/* 小马拉大车 网站样式 - 完全原创设计 v2.0 */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #E8507A;
    --secondary-color: #FF7B54;
    --accent-color: #9B59B6;
    --dark-bg: #1a1a2e;
    --light-bg: #f8f9fa;
    --text-dark: #2c3e50;
    --text-light: #ffffff;
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

/* 无障碍辅助 */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    border: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: var(--light-bg);
}

/* ===== 头部导航 ===== */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 15px;
    flex-shrink: 0;
}

.logo-img {
    height: 50px;
    width: auto;
    border-radius: 8px;
}

.logo-text {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-light);
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
    white-space: nowrap;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 5px;
    flex-wrap: nowrap;
}

.nav-menu a {
    color: var(--text-light);
    text-decoration: none;
    padding: 10px 18px;
    border-radius: 8px;
    font-weight: 500;
    transition: var(--transition);
    font-size: 15px;
    white-space: nowrap;
}

.nav-menu a:hover,
.nav-menu a.active {
    background: rgba(255,255,255,0.25);
    transform: translateY(-2px);
}

.mobile-menu-btn {
    display: none;
    background: rgba(255,255,255,0.2);
    border: none;
    color: white;
    font-size: 22px;
    padding: 8px 14px;
    border-radius: 8px;
    cursor: pointer;
}

/* ===== 搜索框 ===== */
.search-container {
    max-width: 860px;
    margin: 35px auto 0;
    padding: 0 20px 20px;
}

.search-box {
    position: relative;
    width: 100%;
}

.search-input {
    width: 100%;
    padding: 18px 140px 18px 25px;
    font-size: 16px;
    border: 2px solid #e0e0e0;
    border-radius: var(--border-radius);
    outline: none;
    transition: var(--transition);
    background: white;
}

.search-input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(232, 80, 122, 0.1);
}

.search-btn {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    color: white;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-size: 15px;
}

.search-btn:hover {
    transform: translateY(-50%) scale(1.05);
    box-shadow: 0 4px 12px rgba(232, 80, 122, 0.3);
}

/* 热搜标签 */
.hot-tags {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
    font-size: 13px;
}

.hot-tag-label {
    color: #E8507A;
    font-weight: 600;
}

.hot-tag {
    color: #666;
    text-decoration: none;
    padding: 4px 12px;
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 20px;
    transition: var(--transition);
    font-size: 13px;
}

.hot-tag:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* ===== 面包屑 ===== */
.breadcrumb-nav {
    max-width: 1400px;
    margin: 0 auto;
    padding: 12px 20px;
    font-size: 14px;
    color: #888;
}

.breadcrumb-inner {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
}

/* ===== Hero Banner ===== */
.hero-section {
    position: relative;
    min-height: 520px;
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(232, 80, 122, 0.88), rgba(45, 27, 105, 0.88));
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: white;
    max-width: 960px;
    padding: 60px 20px;
}

.hero-title {
    font-size: 52px;
    font-weight: 800;
    margin-bottom: 20px;
    text-shadow: 3px 3px 6px rgba(0,0,0,0.3);
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 22px;
    margin-bottom: 35px;
    opacity: 0.95;
    font-weight: 300;
}

.hero-cta {
    display: inline-block;
    padding: 16px 40px;
    background: white;
    color: var(--primary-color);
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 700;
    font-size: 18px;
    transition: var(--transition);
    box-shadow: 0 8px 20px rgba(0,0,0,0.2);
}

.hero-cta:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 28px rgba(0,0,0,0.3);
}

/* ===== 容器 ===== */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 60px 20px;
}

/* ===== 区块标题 ===== */
.section-title {
    font-size: 38px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 12px;
    color: var(--text-dark);
}

.section-subtitle {
    text-align: center;
    font-size: 17px;
    color: #666;
    margin-bottom: 45px;
    line-height: 1.6;
}

/* ===== 视频标签栏 ===== */
.video-tags-bar {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 30px;
    justify-content: center;
}

.vtag {
    padding: 8px 20px;
    border-radius: 20px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    background: #f0f0f0;
    color: #555;
    transition: var(--transition);
}

.vtag:hover,
.vtag-active {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

/* ===== 视频网格 ===== */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 28px;
    margin-bottom: 40px;
}

.video-card {
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: var(--transition);
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 35px rgba(0,0,0,0.15);
}

.video-thumbnail {
    position: relative;
    width: 100%;
    padding-top: 56.25%;
    overflow: hidden;
    background: #111;
}

.video-thumbnail img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.video-card:hover .video-thumbnail img {
    transform: scale(1.08);
}

/* 播放按钮覆盖层 */
.play-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 72px;
    height: 72px;
    background: rgba(232, 80, 122, 0.92);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
    z-index: 3;
    box-shadow: 0 4px 20px rgba(232,80,122,0.5);
}

.video-card:hover .play-overlay {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.1);
}

.play-icon {
    width: 0;
    height: 0;
    border-left: 22px solid white;
    border-top: 13px solid transparent;
    border-bottom: 13px solid transparent;
    margin-left: 6px;
}

/* 视频时长标签 */
.video-duration-badge {
    position: absolute;
    bottom: 10px;
    right: 10px;
    background: rgba(0,0,0,0.75);
    color: white;
    padding: 3px 8px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 600;
    z-index: 2;
}

/* 视频分类标签 */
.video-cat-badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background: var(--primary-color);
    color: white;
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
    z-index: 2;
}

