/**
 * ============================================================================
 * 课程模块样式 - 暗金轻奢主题
 * ============================================================================
 * 前缀: courses-, course-, learn-
 * 主题色: #C9A96E (金色)
 * ============================================================================
 */

/* ==================== CSS变量 ==================== */
:root {
    --course-primary: #C9A96E;
    --course-primary-light: #D4B87A;
    --course-primary-dark: #B8943F;
    --course-primary-bg: rgba(201, 169, 110, 0.1);
    
    --course-bg-dark: #0D1117;
    --course-bg-card: #161B22;
    --course-bg-input: #21262D;
    
    --course-text-primary: #E6EDF3;
    --course-text-secondary: #8B949E;
    --course-text-muted: #484F58;
    
    --course-border: rgba(201, 169, 110, 0.12);
    --course-border-hover: rgba(201, 169, 110, 0.25);
    
    --course-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    --course-shadow-gold: 0 4px 12px rgba(201, 169, 110, 0.15);
    
    --course-radius: 12px;
    --course-radius-sm: 8px;
    
    --course-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==================== 课程列表页 ==================== */
.courses-page {
    padding: 24px;
    max-width: 1400px;
    margin: 0 auto;
}

/* 页面头部 */
.courses-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 32px;
    padding: 32px;
    background: linear-gradient(135deg, rgba(201, 169, 110, 0.08) 0%, rgba(201, 169, 110, 0.02) 100%);
    border: 1px solid var(--course-border);
    border-radius: 16px;
}

.courses-header__title {
    font-size: 32px;
    font-weight: 700;
    color: var(--course-text-primary);
    margin: 0 0 8px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.courses-header__title i {
    color: var(--course-primary);
}

.courses-header__desc {
    font-size: 16px;
    color: var(--course-text-secondary);
    margin: 0;
}

.courses-stat {
    text-align: center;
    padding: 16px 32px;
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.courses-stat__value {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: var(--course-primary);
}

.courses-stat__label {
    font-size: 14px;
    color: var(--course-text-secondary);
}

/* 工具栏 */
.courses-toolbar {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 24px;
    padding: 20px;
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
}

.courses-toolbar__left {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.courses-toolbar__right {
    display: flex;
    gap: 12px;
    align-items: center;
}

.courses-filter-group {
    display: flex;
    align-items: center;
    gap: 12px;
}

.courses-filter-label {
    font-size: 14px;
    color: var(--course-text-secondary);
    font-weight: 500;
}

.courses-filter-tabs {
    display: flex;
    gap: 4px;
}

.courses-filter-tab {
    padding: 8px 16px;
    font-size: 14px;
    color: var(--course-text-secondary);
    border-radius: var(--course-radius-sm);
    transition: var(--course-transition);
    text-decoration: none;
}

.courses-filter-tab:hover {
    color: var(--course-primary-light);
    background: var(--course-primary-bg);
}

.courses-filter-tab.active {
    background: linear-gradient(135deg, var(--course-primary), var(--course-primary-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(201, 169, 110, 0.3);
}

/* 排序和搜索 */
.courses-sort select {
    padding: 10px 16px;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    background: var(--course-bg-input);
    color: var(--course-text-primary);
    font-size: 14px;
    cursor: pointer;
}

.courses-sort select:focus {
    outline: none;
    border-color: var(--course-primary);
}

.courses-search form {
    display: flex;
    gap: 8px;
}

.courses-search input {
    width: 200px;
    padding: 10px 16px;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    background: var(--course-bg-input);
    color: var(--course-text-primary);
    font-size: 14px;
}

.courses-search input:focus {
    outline: none;
    border-color: var(--course-primary);
}

.courses-search button {
    padding: 10px 16px;
    background: linear-gradient(135deg, var(--course-primary), var(--course-primary-dark));
    border: none;
    border-radius: var(--course-radius-sm);
    color: white;
    cursor: pointer;
    transition: var(--course-transition);
}

