/* 91在线视频 - 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #e91e63;
    --secondary-color: #2196f3;
    --dark-color: #1a1a2e;
    --light-color: #f5f5f5;
    --text-color: #333;
    --border-color: #e0e0e0;
    --gradient-1: linear-gradient(135deg, #e91e63 0%, #9c27b0 100%);
    --gradient-2: linear-gradient(135deg, #2196f3 0%, #00bcd4 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #fff;
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

/* 头部导航 */
header {
    background: #fff;
    box-shadow: 0 2px 10px 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;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

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

.logo img {
    height: 50px;
    width: auto;
}

.logo-text {
    font-size: 24px;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 35px;
}

.nav-menu a {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-color);
    padding: 8px 0;
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.nav-menu a:hover {
    color: var(--primary-color);
}

/* 搜索框 */
.search-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 30px 20px;
}

.search-box {
    max-width: 600px;
    margin: 0 auto;
    position: relative;
}

.search-box input {
    width: 100%;
    padding: 15px 50px 15px 20px;
    font-size: 16px;
    border: 2px solid var(--border-color);
    border-radius: 50px;
    outline: none;
    transition: all 0.3s ease;
}

.search-box input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(233, 30, 99, 0.1);
}

.search-box button {
    position: absolute;
    right: 5px;
    top: 50%;
    transform: translateY(-50%);
    background: var(--gradient-1);
    border: none;
    color: #fff;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.search-box button:hover {
    transform: translateY(-50%) scale(1.05);
}

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

/* 区块标题 */
.section-title {
    text-align: center;
    margin: 60px 0 40px;
}

.section-title h2 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 15px;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-title p {
    font-size: 18px;
    color: #666;
}

/* 视频卡片 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 25px;
    margin-bottom: 60px;
}

.video-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.video-thumbnail {
    position: relative;
    width: 100%;
    padding-top: 56.25%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    overflow: hidden;
}

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

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    width: 70px;
    height: 70px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    z-index: 2;
}

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

.play-button::after {
    content: '';
    width: 0;
    height: 0;
    border-left: 20px solid var(--primary-color);
    border-top: 12px solid transparent;
    border-bottom: 12px solid transparent;
    margin-left: 5px;
}

.video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0);
    transition: all 0.3s ease;
}

.video-card:hover .video-overlay {
    background: rgba(0, 0, 0, 0.3);
}

.video-duration {
    position: absolute;
    bottom: 10px;
    right: 10px;
    background: rgba(0, 0, 0, 0.8);
    color: #fff;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 500;
}

.video-info {
    padding: 18px;
}

.video-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-color);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-meta {
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 14px;
    color: #666;
}

.video-meta span {
    display: flex;
    align-items: center;
    gap: 5px;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 50px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
}

.btn-primary {
    background: var(--gradient-1);
    color: #fff;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(233, 30, 99, 0.3);
}

.btn-secondary {
    background: var(--gradient-2);
    color: #fff;
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(33, 150, 243, 0.3);
}

/* 特色区块 */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.feature-card {
    background: #fff;
    padding: 35px 25px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.feature-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: var(--gradient-1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    color: #fff;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: var(--text-color);
}

.feature-card p {
    font-size: 15px;
    color: #666;
    line-height: 1.7;
}

/* 专家展示 */
.expert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.expert-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    text-align: center;
}

.expert-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.expert-photo {
    width: 100%;
    padding-top: 100%;
    position: relative;
    background: var(--gradient-2);
}

.expert-photo img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.expert-info {
    padding: 20px;
}

.expert-name {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
}

.expert-title {
    font-size: 14px;
    color: var(--primary-color);
    margin-bottom: 12px;
}

.expert-desc {
    font-size: 14px;
    color: #666;
    line-height: 1.6;
    margin-bottom: 15px;
}

/* 页脚 */
footer {
    background: var(--dark-color);
    color: #fff;
    padding: 60px 0 20px;
    margin-top: 80px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3 {
    font-size: 20px;
    margin-bottom: 20px;
    color: #fff;
}

.footer-section p,
.footer-section a {
    font-size: 14px;
    color: #bbb;
    line-height: 2;
}

.footer-section a:hover {
    color: var(--primary-color);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.footer-logo img {
    height: 45px;
}

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px 20px 0;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    color: #888;
    font-size: 14px;
}

.qr-codes {
    display: flex;
    gap: 20px;
    margin-top: 15px;
    justify-content: center;
}

.qr-code {
    text-align: center;
}

.qr-code img {
    width: 100px;
    height: 100px;
    background: #fff;
    padding: 8px;
    border-radius: 8px;
    margin-bottom: 8px;
}

.qr-code p {
    font-size: 12px;
    color: #888;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header-container {
        flex-wrap: wrap;
        height: auto;
        padding: 15px 20px;
    }
    
    .nav-menu {
        width: 100%;
        justify-content: space-around;
        gap: 15px;
        margin-top: 15px;
        flex-wrap: wrap;
    }
    
    .nav-menu a {
        font-size: 14px;
    }
    
    .section-title h2 {
        font-size: 28px;
    }
    
    .video-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* 加载动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* 懒加载占位 */
.lazy-load {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

@keyframes loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}