/* 基础样式重置 */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif; line-height: 1.6; color: #333; background-color: #f8f9fa; }
a { text-decoration: none; color: inherit; }
ul, ol { list-style: none; }
img, video { max-width: 100%; height: auto; display: block; }

/* 容器与布局 */
.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 15px; }
.section { padding: 60px 0; background-color: #fff; margin-bottom: 20px; }
.section-title { text-align: center; font-size: 28px; margin-bottom: 40px; color: #222; font-weight: bold; position: relative; }
.section-title::after { content: ''; display: block; width: 60px; height: 3px; background-color: #ff4d4f; margin: 10px auto 0; }

/* 头部导航 */
.header { background-color: #fff; box-shadow: 0 2px 10px rgba(0,0,0,0.1); position: sticky; top: 0; z-index: 1000; }
.header-inner { display: flex; justify-content: space-between; align-items: center; height: 80px; }
.logo-area { display: flex; align-items: center; gap: 10px; }
.logo-img { height: 50px; }
.logo-text { font-size: 24px; font-weight: bold; color: #222; }
.nav { display: flex; gap: 20px; }
.nav a { font-size: 16px; font-weight: 500; padding: 10px 5px; transition: color 0.3s; }
.nav a:hover, .nav a.active { color: #ff4d4f; }

/* 搜索框 (仅视觉) */
.search-bar { background-color: #f1f2f6; padding: 15px 0; border-bottom: 1px solid #e1e2e6; }
.search-inner { display: flex; justify-content: center; }
.search-input { width: 100%; max-width: 600px; padding: 12px 20px; border: 1px solid #ddd; border-radius: 24px 0 0 24px; outline: none; font-size: 16px; }
.search-btn { padding: 12px 30px; background-color: #ff4d4f; color: #fff; border: none; border-radius: 0 24px 24px 0; cursor: pointer; font-size: 16px; }

/* 轮播图/Banner */
.banner { position: relative; width: 100%; overflow: hidden; background-color: #000; }
.banner-img { width: 100%; max-height: 600px; object-fit: cover; opacity: 0.8; }
.banner-content { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); text-align: center; color: #fff; width: 80%; }
.banner-title { font-size: 48px; font-weight: bold; margin-bottom: 20px; text-shadow: 2px 2px 4px rgba(0,0,0,0.5); }
.banner-desc { font-size: 20px; margin-bottom: 30px; text-shadow: 1px 1px 2px rgba(0,0,0,0.5); }

/* 视频卡片网格 */
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 20px; }
.video-card { background: #fff; border-radius: 8px; overflow: hidden; box-shadow: 0 4px 15px rgba(0,0,0,0.05); transition: transform 0.3s; }
.video-card:hover { transform: translateY(-5px); box-shadow: 0 8px 25px rgba(0,0,0,0.1); }
.video-cover { position: relative; padding-top: 56.25%; /* 16:9 */ background-color: #eee; overflow: hidden; }
.video-cover img { position: absolute; top: 0; left: 0; width: 100%; height: 100%; object-fit: cover; }
.play-btn-overlay { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.3); display: flex; justify-content: center; align-items: center; opacity: 0; transition: opacity 0.3s; }
.video-card:hover .play-btn-overlay { opacity: 1; }
.play-icon { width: 60px; height: 60px; background: rgba(255,255,255,0.9); border-radius: 50%; display: flex; justify-content: center; align-items: center; }
.play-icon::after { content: ''; display: block; border-left: 20px solid #ff4d4f; border-top: 12px solid transparent; border-bottom: 12px solid transparent; margin-left: 5px; }
.video-info { padding: 15px; }
.video-title { font-size: 16px; font-weight: bold; margin-bottom: 10px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.video-meta { display: flex; justify-content: space-between; color: #999; font-size: 12px; }
.video-tags { margin-top: 10px; display: flex; gap: 5px; flex-wrap: wrap; }
.tag { background: #f0f2f5; color: #666; padding: 2px 8px; border-radius: 4px; font-size: 12px; }