.courses-search button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(201, 169, 110, 0.3);
}

/* 课程网格 */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
}

.course-card {
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    overflow: hidden;
    transition: var(--course-transition);
}

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

.course-card__link {
    display: block;
    text-decoration: none;
    color: inherit;
}

.course-card__cover {
    position: relative;
    aspect-ratio: 16/9;
    overflow: hidden;
}

.course-card__cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--course-transition);
}

.course-card:hover .course-card__cover img {
    transform: scale(1.05);
}

.course-card__level {
    position: absolute;
    top: 12px;
    left: 12px;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.course-card__level--beginner {
    background: #10B981;
    color: white;
}

.course-card__level--intermediate {
    background: #F59E0B;
    color: white;
}

.course-card__level--advanced {
    background: #EF4444;
    color: white;
}

.course-card__body {
    padding: 20px;
}

.course-card__title {
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0 0 12px;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-card__meta {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 12px;
    font-size: 13px;
    color: var(--course-text-secondary);
}

.course-card__meta i {
    color: var(--course-primary);
    margin-right: 4px;
}

.course-card__footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 12px;
    border-top: 1px solid var(--course-border);
}

.course-card__price--current {
    font-size: 18px;
    font-weight: 700;
    color: var(--course-primary);
}

.course-card__price--free {
    font-size: 16px;
    font-weight: 600;
    color: #10B981;
}

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

/* 分页 */
.courses-pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-top: 32px;
}

.courses-pagination__btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 16px;
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius-sm);
    background: var(--course-bg-card);
    color: var(--course-text-secondary);
    font-size: 14px;
    transition: var(--course-transition);
    text-decoration: none;
}

.courses-pagination__btn:hover {
    border-color: var(--course-primary);
    color: var(--course-primary);
    background: var(--course-primary-bg);
}

.courses-pagination__btn.active {
    background: linear-gradient(135deg, var(--course-primary), var(--course-primary-dark));
    color: white;
    border-color: var(--course-primary);
    box-shadow: 0 4px 12px rgba(201, 169, 110, 0.3);
}

.courses-pagination__ellipsis {
    color: var(--course-text-muted);
    padding: 0 8px;
}

/* 空状态 */
.courses-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 80px 20px;
    text-align: center;
}

.courses-empty__icon {
    width: 120px;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--course-primary-bg);
    border-radius: 50%;
    margin-bottom: 24px;
}

.courses-empty__icon i {
    font-size: 48px;
    color: var(--course-primary);
}

.courses-empty__title {
    font-size: 20px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0 0 8px;
}

.courses-empty__desc {
    font-size: 14px;
    color: var(--course-text-muted);
    margin: 0;
}

/* ==================== 课程详情页 ==================== */
.course-detail-page {
    padding: 24px;
    max-width: 1400px;
    margin: 0 auto;
}

.course-header {
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    overflow: hidden;
    margin-bottom: 24px;
}

.course-header__container {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 32px;
    padding: 32px;
}

.course-header__cover {
    border-radius: var(--course-radius);
    overflow: hidden;
}

.course-header__cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.course-header__info {
    display: flex;
    flex-direction: column;
}

.course-header__meta {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
}

.course-header__level {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.course-header__level--beginner { background: #10B981; color: white; }
.course-header__level--intermediate { background: #F59E0B; color: white; }
.course-header__level--advanced { background: #EF4444; color: white; }

.course-header__category {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--course-text-secondary);
}

.course-header__category i {
    color: var(--course-primary);
}

.course-header__title {
    font-size: 28px;
    font-weight: 700;
    color: var(--course-text-primary);
    margin: 0 0 12px;
}

.course-header__subtitle {
    font-size: 16px;
    color: var(--course-text-secondary);
    margin: 0 0 20px;
}

.course-header__stats {
    display: flex;
    gap: 24px;
    margin-bottom: 20px;
}

