/* ============================================================
   51吃瓜视频网 - 主样式文件
   Brand: 51吃瓜视频网 | Domain: 891163.cn
   ============================================================ */

/* ---------- CSS Variables ---------- */
:root {
  --primary: #e8192c;
  --primary-dark: #b5101e;
  --primary-light: #ff4d5e;
  --secondary: #1a1a2e;
  --accent: #ff6b35;
  --accent2: #4ecdc4;
  --bg-dark: #0f0f1a;
  --bg-card: #1c1c2e;
  --bg-light: #f8f9fa;
  --text-main: #1a1a2e;
  --text-muted: #6c757d;
  --text-white: #ffffff;
  --border: #e0e0e0;
  --shadow: 0 4px 20px rgba(0,0,0,0.12);
  --shadow-hover: 0 8px 32px rgba(232,25,44,0.18);
  --radius: 12px;
  --radius-sm: 6px;
  --transition: all 0.3s ease;
  --font-main: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
}

/* ---------- Reset & Base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-main);
  color: var(--text-main);
  background: #fff;
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: var(--font-main); }

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-main);
}
h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.4rem); }
h4 { font-size: 1.1rem; }
p { margin-bottom: 1rem; }

/* ---------- Layout Utilities ---------- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.container-wide { max-width: 1400px; margin: 0 auto; padding: 0 20px; }
.section { padding: 60px 0; }
.section-alt { background: var(--bg-light); }
.section-dark { background: var(--secondary); color: var(--text-white); }
.section-dark h2, .section-dark h3, .section-dark h4 { color: var(--text-white); }
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.text-center { text-align: center; }
.text-red { color: var(--primary); }
.mt-1 { margin-top: 8px; } .mt-2 { margin-top: 16px; } .mt-3 { margin-top: 24px; } .mt-4 { margin-top: 32px; }
.mb-1 { margin-bottom: 8px; } .mb-2 { margin-bottom: 16px; } .mb-3 { margin-bottom: 24px; }
.hidden { display: none !important; }

/* ---------- Section Header ---------- */
.section-header { text-align: center; margin-bottom: 40px; }
.section-header h2 { position: relative; display: inline-block; padding-bottom: 14px; }
.section-header h2::after {
  content: '';
  position: absolute;
  bottom: 0; left: 50%;
  transform: translateX(-50%);
  width: 60px; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
}
.section-header p { color: var(--text-muted); font-size: 1.05rem; margin-top: 12px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 10px 24px; border-radius: 50px;
  font-size: 0.95rem; font-weight: 600;
  transition: var(--transition); cursor: pointer;
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  box-shadow: 0 4px 15px rgba(232,25,44,0.3);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(232,25,44,0.45);
  color: #fff;
}
.btn-outline {
  border: 2px solid var(--primary);
  color: var(--primary);
  background: transparent;
}
.btn-outline:hover { background: var(--primary); color: #fff; }
.btn-white { background: #fff; color: var(--primary); font-weight: 700; }
.btn-white:hover { background: var(--primary); color: #fff; }
.btn-sm { padding: 6px 16px; font-size: 0.85rem; }
.btn-lg { padding: 14px 36px; font-size: 1.05rem; }

/* ---------- Header / Navigation ---------- */
#site-header {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(15,15,26,0.97);
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.3);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; padding: 0 20px; max-width: 1200px; margin: 0 auto;
}
.site-logo { display: flex; align-items: center; gap: 10px; }
.site-logo img { width: 44px; height: 44px; border-radius: 8px; object-fit: cover; }
.site-logo .logo-text {
  font-size: 1.2rem; font-weight: 800;
  background: linear-gradient(135deg, #fff, var(--primary-light));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  color: rgba(255,255,255,0.85); padding: 8px 14px;
  border-radius: var(--radius-sm); font-size: 0.9rem; font-weight: 500;
  transition: var(--transition);
}
.main-nav a:hover, .main-nav a.active {
  color: #fff; background: rgba(232,25,44,0.2);
}
.nav-cta { background: var(--primary) !important; color: #fff !important; border-radius: 50px !important; }
.nav-cta:hover { background: var(--primary-dark) !important; }
.hamburger { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.hamburger span { display: block; width: 24px; height: 2px; background: #fff; border-radius: 2px; transition: var(--transition); }