/* H5视频预览层 */
.video-preview-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.3s;
    z-index: 1;
    pointer-events: none;
}

.video-card:hover .video-preview-layer {
    opacity: 1;
}

.preview-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.video-info {
    padding: 18px 20px;
}

.video-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-dark);
    line-height: 1.45;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: #888;
    flex-wrap: wrap;
    gap: 5px;
}

.video-stats {
    display: flex;
    gap: 12px;
}

/* ===== 专家团队 ===== */
.experts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 35px;
    margin-bottom: 40px;
}

.expert-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 30px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: var(--transition);
    border-top: 4px solid var(--primary-color);
}

.expert-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 16px 35px rgba(232,80,122,0.15);
}

.expert-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    object-position: top;
    margin: 0 auto 20px;
    border: 5px solid var(--primary-color);
    display: block;
}

.expert-name {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-dark);
}

.expert-title {
    font-size: 15px;
    color: var(--primary-color);
    margin-bottom: 15px;
    font-weight: 600;
}

.expert-bio {
    font-size: 14px;
    color: #666;
    line-height: 1.6;
    margin-bottom: 18px;
    text-align: left;
}

.expert-btn {
    display: inline-block;
    padding: 10px 25px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: var(--transition);
}

.expert-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(232, 80, 122, 0.3);
}

/* ===== FAQ ===== */
.faq-container {
    max-width: 920px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    border-radius: var(--border-radius);
    margin-bottom: 18px;
    padding: 25px 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    transition: var(--transition);
    border-left: 4px solid var(--primary-color);
}

.faq-item:hover {
    box-shadow: 0 6px 20px rgba(232,80,122,0.12);
}

.faq-question {
    font-size: 17px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
    display: flex;
    align-items: flex-start;
    gap: 12px;
}

.faq-question::before {
    content: "Q";
    display: inline-flex;
    width: 30px;
    height: 30px;
    min-width: 30px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 50%;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 14px;
}

.faq-answer {
    font-size: 15px;
    color: #555;
    line-height: 1.7;
    padding-left: 42px;
}

/* ===== 用户评论 ===== */
.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 22px;
}

.review-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    transition: var(--transition);
}

.review-card:hover {
    box-shadow: 0 8px 25px rgba(0,0,0,0.12);
    transform: translateY(-3px);
}

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

.review-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 18px;
    flex-shrink: 0;
}

.review-user { flex: 1; }

.review-name {
    font-weight: 700;
    font-size: 15px;
    color: var(--text-dark);
}

.review-date {
    font-size: 12px;
    color: #aaa;
    margin-top: 2px;
}

.review-text {
    font-size: 14px;
    color: #555;
    line-height: 1.65;
}

/* ===== 页脚 ===== */
.footer {
    background: linear-gradient(135deg, #1a1a2e, #2d1b69);
    color: rgba(255,255,255,0.8);
    padding: 60px 0 0;
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3 {
    color: white;
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 18px;
    padding-bottom: 10px;
    border-bottom: 2px solid rgba(232,80,122,0.5);
}

.footer-section p {
    font-size: 14px;
    line-height: 1.7;
    margin-bottom: 8px;
}

.footer-section a {
    color: rgba(255,255,255,0.75);
    text-decoration: none;
    font-size: 14px;
    line-height: 2.2;
    transition: var(--transition);
    display: inline-block;
}

.footer-section a:hover {
    color: var(--primary-color);
    transform: translateX(4px);
}

.qrcode-container {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.qrcode-item {
    text-align: center;
}

.qrcode-item img {
    width: 90px;
    height: 90px;
    border-radius: 8px;
    background: white;
    padding: 6px;
    display: block;
}

.qrcode-label {
    font-size: 12px;
    color: rgba(255,255,255,0.7);
    margin-top: 6px;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 25px 0;
    text-align: center;
    font-size: 14px;
    color: rgba(255,255,255,0.6);
}

/* ===== 动画效果 ===== */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(25px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

/* ===== 返回顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 22px;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(232,80,122,0.4);
    transition: var(--transition);
    z-index: 999;
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(232,80,122,0.5);
}

.back-to-top.visible {
    display: flex;
}

/* ===== 移动端响应式 ===== */
@media (max-width: 1024px) {
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    .hero-title { font-size: 40px; }
}

@media (max-width: 768px) {
    .header-container { height: 65px; }
    .logo-text { font-size: 22px; }
    .logo-img { height: 40px; }
    
    .nav-menu {
        display: none;
        position: fixed;
        top: 65px;
        left: 0;
        right: 0;
        background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
        flex-direction: column;
        padding: 20px;
        gap: 5px;
        z-index: 999;
        box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    }
    
    .nav-menu.open { display: flex; }
    .nav-menu a { padding: 14px 20px; font-size: 16px; }
    .mobile-menu-btn { display: flex; align-items: center; }
    
    .hero-title { font-size: 30px; }
    .hero-subtitle { font-size: 16px; }
    .section-title { font-size: 28px; }
    
    .footer-grid { grid-template-columns: 1fr; gap: 30px; }
    
    .video-grid { grid-template-columns: 1fr; }
    .experts-grid { grid-template-columns: 1fr; }
    .reviews-grid { grid-template-columns: 1fr; }
    
    .search-input { padding: 15px 120px 15px 18px; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 24px; }
    .container { padding: 40px 15px; }
    .hero-content { padding: 40px 15px; }
}