.course-header__stat {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--course-text-secondary);
}

.course-header__stat i {
    color: var(--course-primary);
}

.course-header__mentor {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
    padding: 16px;
    background: var(--course-bg-input);
    border-radius: var(--course-radius-sm);
}

.course-header__mentor-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--course-primary);
}

.course-header__mentor-info {
    display: flex;
    flex-direction: column;
}

.course-header__mentor-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text-primary);
}

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

.course-header__action {
    margin-top: auto;
}

.course-header__price {
    margin-bottom: 16px;
}

.course-header__price--current {
    font-size: 32px;
    font-weight: 700;
    color: var(--course-primary);
}

.course-header__price--original {
    font-size: 18px;
    color: var(--course-text-muted);
    text-decoration: line-through;
    margin-left: 12px;
}

.course-header__price--free {
    font-size: 24px;
    font-weight: 600;
    color: #10B981;
}

.course-header__btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 32px;
    border-radius: var(--course-radius-sm);
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--course-transition);
}

.course-header__btn--primary {
    background: linear-gradient(135deg, var(--course-primary), var(--course-primary-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(201, 169, 110, 0.3);
}

.course-header__btn--primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(201, 169, 110, 0.4);
}

/* 课程主体内容 */
.course-content {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 24px;
}

.course-content__main {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.course-section {
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    padding: 24px;
}

.course-section__title {
    font-size: 18px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0 0 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.course-section__title i {
    color: var(--course-primary);
}

.course-section__count {
    font-size: 14px;
    color: var(--course-text-muted);
    font-weight: 400;
    margin-left: auto;
}

.course-section__body {
    font-size: 15px;
    color: var(--course-text-secondary);
    line-height: 1.8;
}

/* 课程章节 */
.course-chapters {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.course-chapter {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px;
    background: var(--course-bg-input);
    border-radius: var(--course-radius-sm);
    transition: var(--course-transition);
}

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

.course-chapter--locked {
    opacity: 0.6;
}

.course-chapter__number {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: 50%;
    font-size: 14px;
    font-weight: 600;
    color: var(--course-primary);
}

.course-chapter__info {
    flex: 1;
}

.course-chapter__info h4 {
    font-size: 15px;
    font-weight: 500;
    color: var(--course-text-primary);
    margin: 0 0 4px;
}

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

.course-chapter__play,
.course-chapter__lock {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.course-chapter__play {
    background: linear-gradient(135deg, var(--course-primary), var(--course-primary-dark));
    color: white;
}

.course-chapter__lock {
    background: var(--course-bg-card);
    color: var(--course-text-muted);
}

/* 侧边栏 */
.course-content__sidebar {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.course-sidebar__section {
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    padding: 20px;
}

.course-sidebar__title {
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0 0 16px;
}

.course-related {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.course-related__item {
    display: flex;
    gap: 12px;
    text-decoration: none;
    transition: var(--course-transition);
}

.course-related__item:hover {
    opacity: 0.8;
}

.course-related__item img {
    width: 80px;
    height: 60px;
    object-fit: cover;
    border-radius: var(--course-radius-sm);
}

.course-related__info {
    flex: 1;
}

.course-related__info h4 {
    font-size: 14px;
    font-weight: 500;
    color: var(--course-text-primary);
    margin: 0 0 4px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

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

/* ==================== 学习页面 ==================== */
.course-learn-page {
    display: grid;
    grid-template-columns: 1fr 320px;
    grid-template-rows: auto 1fr;
    gap: 0;
    height: calc(100vh - 80px);
    background: var(--course-bg-dark);
}

.learn-header {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    background: var(--course-bg-card);
    border-bottom: 1px solid var(--course-border);
}

.learn-header__back {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--course-text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: var(--course-transition);
}

.learn-header__back:hover {
    color: var(--course-primary);
}

.learn-header__title {
    font-size: 16px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0;
}