/* ---------- Search Bar ---------- */
.search-bar-wrap {
  background: linear-gradient(135deg, #1a1a2e, #16213e);
  padding: 12px 0;
  border-bottom: 1px solid rgba(255,255,255,0.05);
}
.search-bar-inner {
  max-width: 700px; margin: 0 auto; padding: 0 20px;
  display: flex; gap: 0;
}
.search-input {
  flex: 1; padding: 10px 18px;
  border: 2px solid rgba(255,255,255,0.1);
  border-right: none;
  border-radius: 50px 0 0 50px;
  background: rgba(255,255,255,0.08);
  color: #fff; font-size: 0.95rem;
  outline: none; font-family: var(--font-main);
  transition: var(--transition);
}
.search-input::placeholder { color: rgba(255,255,255,0.4); }
.search-input:focus { border-color: var(--primary); background: rgba(255,255,255,0.12); }
.search-btn {
  padding: 10px 22px;
  background: var(--primary);
  color: #fff; font-size: 0.95rem; font-weight: 600;
  border-radius: 0 50px 50px 0;
  transition: var(--transition);
}
.search-btn:hover { background: var(--primary-dark); }
.search-hot { max-width: 700px; margin: 6px auto 0; padding: 0 20px; display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.search-hot span { color: rgba(255,255,255,0.5); font-size: 0.8rem; }
.search-hot a { color: rgba(255,255,255,0.7); font-size: 0.8rem; padding: 2px 10px; border-radius: 50px; background: rgba(255,255,255,0.08); }
.search-hot a:hover { background: var(--primary); color: #fff; }

/* ---------- Hero Banner ---------- */
.hero {
  position: relative; min-height: 520px;
  display: flex; align-items: center;
  background: linear-gradient(135deg, #0f0f1a 0%, #1a1a2e 50%, #16213e 100%);
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background-image: url('../images/hero-banner.jpg');
  background-size: cover; background-position: center;
  opacity: 0.25;
}
.hero-content { position: relative; z-index: 2; max-width: 640px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 6px;
  background: rgba(232,25,44,0.15); border: 1px solid rgba(232,25,44,0.4);
  color: var(--primary-light); padding: 4px 14px; border-radius: 50px;
  font-size: 0.82rem; font-weight: 600; margin-bottom: 16px;
}
.hero h1 { color: #fff; margin-bottom: 16px; }
.hero h1 span { color: var(--primary-light); }
.hero p { color: rgba(255,255,255,0.75); font-size: 1.05rem; margin-bottom: 28px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 32px; margin-top: 40px; }
.hero-stat { text-align: center; }
.hero-stat .num { font-size: 1.8rem; font-weight: 800; color: var(--primary-light); line-height: 1; }
.hero-stat .label { font-size: 0.8rem; color: rgba(255,255,255,0.55); margin-top: 4px; }

