-detail-page .course-introduction-content a:hover {
    text-decoration: underline;
}

.course-detail-page .course-introduction-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 10px 0;
}

.course-detail-page .course-introduction-content th,
.course-detail-page .course-introduction-content td {
    border: 1px solid var(--course-border);
    padding: 8px 12px;
    text-align: left;
}

.course-detail-page .course-introduction-content th {
    background: var(--course-bg);
    font-weight: 600;
}

.course-detail-page .course-introduction-content blockquote {
    margin: 12px 0;
    padding: 10px 16px;
    border-left: 4px solid var(--course-primary-light);
    background: var(--course-bg);
    color: var(--course-text-muted);
}

.course-detail-page .course-introduction-content pre {
    margin: 10px 0;
    padding: 12px 16px;
    background: #1e293b;
    color: #e2e8f0;
    border-radius: var(--course-radius-sm);
    overflow-x: auto;
    font-size: 13px;
    line-height: 1.6;
}

.course-detail-page .course-introduction-content code {
    background: var(--course-bg);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
    color: var(--course-primary-dark);
}

.course-detail-page .course-introduction-content pre code {
    background: transparent;
    padding: 0;
    color: inherit;
}

/* ==================== 密码输入界面 ==================== */

.password-prompt-section {
    display: flex;
    justify-content: center;
    padding: 40px 20px;
}

.password-prompt-card {
    max-width: 440px;
    width: 100%;
    padding: 36px 32px;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-lg);
    box-shadow: var(--course-shadow-lg);
    text-align: center;
}

.password-prompt-icon {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.8;
}

.password-prompt-title {
    font-size: 22px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0 0 8px;
}

.password-prompt-desc {
    font-size: 14px;
    color: var(--course-text-muted);
    margin: 0 0 24px;
    line-height: 1.6;
}

.password-prompt-error {
    padding: 10px 16px;
    margin-bottom: 16px;
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: var(--course-radius-sm);
    font-size: 13px;
    color: #dc2626;
    text-align: center;
}

.password-prompt-input-wrap {
    display: flex;
    gap: 10px;
    align-items: stretch;
}

.password-prompt-input-wrap input[type="password"] {
    flex: 1;
    min-width: 0;
    height: 44px;
    padding: 0 16px;
    font-size: 15px;
    font-family: var(--course-font);
    color: var(--course-text);
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    outline: none;
    transition: var(--course-transition);
    box-sizing: border-box;
}

.password-prompt-input-wrap input[type="password"]:focus {
    border-color: var(--course-primary);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

.password-prompt-input-wrap .btn-primary {
    flex-shrink: 0;
    height: 44px;
    padding: 0 24px;
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, var(--course-primary) 0%, var(--course-primary-dark) 100%);
    border: 1px solid var(--course-primary);
    border-radius: var(--course-radius-sm);
    cursor: pointer;
    transition: var(--course-transition);
    white-space: nowrap;
}

.password-prompt-input-wrap .btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.password-prompt-back {
    margin-top: 20px;
    font-size: 13px;
}

.password-prompt-back a {
    color: var(--course-text-muted);
    text-decoration: none;
    transition: var(--course-transition);
}

.password-prompt-back a:hover {
    color: var(--course-primary);
}

/* 播放器页面密码样式 */
.course-player-page .password-prompt-section {
    padding: 60px 20px;
}

/* ==================== 课程详情 Tab 切换 ==================== */

.course-detail-page .course-tabs {
    margin-bottom: 28px;
}

.course-detail-page .tabs-nav {
    display: flex;
    gap: 0;
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-bottom: none;
    border-radius: var(--course-radius-lg) var(--course-radius-lg) 0 0;
    overflow: hidden;
}

.course-detail-page .tab-item {
    flex: 1;
    padding: 16px 20px;
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text-muted);
    text-align: center;
    cursor: pointer;
    border-bottom: 3px solid transparent;
    transition: var(--course-transition);
    user-select: none;
}

.course-detail-page .tab-item:hover {
    color: var(--course-primary);
    background: var(--course-primary-bg);
}