/* 特色模块 */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.feature-item { text-align: center; padding: 30px; background: #fff; border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,0.05); }
.feature-icon { font-size: 40px; color: #ff4d4f; margin-bottom: 20px; }
.feature-title { font-size: 20px; font-weight: bold; margin-bottom: 15px; }

/* 专家展示 */
.expert-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 30px; }
.expert-card { text-align: center; padding: 20px; border: 1px solid #eee; border-radius: 8px; }
.expert-avatar { width: 120px; height: 120px; border-radius: 50%; margin: 0 auto 15px; object-fit: cover; border: 3px solid #ff4d4f; }
.expert-name { font-size: 18px; font-weight: bold; margin-bottom: 5px; }
.expert-title { color: #ff4d4f; font-size: 14px; margin-bottom: 15px; }
.expert-desc { font-size: 14px; color: #666; margin-bottom: 15px; text-align: left; }
.expert-btn { display: inline-block; padding: 8px 20px; border: 1px solid #ff4d4f; color: #ff4d4f; border-radius: 20px; font-size: 14px; transition: all 0.3s; }
.expert-btn:hover { background: #ff4d4f; color: #fff; }

/* 评价与FAQ */
.review-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.review-card { background: #f9f9f9; padding: 20px; border-radius: 8px; border-left: 4px solid #ff4d4f; }
.review-user { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.review-avatar { width: 40px; height: 40px; border-radius: 50%; background: #ddd; }
.review-name { font-weight: bold; }
.review-date { color: #999; font-size: 12px; }
.review-content { color: #555; font-style: italic; }

.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { margin-bottom: 15px; border: 1px solid #eee; border-radius: 8px; overflow: hidden; }
.faq-q { padding: 15px 20px; background: #f9f9f9; font-weight: bold; cursor: pointer; display: flex; justify-content: space-between; }
.faq-q::after { content: '+'; color: #ff4d4f; }
.faq-a { padding: 15px 20px; display: none; border-top: 1px solid #eee; }

/* 合作伙伴 */
.partner-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 30px; }
.partner-logo { height: 60px; filter: grayscale(100%); opacity: 0.6; transition: all 0.3s; }
.partner-logo:hover { filter: grayscale(0); opacity: 1; }

/* 底部与联系方式 */
.footer { background: #222; color: #ccc; padding: 60px 0 20px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 30px; margin-bottom: 40px; }
.footer-title { color: #fff; font-size: 18px; margin-bottom: 20px; }
.footer-contact li { margin-bottom: 10px; display: flex; align-items: flex-start; gap: 10px; }
.qrcode-area { display: flex; gap: 20px; }
.qrcode-item { text-align: center; }
.qrcode-img { width: 100px; height: 100px; background: #fff; padding: 5px; margin-bottom: 10px; }
.copyright { text-align: center; padding-top: 20px; border-top: 1px solid #444; font-size: 14px; }

/* 内页特定样式 */
.page-header { background: #f8f9fa; padding: 40px 0; border-bottom: 1px solid #eee; }
.breadcrumb { margin-bottom: 15px; font-size: 14px; color: #666; }
.breadcrumb a { color: #ff4d4f; }
.page-title { font-size: 32px; font-weight: bold; color: #222; margin-bottom: 15px; }
.page-desc { font-size: 16px; color: #555; max-width: 800px; }
.content-area { display: flex; gap: 30px; margin-top: 40px; }
.main-content { flex: 3; }
.sidebar { flex: 1; }
.widget { background: #fff; padding: 20px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,0.05); margin-bottom: 20px; }
.widget-title { font-size: 18px; font-weight: bold; margin-bottom: 15px; padding-bottom: 10px; border-bottom: 1px solid #eee; }

/* 响应式适配 */
@media (max-width: 768px) {
    .header-inner { flex-direction: column; height: auto; padding: 15px 0; gap: 15px; }
    .nav { flex-wrap: wrap; justify-content: center; }
    .banner-title { font-size: 32px; }
    .feature-grid, .review-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 40px; }
    .content-area { flex-direction: column; }
}