/* ---------- Video Cards ---------- */
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 20px; }
.video-card {
  background: #fff; border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden;
  transition: var(--transition); cursor: pointer;
}
.video-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
.video-thumb {
  position: relative; overflow: hidden;
  aspect-ratio: 16/9; background: #1a1a2e;
}
.video-thumb img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }
.play-btn {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.35);
  opacity: 0; transition: var(--transition);
}
.video-card:hover .play-btn { opacity: 1; }
.play-btn svg {
  width: 52px; height: 52px;
  filter: drop-shadow(0 2px 8px rgba(0,0,0,0.5));
  transition: transform 0.2s;
}
.video-card:hover .play-btn svg { transform: scale(1.1); }
.video-duration {
  position: absolute; bottom: 8px; right: 8px;
  background: rgba(0,0,0,0.75); color: #fff;
  font-size: 0.75rem; padding: 2px 7px; border-radius: 4px;
}
.video-tag {
  position: absolute; top: 8px; left: 8px;
  background: var(--primary); color: #fff;
  font-size: 0.72rem; padding: 2px 8px; border-radius: 4px; font-weight: 600;
}
.video-info { padding: 14px; }
.video-info h3 { font-size: 0.95rem; font-weight: 600; margin-bottom: 8px; line-height: 1.4; }
.video-info h3 a { color: var(--text-main); }
.video-info h3 a:hover { color: var(--primary); }
.video-meta { display: flex; align-items: center; justify-content: space-between; }
.video-stats { display: flex; gap: 12px; }
.video-stats span { display: flex; align-items: center; gap: 4px; font-size: 0.8rem; color: var(--text-muted); }
.video-author { display: flex; align-items: center; gap: 6px; }
.video-author img { width: 24px; height: 24px; border-radius: 50%; object-fit: cover; }
.video-author span { font-size: 0.8rem; color: var(--text-muted); }

/* ---------- Category Tabs ---------- */
.cat-tabs { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 28px; }
.cat-tab {
  padding: 7px 18px; border-radius: 50px;
  border: 1.5px solid var(--border);
  font-size: 0.88rem; font-weight: 500; color: var(--text-muted);
  transition: var(--transition); cursor: pointer; background: #fff;
}
.cat-tab:hover, .cat-tab.active {
  background: var(--primary); border-color: var(--primary); color: #fff;
}

/* ---------- Feature Cards ---------- */
.feature-card {
  background: #fff; border-radius: var(--radius);
  padding: 28px 24px; box-shadow: var(--shadow);
  transition: var(--transition); text-align: center;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
.feature-icon {
  width: 60px; height: 60px; border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 16px; font-size: 1.6rem;
}
.feature-icon.red { background: rgba(232,25,44,0.1); }
.feature-icon.blue { background: rgba(78,205,196,0.1); }
.feature-icon.orange { background: rgba(255,107,53,0.1); }
.feature-icon.purple { background: rgba(155,89,182,0.1); }
.feature-card h3 { font-size: 1.05rem; margin-bottom: 8px; }
.feature-card p { font-size: 0.9rem; color: var(--text-muted); margin: 0; }

/* ---------- Expert Cards ---------- */
.expert-card {
  background: #fff; border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
  transition: var(--transition);
}
.expert-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
.expert-img { position: relative; height: 220px; overflow: hidden; }
.expert-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.4s; }
.expert-card:hover .expert-img img { transform: scale(1.05); }
.expert-badge {
  position: absolute; top: 12px; right: 12px;
  background: var(--primary); color: #fff;
  font-size: 0.75rem; padding: 3px 10px; border-radius: 50px;
}
.expert-info { padding: 18px; }
.expert-info h3 { font-size: 1rem; margin-bottom: 4px; }
.expert-role { font-size: 0.82rem; color: var(--primary); font-weight: 600; margin-bottom: 8px; }
.expert-desc { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 12px; line-height: 1.5; }
.expert-awards { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 12px; }
.expert-awards span { font-size: 0.75rem; background: var(--bg-light); padding: 2px 8px; border-radius: 4px; color: var(--text-muted); }
.expert-actions { display: flex; gap: 8px; }

