/* Reset & Base */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif; line-height: 1.6; color: #333; background-color: #f4f4f4; }
a { text-decoration: none; color: inherit; transition: color 0.3s ease; }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

/* Typography */
h1, h2, h3, h4, h5, h6 { font-weight: 700; color: #111; margin-bottom: 1rem; }
.brand-text { color: #e60000; font-weight: 900; }
.section-title { text-align: center; font-size: 2.5rem; margin-bottom: 3rem; text-transform: uppercase; letter-spacing: 2px; }
.section-title::after { content: ''; display: block; width: 60px; height: 4px; background: #e60000; margin: 10px auto 0; }

/* Layout */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 5rem 0; background: #fff; }
.section-dark { background: #1a1a1a; color: #fff; }
.section-dark h2, .section-dark h3 { color: #fff; }

/* Header & Nav */
.header { background: rgba(0,0,0,0.9); position: fixed; width: 100%; top: 0; z-index: 1000; padding: 15px 0; border-bottom: 2px solid #e60000; }
.header-inner { display: flex; justify-content: space-between; align-items: center; }
.logo img { height: 50px; }
.nav ul { display: flex; gap: 20px; }
.nav a { color: #fff; font-weight: 600; font-size: 1.1rem; padding: 5px 10px; }
.nav a:hover { color: #e60000; }
.search-box { display: flex; align-items: center; background: #333; border-radius: 20px; padding: 5px 15px; margin-left: 20px; }
.search-box input { background: transparent; border: none; color: #fff; outline: none; padding: 5px; }
.search-box button { background: transparent; border: none; color: #e60000; cursor: pointer; }

/* Hero Banner */
.hero { height: 100vh; background: url('../images/banner.jpg') no-repeat center center/cover; position: relative; display: flex; align-items: center; }
.hero::before { content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.6); }
.hero-content { position: relative; z-index: 1; color: #fff; max-width: 800px; padding-top: 80px; }
.hero h1 { font-size: 4rem; margin-bottom: 1rem; text-shadow: 2px 2px 4px rgba(0,0,0,0.5); color: #fff; }
.hero p { font-size: 1.5rem; margin-bottom: 2rem; }
.btn { display: inline-block; padding: 12px 30px; background: #e60000; color: #fff; font-weight: bold; border-radius: 30px; text-transform: uppercase; letter-spacing: 1px; transition: transform 0.3s ease, box-shadow 0.3s ease; }
.btn:hover { transform: translateY(-3px); box-shadow: 0 10px 20px rgba(230,0,0,0.4); color: #fff; }

/* Breadcrumb */
.breadcrumb { padding: 100px 0 20px; background: #f4f4f4; border-bottom: 1px solid #ddd; }
.breadcrumb a { color: #e60000; }

/* Video Cards */
.video-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.video-card { background: #fff; border-radius: 10px; overflow: hidden; box-shadow: 0 5px 15px rgba(0,0,0,0.1); transition: transform 0.3s ease; position: relative; }
.video-card:hover { transform: translateY(-10px); }
.video-thumb { position: relative; cursor: pointer; }
.video-thumb img { width: 100%; height: 200px; object-fit: cover; }
.play-btn { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); width: 60px; height: 60px; background: rgba(230,0,0,0.8); border-radius: 50%; display: flex; justify-content: center; align-items: center; opacity: 0; transition: opacity 0.3s ease; }
.play-btn::after { content: ''; width: 0; height: 0; border-style: solid; border-width: 10px 0 10px 20px; border-color: transparent transparent transparent #fff; margin-left: 5px; }
.video-thumb:hover .play-btn { opacity: 1; }
.video-info { padding: 20px; }
.video-title { font-size: 1.2rem; margin-bottom: 10px; }
.video-meta { display: flex; justify-content: space-between; color: #777; font-size: 0.9rem; }

/* Features / AI */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.feature-card { text-align: center; padding: 40px 20px; background: #f9f9f9; border-radius: 10px; border-bottom: 4px solid #e60000; }
.feature-icon { font-size: 3rem; color: #e60000; margin-bottom: 20px; }

/* Experts */
.expert-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.expert-card { text-align: center; background: #fff; padding: 30px; border-radius: 10px; box-shadow: 0 5px 15px rgba(0,0,0,0.1); }
.expert-img { width: 150px; height: 150px; border-radius: 50%; margin: 0 auto 20px; overflow: hidden; border: 4px solid #e60000; }
.expert-img img { width: 100%; height: 100%; object-fit: cover; }
.expert-title { color: #e60000; font-weight: bold; margin-bottom: 15px; }

/* FAQ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { background: #fff; margin-bottom: 15px; border-radius: 5px; box-shadow: 0 2px 5px rgba(0,0,0,0.05); }
.faq-q { padding: 20px; font-weight: bold; cursor: pointer; position: relative; border-left: 4px solid #e60000; }
.faq-q::after { content: '+'; position: absolute; right: 20px; top: 50%; transform: translateY(-50%); font-size: 1.5rem; color: #e60000; }
.faq-a { padding: 0 20px 20px; display: none; color: #666; }

/* Reviews */
.review-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }
.review-card { background: #f9f9f9; padding: 30px; border-radius: 10px; position: relative; }
.review-card::before { content: '"'; font-size: 4rem; color: #e60000; opacity: 0.2; position: absolute; top: 10px; left: 20px; font-family: serif; }
.review-text { font-style: italic; margin-bottom: 20px; position: relative; z-index: 1; }
.review-author { font-weight: bold; color: #e60000; }

/* Footer */
.footer { background: #111; color: #fff; padding: 60px 0 20px; }
.footer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; margin-bottom: 40px; }
.footer-title { color: #e60000; margin-bottom: 20px; font-size: 1.2rem; }
.footer-links li { margin-bottom: 10px; }
.footer-links a:hover { color: #e60000; padding-left: 5px; }
.qrcode-box { display: flex; gap: 15px; }
.qrcode { text-align: center; }
.qrcode img { width: 100px; height: 100px; background: #fff; padding: 5px; margin-bottom: 5px; }
.footer-bottom { text-align: center; padding-top: 20px; border-top: 1px solid #333; font-size: 0.9rem; color: #888; }

/* Responsive */
@media (max-width: 992px) {
    .features, .expert-grid { grid-template-columns: repeat(2, 1fr); }
    .review-grid, .footer-grid { grid-template-columns: 1fr; }
    .hero h1 { font-size: 3rem; }
}
@media (max-width: 768px) {
    .header-inner { flex-direction: column; gap: 15px; }
    .nav ul { flex-wrap: wrap; justify-content: center; }
    .video-grid { grid-template-columns: 1fr; }
    .features, .expert-grid { grid-template-columns: 1fr; }
}