.course-detail-page .tab-item.active {
    color: var(--course-primary);
    border-bottom-color: var(--course-primary);
    background: var(--course-primary-bg);
}

.course-detail-page .tab-count {
    display: inline-block;
    margin-left: 6px;
    padding: 1px 8px;
    font-size: 12px;
    font-weight: 500;
    color: var(--course-text-muted);
    background: var(--course-bg);
    border-radius: 10px;
    transition: var(--course-transition);
}

.course-detail-page .tab-item.active .tab-count {
    color: var(--course-primary);
    background: #fff;
}

.course-detail-page .tabs-content {
    background: var(--course-card-bg);
    border: 1px solid var(--course-border);
    border-radius: 0 0 var(--course-radius-lg) var(--course-radius-lg);
    box-shadow: var(--course-shadow);
    overflow: hidden;
}

.course-detail-page .tab-pane {
    display: none;
    padding: 24px;
}

.course-detail-page .tab-pane.active {
    display: block;
}

/* Tab 内的 section 调整 */
.course-detail-page .tab-pane .lesson-list-section {
    margin-bottom: 0;
    padding: 0;
    background: transparent;
    border: none;
    box-shadow: none;
}

.course-detail-page .tab-pane .section-title,
.course-detail-page .tab-pane .subsection-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--course-text);
    margin: 0 0 16px;
    padding: 0;
    border-left: 4px solid var(--course-primary);
    padding-left: 12px;
}

.course-detail-page .tab-pane .course-introduction-content {
    padding: 0;
}

.course-detail-page .tab-pane .course-attachments-section {
    margin-bottom: 0;
    margin-top: 24px;
    padding: 20px 0 0;
    border-top: 1px solid var(--course-border);
    background: transparent;
    border-left: none;
    border-right: none;
    border-bottom: none;
    border-radius: 0;
    box-shadow: none;
}

.course-detail-page .tab-pane .course-reviews-section {
    padding: 0;
    background: transparent;
    border: none;
    box-shadow: none;
}

/* ==================== 附件 Tab 样式 ==================== */

.course-detail-page .attachments-group {
    margin-bottom: 20px;
}

.course-detail-page .attachments-group:last-child {
    margin-bottom: 0;
}

.course-detail-page .attachments-divider {
    height: 1px;
    background: var(--course-border);
    margin: 24px 0;
}

.course-detail-page .lesson-attachment-group {
    margin-bottom: 18px;
    padding: 16px;
    background: var(--course-bg);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.course-detail-page .lesson-attachment-group:last-child {
    margin-bottom: 0;
}

.course-detail-page .lesson-attachment-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--course-border);
}

.course-detail-page .lesson-attachment-icon {
    font-size: 18px;
    flex-shrink: 0;
}

.course-detail-page .lesson-attachment-title {
    flex: 1;
    font-size: 14px;
    font-weight: 600;
    color: var(--course-text);
}

.course-detail-page .lesson-attachment-count {
    font-size: 12px;
    font-weight: 500;
    color: var(--course-text-muted);
    background: #fff;
    padding: 3px 10px;
    border-radius: 10px;
    border: 1px solid var(--course-border);
}

.course-detail-page .lesson-attachment-group .attachment-list {
    margin-bottom: 0;
}

.course-detail-page .lesson-attachment-group .attachment-item:last-child {
    margin-bottom: 0;
}

/* ==================== 播放器 Tab 切换 ==================== */

.course-player-page .player-tabs {
    margin-bottom: 24px;
}

.course-player-page .player-tabs .tabs-nav {
    display: flex;
    gap: 0;
    background: var(--course-card-bg, #fff);
    border: 1px solid var(--course-border, #e2e8f0);
    border-bottom: none;
    border-radius: 14px 14px 0 0;
    overflow: hidden;
}

.course-player-page .player-tabs .tab-item {
    flex: 1;
    padding: 14px 20px;
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text-muted, #64748b);
    text-align: center;
    cursor: pointer;
    border-bottom: 3px solid transparent;
    transition: var(--course-transition, all 0.2s ease);
    user-select: none;
}