/* ---------- Reviews ---------- */
.review-card {
  background: #fff; border-radius: var(--radius);
  padding: 24px; box-shadow: var(--shadow);
}
.review-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.review-avatar { width: 44px; height: 44px; border-radius: 50%; background: linear-gradient(135deg, var(--primary), var(--accent)); display: flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; font-size: 1rem; flex-shrink: 0; }
.review-meta h4 { font-size: 0.95rem; margin-bottom: 2px; }
.review-meta span { font-size: 0.8rem; color: var(--text-muted); }
.stars { color: #f5a623; font-size: 0.9rem; margin-bottom: 8px; }
.review-text { font-size: 0.9rem; color: #444; line-height: 1.6; }
.review-platform { font-size: 0.78rem; color: var(--text-muted); margin-top: 10px; }

/* ---------- FAQ ---------- */
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 12px; overflow: hidden; }
.faq-q {
  padding: 16px 20px; font-weight: 600; font-size: 0.95rem;
  cursor: pointer; display: flex; justify-content: space-between; align-items: center;
  background: #fff; transition: var(--transition);
}
.faq-q:hover { background: var(--bg-light); }
.faq-q.open { background: rgba(232,25,44,0.04); color: var(--primary); }
.faq-icon { font-size: 1.2rem; transition: transform 0.3s; }
.faq-q.open .faq-icon { transform: rotate(45deg); }
.faq-a { padding: 0 20px; max-height: 0; overflow: hidden; transition: max-height 0.35s ease, padding 0.2s; }
.faq-a.open { max-height: 300px; padding: 0 20px 16px; }
.faq-a p { font-size: 0.9rem; color: var(--text-muted); margin: 0; }

/* ---------- Partner Logos ---------- */
.partner-grid { display: flex; flex-wrap: wrap; gap: 16px; justify-content: center; align-items: center; }
.partner-logo {
  background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 14px 24px;
  font-size: 0.9rem; font-weight: 600; color: var(--text-muted);
  transition: var(--transition);
}
.partner-logo:hover { border-color: var(--primary); color: var(--primary); box-shadow: var(--shadow); }

/* ---------- Stats Bar ---------- */
.stats-bar { background: linear-gradient(135deg, var(--primary), var(--accent)); padding: 32px 0; }
.stats-bar .container { display: flex; justify-content: space-around; flex-wrap: wrap; gap: 20px; }
.stat-item { text-align: center; color: #fff; }
.stat-item .num { font-size: 2rem; font-weight: 800; line-height: 1; }
.stat-item .label { font-size: 0.85rem; opacity: 0.85; margin-top: 4px; }

/* ---------- Contact Section ---------- */
.contact-card {
  background: #fff; border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow);
}
.contact-item { display: flex; gap: 14px; margin-bottom: 20px; align-items: flex-start; }
.contact-icon { width: 44px; height: 44px; border-radius: 10px; background: rgba(232,25,44,0.1); display: flex; align-items: center; justify-content: center; font-size: 1.2rem; flex-shrink: 0; }
.contact-text h4 { font-size: 0.9rem; color: var(--text-muted); margin-bottom: 2px; }
.contact-text p { font-size: 0.95rem; font-weight: 600; margin: 0; }
.qr-grid { display: flex; gap: 20px; flex-wrap: wrap; }
.qr-item { text-align: center; }
.qr-item img { width: 120px; height: 120px; border-radius: 8px; border: 2px solid var(--border); }
.qr-item p { font-size: 0.8rem; color: var(--text-muted); margin-top: 6px; }

/* ---------- Social Share ---------- */
.share-bar { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.share-label { font-size: 0.88rem; color: var(--text-muted); }
.share-btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 7px 16px; border-radius: 50px;
  font-size: 0.82rem; font-weight: 600; color: #fff;
  transition: var(--transition);
}
.share-btn:hover { transform: translateY(-2px); opacity: 0.9; color: #fff; }
.share-wechat { background: #07c160; }
.share-weibo { background: #e6162d; }
.share-douyin { background: #010101; }
.share-bilibili { background: #00a1d6; }

/* ---------- Breadcrumb ---------- */
.breadcrumb { padding: 12px 0; font-size: 0.85rem; color: var(--text-muted); }
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb span { margin: 0 6px; }

