:root {
  --primary: #FF2D78;
  --secondary: #8B5CF6;
  --dark: #1a0a2e;
  --light: #f8f9fa;
  --gray: #6c757d;
  --bg: #ffffff;
  --card-bg: #f8f9fa;
  --gradient: linear-gradient(135deg, var(--primary), var(--secondary));
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif; }
body { background: var(--bg); color: #333; line-height: 1.6; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 15px; }

/* Header */
header { background: #fff; box-shadow: 0 2px 10px rgba(0,0,0,0.05); position: sticky; top: 0; z-index: 100; }
.header-inner { display: flex; justify-content: space-between; align-items: center; height: 80px; }
.logo img { height: 50px; }
.nav { display: flex; gap: 25px; }
.nav a { font-weight: 600; font-size: 16px; transition: color 0.3s; }
.nav a:hover { color: var(--primary); }

/* Search Bar */
.search-wrap { background: #f1f1f1; padding: 10px 0; }
.search-box { display: flex; max-width: 600px; margin: 0 auto; border-radius: 30px; overflow: hidden; border: 2px solid var(--primary); }
.search-input { flex: 1; padding: 12px 20px; border: none; outline: none; font-size: 15px; }
.search-btn { background: var(--gradient); color: #fff; border: none; padding: 0 30px; cursor: pointer; font-weight: bold; }

/* Hero */
.hero { position: relative; height: 500px; display: flex; align-items: center; justify-content: center; text-align: center; color: #fff; overflow: hidden; }
.hero-bg { position: absolute; top: 0; left: 0; width: 100%; height: 100%; object-fit: cover; z-index: -1; }
.hero-overlay { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background: rgba(26,10,46,0.6); z-index: 0; }
.hero-content { position: relative; z-index: 1; max-width: 800px; padding: 20px; }
.hero h1 { font-size: 48px; margin-bottom: 20px; text-shadow: 0 2px 10px rgba(0,0,0,0.5); }
.hero p { font-size: 20px; margin-bottom: 30px; opacity: 0.9; }
.btn { display: inline-block; padding: 12px 30px; background: var(--gradient); color: #fff; border-radius: 30px; font-weight: bold; transition: transform 0.3s; }
.btn:hover { transform: translateY(-2px); }

/* Section */
.section { padding: 80px 0; }
.section-title { text-align: center; font-size: 32px; margin-bottom: 40px; position: relative; padding-bottom: 15px; }
.section-title::after { content: ''; position: absolute; bottom: 0; left: 50%; transform: translateX(-50%); width: 60px; height: 3px; background: var(--gradient); border-radius: 3px; }

/* Video Grid */
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 30px; }
.video-card { background: var(--card-bg); border-radius: 12px; overflow: hidden; box-shadow: 0 5px 15px rgba(0,0,0,0.05); transition: transform 0.3s; cursor: pointer; }
.video-card:hover { transform: translateY(-5px); }
.video-thumb { position: relative; aspect-ratio: 16/9; }
.video-thumb img { width: 100%; height: 100%; object-fit: cover; }
.play-icon { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); width: 50px; height: 50px; background: rgba(255,45,120,0.8); border-radius: 50%; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 24px; opacity: 0; transition: opacity 0.3s; }
.video-card:hover .play-icon { opacity: 1; }
.video-info { padding: 20px; }
.video-title { font-size: 18px; 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: var(--gray); font-size: 14px; }
.video-tag { background: rgba(139,92,246,0.1); color: var(--secondary); padding: 2px 8px; border-radius: 4px; font-size: 12px; }

/* Experts */
.expert-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 30px; }
.expert-card { text-align: center; background: #fff; padding: 30px; border-radius: 12px; box-shadow: 0 5px 15px rgba(0,0,0,0.05); }
.expert-card img { width: 120px; height: 120px; border-radius: 50%; margin: 0 auto 20px; object-fit: cover; border: 3px solid var(--primary); }
.expert-name { font-size: 20px; font-weight: bold; margin-bottom: 5px; }
.expert-title { color: var(--primary); font-size: 14px; margin-bottom: 15px; }

/* FAQ & Comments */
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.faq-item { margin-bottom: 20px; border-bottom: 1px solid #eee; padding-bottom: 15px; }
.faq-q { font-weight: bold; font-size: 18px; margin-bottom: 10px; color: var(--dark); }
.faq-a { color: var(--gray); }
.comment-item { background: #fff; padding: 20px; border-radius: 8px; margin-bottom: 20px; box-shadow: 0 2px 10px rgba(0,0,0,0.05); }
.comment-user { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.comment-avatar { width: 40px; height: 40px; border-radius: 50%; background: var(--gradient); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: bold; }
.comment-name { font-weight: bold; }
.comment-date { color: #999; font-size: 12px; }
.stars { color: #FFD700; }

/* Footer */
footer { background: var(--dark); color: #fff; padding: 60px 0 20px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-col h3 { font-size: 18px; margin-bottom: 20px; color: var(--primary); }
.footer-links li { margin-bottom: 10px; }
.footer-links a { color: #aaa; transition: color 0.3s; }
.footer-links a:hover { color: #fff; }
.footer-qr { display: flex; gap: 20px; }
.qr-box { text-align: center; }
.qr-box div { width: 100px; height: 100px; background: #fff; margin-bottom: 10px; }
.footer-bottom { text-align: center; padding-top: 20px; border-top: 1px solid rgba(255,255,255,0.1); color: #888; font-size: 14px; }

/* Video Player Modal */
.modal { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.9); z-index: 1000; align-items: center; justify-content: center; }
.modal.active { display: flex; }
.modal-content { width: 90%; max-width: 1000px; position: relative; }
.close-btn { position: absolute; top: -40px; right: 0; color: #fff; font-size: 30px; cursor: pointer; }
.video-wrapper { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; background: #000; }
.video-wrapper iframe, .video-wrapper video { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }

@media (max-width: 768px) {
  .header-inner { flex-direction: column; height: auto; padding: 15px 0; gap: 15px; }
  .nav { flex-wrap: wrap; justify-content: center; }
  .hero h1 { font-size: 32px; }
  .two-col { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; text-align: center; }
  .footer-qr { justify-content: center; }
}