.course-player-page .player-tabs .tab-item:hover {
    color: var(--course-primary, #6366f1);
    background: var(--course-primary-bg, #eef2ff);
}

.course-player-page .player-tabs .tab-item.active {
    color: var(--course-primary, #6366f1);
    border-bottom-color: var(--course-primary, #6366f1);
    background: var(--course-primary-bg, #eef2ff);
}

.course-player-page .player-tabs .tab-count {
    display: inline-block;
    margin-left: 6px;
    padding: 1px 8px;
    font-size: 12px;
    font-weight: 500;
    color: var(--course-text-muted, #64748b);
    background: var(--course-bg, #f1f5f9);
    border-radius: 10px;
    transition: var(--course-transition, all 0.2s ease);
}

.course-player-page .player-tabs .tab-item.active .tab-count {
    color: var(--course-primary, #6366f1);
    background: #fff;
}

.course-player-page .player-tabs .tabs-content {
    background: var(--course-card-bg, #fff);
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: 0 0 14px 14px;
    box-shadow: var(--course-shadow, 0 4px 16px rgba(0,0,0,0.06));
    overflow: hidden;
}

.course-player-page .player-tabs .tab-pane {
    display: none;
    padding: 20px 24px;
}

.course-player-page .player-tabs .tab-pane.active {
    display: block;
}

/* player-tabs 内的进度条样式微调（因为外层已有 padding） */
.course-player-page .player-tabs .tab-pane .course-progress-section {
    margin-bottom: 0;
}

/* player-tabs 内评论区样式适配 */
.course-player-page .player-tabs .comment-form-wrap {
    margin-bottom: 24px;
}

.course-player-page .player-tabs .comment-form {
    display: block;
    width: 100%;
    background: var(--course-card-bg, #fff);
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: 14px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    transition: box-shadow 0.2s ease, border-color 0.2s ease;
    box-sizing: border-box;
}

.course-player-page .player-tabs .comment-form > .comment-rating-row,
.course-player-page .player-tabs .comment-form > .comment-textarea-wrap {
    display: block;
    width: 100%;
    box-sizing: border-box;
}

.course-player-page .player-tabs .comment-form:focus-within {
    border-color: var(--course-primary, #6366f1);
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.12);
}

.course-player-page .player-tabs .comment-textarea-wrap {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.course-player-page .player-tabs .comment-textarea {
    width: 100%;
    min-height: 90px;
    padding: 14px 16px;
    font-size: 14px;
    font-family: var(--course-font, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif);
    color: var(--course-text, #1a202c);
    background: var(--course-bg, #f7f8fa);
    border: 1px solid var(--course-border, #e2e8f0);
    border-radius: 10px;
    resize: vertical;
    box-sizing: border-box;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.course-player-page .player-tabs .comment-textarea:focus {
    outline: none;
    border-color: var(--course-primary, #6366f1);
    background: var(--course-card-bg, #fff);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.course-player-page .player-tabs .comments-list {
    margin-top: 0;
}

/* ========== 课时评分星星 ========== */
.course-player-page .player-tabs .comment-rating-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
    padding: 10px 14px;
    background: var(--course-bg, #f7f8fa);
    border-radius: 10px;
    width: 100%;
    box-sizing: border-box;
    flex-wrap: nowrap;
}

.course-player-page .player-tabs .comment-rating-label {
    font-size: 13px;
    font-weight: 600;
    color: var(--course-text, #1a202c);
    flex-shrink: 0;
}

.course-player-page .player-tabs .comment-stars {
    display: flex;
    gap: 3px;
    cursor: pointer;
    user-select: none;
}

.course-player-page .player-tabs .comment-stars .star {
    font-size: 22px;
    color: #cbd5e0;
    transition: color 0.15s ease, transform 0.15s ease;
    line-height: 1;
}

.course-player-page .player-tabs .comment-stars .star.active,
.course-player-page .player-tabs .comment-stars .star:hover {
    color: #f6ad55;
}

.course-player-page .player-tabs .comment-stars .star:hover {
    transform: scale(1.15);
}