/* ---------- Footer ---------- */
#site-footer { background: var(--bg-dark); color: rgba(255,255,255,0.7); padding: 48px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .logo-text { font-size: 1.3rem; font-weight: 800; color: #fff; display: block; margin-bottom: 12px; }
.footer-brand p { font-size: 0.88rem; line-height: 1.7; margin-bottom: 16px; }
.footer-col h4 { color: #fff; font-size: 0.95rem; margin-bottom: 16px; padding-bottom: 8px; border-bottom: 1px solid rgba(255,255,255,0.1); }
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { color: rgba(255,255,255,0.6); font-size: 0.88rem; transition: var(--transition); }
.footer-col ul li a:hover { color: var(--primary-light); padding-left: 4px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 20px 0; display: flex;
  justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 12px;
}
.footer-bottom p { font-size: 0.82rem; color: rgba(255,255,255,0.45); margin: 0; }
.footer-links { display: flex; gap: 16px; }
.footer-links a { font-size: 0.82rem; color: rgba(255,255,255,0.45); }
.footer-links a:hover { color: var(--primary-light); }
.footer-qr { display: flex; gap: 20px; margin-top: 16px; }
.footer-qr-item { text-align: center; }
.footer-qr-item img { width: 80px; height: 80px; border-radius: 6px; }
.footer-qr-item span { display: block; font-size: 0.72rem; color: rgba(255,255,255,0.45); margin-top: 4px; }

/* ---------- Page Hero (Inner Pages) ---------- */
.page-hero {
  background: linear-gradient(135deg, var(--secondary), #16213e);
  padding: 48px 0 40px; color: #fff;
}
.page-hero h1 { color: #fff; margin-bottom: 8px; }
.page-hero p { color: rgba(255,255,255,0.7); margin: 0; }

/* ---------- Tag Badges ---------- */
.tag { display: inline-block; padding: 3px 10px; border-radius: 4px; font-size: 0.78rem; font-weight: 600; }
.tag-red { background: rgba(232,25,44,0.1); color: var(--primary); }
.tag-blue { background: rgba(78,205,196,0.1); color: var(--accent2); }
.tag-orange { background: rgba(255,107,53,0.1); color: var(--accent); }
.tag-gray { background: var(--bg-light); color: var(--text-muted); }

/* ---------- How-To Steps ---------- */
.steps-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 24px; }
.step-card { text-align: center; padding: 28px 20px; }
.step-num {
  width: 52px; height: 52px; border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; font-size: 1.3rem; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 16px;
}
.step-card h3 { font-size: 1rem; margin-bottom: 8px; }
.step-card p { font-size: 0.88rem; color: var(--text-muted); margin: 0; }

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: #f1f1f1; }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 3px; }

/* ---------- Animations ---------- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-in { animation: fadeInUp 0.5s ease forwards; }

/* ---------- Mobile Nav ---------- */
.mobile-nav {
  display: none; position: fixed; inset: 0; z-index: 999;
  background: rgba(15,15,26,0.98); flex-direction: column;
  align-items: center; justify-content: center; gap: 20px;
}
.mobile-nav.open { display: flex; }
.mobile-nav a { color: #fff; font-size: 1.2rem; font-weight: 600; }
.mobile-nav a:hover { color: var(--primary-light); }
.mobile-close { position: absolute; top: 20px; right: 20px; color: #fff; font-size: 1.5rem; }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .section { padding: 40px 0; }
  .main-nav { display: none; }
  .hamburger { display: flex; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .hero { min-height: 400px; }
  .hero-stats { gap: 20px; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .stats-bar .container { gap: 24px; }
  .stat-item .num { font-size: 1.5rem; }
}
@media (max-width: 480px) {
  .hero h1 { font-size: 1.5rem; }
  .btn-lg { padding: 11px 24px; font-size: 0.95rem; }
  .video-grid { grid-template-columns: 1fr; }
}