.learn-header__progress {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--course-text-secondary);
}

.learn-progress {
    width: 120px;
    height: 6px;
    background: var(--course-bg-input);
    border-radius: 3px;
    overflow: hidden;
}

.learn-progress__bar {
    height: 100%;
    background: linear-gradient(90deg, var(--course-primary), var(--course-primary-light));
    transition: width 0.3s ease;
}

.learn-content {
    padding: 24px;
    overflow-y: auto;
}

.learn-video {
    aspect-ratio: 16/9;
    background: #000;
    border-radius: var(--course-radius);
    overflow: hidden;
    margin-bottom: 24px;
}

.learn-video video {
    width: 100%;
    height: 100%;
}

.learn-video__placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--course-text-muted);
}

.learn-video__placeholder i {
    font-size: 48px;
    margin-bottom: 12px;
}

.learn-chapter-info {
    background: var(--course-bg-card);
    border: 1px solid var(--course-border);
    border-radius: var(--course-radius);
    padding: 20px;
}

.learn-chapter-info h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0 0 8px;
}

.learn-chapter-info p {
    font-size: 14px;
    color: var(--course-text-secondary);
    margin: 0;
}

.learn-sidebar {
    background: var(--course-bg-card);
    border-left: 1px solid var(--course-border);
    display: flex;
    flex-direction: column;
}

.learn-sidebar__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--course-border);
}

.learn-sidebar__header h3 {
    font-size: 15px;
    font-weight: 600;
    color: var(--course-text-primary);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 8px;
}

.learn-sidebar__header h3 i {
    color: var(--course-primary);
}

.learn-sidebar__header span {
    font-size: 13px;
    color: var(--course-text-muted);
}

.learn-chapters {
    flex: 1;
    overflow-y: auto;
    padding: 12px;
}

.learn-chapter {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: var(--course-radius-sm);
    text-decoration: none;
    transition: var(--course-transition);
}

.learn-chapter:hover,
.learn-chapter.active {
    background: var(--course-primary-bg);
}

.learn-chapter__number {
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--course-bg-input);
    border-radius: 50%;
    font-size: 12px;
    color: var(--course-text-secondary);
}

.learn-chapter.active .learn-chapter__number {
    background: var(--course-primary);
    color: white;
}

.learn-chapter__info {
    flex: 1;
}

.learn-chapter__info h4 {
    font-size: 14px;
    font-weight: 500;
    color: var(--course-text-primary);
    margin: 0 0 2px;
}

.learn-chapter__info span {
    font-size: 12px;
    color: var(--course-text-muted);
}

.learn-chapter__playing {
    color: var(--course-primary);
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .course-header__container {
        grid-template-columns: 1fr;
    }
    
    .course-header__cover {
        max-width: 400px;
    }
    
    .course-content {
        grid-template-columns: 1fr;
    }
    
    .course-content__sidebar {
        order: -1;
    }
    
    .course-learn-page {
        grid-template-columns: 1fr;
        grid-template-rows: auto auto 1fr;
    }
    
    .learn-sidebar {
        border-left: none;
        border-top: 1px solid var(--course-border);
        max-height: 300px;
    }
}

@media (max-width: 768px) {
    .courses-page {
        padding: 16px;
    }
    
    .courses-header {
        flex-direction: column;
        text-align: center;
        padding: 24px;
    }
    
    .courses-header__title {
        font-size: 24px;
    }
    
    .courses-toolbar__left {
        flex-direction: column;
    }
    
    .courses-filter-tabs {
        flex-wrap: wrap;
    }
    
    .courses-toolbar__right {
        flex-direction: column;
        align-items: stretch;
    }
    
    .courses-search form {
        flex-direction: column;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .course-header__container {
        padding: 20px;
    }
    
    .course-header__title {
        font-size: 22px;
    }
    
    .course-header__stats {
        flex-wrap: wrap;
    }
}