.course-player-page .player-tabs .comment-rating-text {
    font-size: 12px;
    color: var(--course-text-muted, #a0aec0);
    margin-left: auto;
    flex-shrink: 0;
}

/* 评论项中的星级显示 */
.course-player-page .player-tabs .comment-rating-stars {
    display: inline-flex;
    gap: 1px;
    margin: 0 6px;
    vertical-align: middle;
}

.course-player-page .player-tabs .comment-rating-stars .star {
    font-size: 13px;
    color: #e2e8f0;
    line-height: 1;
}

.course-player-page .player-tabs .comment-rating-stars .star.active {
    color: #f6ad55;
}

/* ========== 评论筛选标签栏 ========== */
.course-player-page .player-tabs .comment-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 18px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--course-border, #e2e8f0);
}

.course-player-page .player-tabs .comment-filter-item {
    display: inline-flex;
    align-items: center;
    padding: 5px 14px;
    font-size: 13px;
    font-weight: 500;
    color: var(--course-text-muted, #64748b);
    background: var(--course-bg, #f1f5f9);
    border: 1px solid transparent;
    border-radius: 20px;
    cursor: pointer;
    user-select: none;
    transition: all 0.2s ease;
}

.course-player-page .player-tabs .comment-filter-item:hover {
    color: var(--course-primary, #6366f1);
    background: rgba(99, 102, 241, 0.08);
}

.course-player-page .player-tabs .comment-filter-item.active {
    color: #fff;
    background: var(--course-primary, #6366f1);
    border-color: var(--course-primary, #6366f1);
}

/* ========== 评论评分等级标签 ========== */
.course-player-page .player-tabs .comment-rating-tag {
    display: inline-flex;
    align-items: center;
    padding: 1px 8px;
    font-size: 11px;
    font-weight: 600;
    border-radius: 4px;
    margin: 0 4px;
    line-height: 1.5;
    vertical-align: middle;
}

.course-player-page .player-tabs .comment-rating-tag.tag-good {
    color: #16a34a;
    background: #dcfce7;
}

.course-player-page .player-tabs .comment-rating-tag.tag-medium {
    color: #2563eb;
    background: #dbeafe;
}

.course-player-page .player-tabs .comment-rating-tag.tag-normal {
    color: #ca8a04;
    background: #fef9c3;
}

.course-player-page .player-tabs .comment-rating-tag.tag-bad {
    color: #dc2626;
    background: #fee2e2;
}

@media (max-width: 640px) {
    .course-player-page .player-tabs .tab-item {
        padding: 12px 10px;
        font-size: 13px;
    }

    .course-player-page .player-tabs .tab-pane {
        padding: 16px;
    }

    .course-player-page .player-tabs .comment-form {
        padding: 14px;
        border-radius: 12px;
    }

    .course-player-page .player-tabs .comment-rating-row {
        flex-wrap: wrap;
        gap: 6px;
    }

    .course-player-page .player-tabs .comment-rating-text {
        margin-left: 0;
    }
}

/* ==================== 课程首页响应式 ==================== */

@media (max-width: 900px) {
    .courses-home__inner {
        flex-direction: column;
    }

    .course-sidebar {
        flex: none;
        width: 100%;
        position: static;
        box-shadow: none;
        overflow: visible;
    }

    .course-sidebar__all {
        height: 46px;
        padding: 0 18px;
    }

    .course-banner__track {
        height: 280px;
    }

    .course-banner__content {
        margin-left: 0;
        padding: 32px 24px;
    }

    .course-banner__title {
        font-size: 30px;
    }

    .courses-home .course-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 16px;
    }
}

@media (max-width: 640px) {
    .course-banner__track {
        height: 240px;
    }

    .course-banner__content {
        padding: 24px 18px;
    }

    .course-banner__title {
        font-size: 24px;
    }

    .course-sidebar__group {
        padding: 6px 8px 0;
    }

    .course-sidebar__group-body .course-sidebar__sub {
        padding: 6px 12px;
        border-radius: 14px;
    }

    .course-toolbar .course-search-form {
        max-width: none;
        width: 100%;
    }

    .courses-home .course-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
}