/* ============================================
   海角 - 汽车改装与视频社区 原创样式表
   配色方案：赛车红 #C41E3A + 碳纤维黑 #1B1B1B + 银灰 #E8E8E8
   ============================================ */
:root {
  --racing-red: #C41E3A;
  --racing-red-dark: #9A1830;
  --carbon: #1B1B1B;
  --carbon-light: #2D2D2D;
  --silver: #E8E8E8;
  --silver-dark: #B0B0B0;
  --asphalt: #3A3A3A;
  --white: #FFFFFF;
  --text-primary: #1B1B1B;
  --text-secondary: #5A5A5A;
  --text-light: #8A8A8A;
  --bg-main: #F5F5F5;
  --bg-card: #FFFFFF;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.16);
  --radius: 10px;
  --transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text-primary);
  background: var(--bg-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--racing-red); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--racing-red-dark); }
img { max-width: 100%; height: auto; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === Header & Navigation === */
.site-header {
  background: var(--carbon);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 12px rgba(0,0,0,0.3);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  max-width: 1200px;
  margin: 0 auto;
  height: 68px;
}
.site-logo { display: flex; align-items: center; gap: 10px; }
.site-logo img { height: 44px; width: auto; }
.site-logo span { color: var(--white); font-size: 1.3rem; font-weight: 700; letter-spacing: 1px; }
.main-nav { display: flex; gap: 4px; }
.main-nav a {
  color: var(--silver); font-size: 0.92rem; padding: 8px 14px;
  border-radius: 6px; transition: var(--transition); font-weight: 500;
}
.main-nav a:hover, .main-nav a.active { color: var(--white); background: var(--racing-red); }
.mobile-menu-btn { display: none; background: none; border: none; color: var(--white); font-size: 1.5rem; cursor: pointer; }

/* === Search Bar === */
.search-bar {
  background: var(--carbon-light);
  padding: 12px 0;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.search-bar form {
  display: flex; max-width: 600px; margin: 0 auto;
  background: var(--asphalt); border-radius: 30px; overflow: hidden;
  border: 1px solid rgba(255,255,255,0.1);
}
.search-bar input {
  flex: 1; padding: 10px 20px; background: transparent;
  border: none; color: var(--white); font-size: 0.9rem; outline: none;
}
.search-bar input::placeholder { color: var(--text-light); }
.search-bar button {
  padding: 10px 24px; background: var(--racing-red); color: var(--white);
  border: none; cursor: pointer; font-size: 0.9rem; font-weight: 600;
  transition: var(--transition);
}
.search-bar button:hover { background: var(--racing-red-dark); }

/* === Hero Section === */
.hero {
  position: relative; min-height: 520px; display: flex; align-items: center;
  background-size: cover; background-position: center; background-repeat: no-repeat;
  overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(27,27,27,0.85) 0%, rgba(196,30,58,0.4) 100%);
}
.hero-content {
  position: relative; z-index: 2; max-width: 700px; padding: 60px 20px;
  margin: 0 auto; text-align: center;
}
.hero h1 { color: var(--white); font-size: 2.6rem; font-weight: 800; margin-bottom: 16px; line-height: 1.3; }
.hero h1 em { font-style: normal; color: var(--racing-red); background: rgba(196,30,58,0.15); padding: 2px 8px; border-radius: 4px; }
.hero p { color: var(--silver); font-size: 1.1rem; margin-bottom: 28px; line-height: 1.8; }
.hero-btns { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn-primary {
  display: inline-block; padding: 12px 32px; background: var(--racing-red);
  color: var(--white); border-radius: 30px; font-weight: 600; font-size: 1rem;
  transition: var(--transition); border: 2px solid var(--racing-red);
}
.btn-primary:hover { background: var(--racing-red-dark); border-color: var(--racing-red-dark); color: var(--white); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-outline {
  display: inline-block; padding: 12px 32px; background: transparent;
  color: var(--white); border: 2px solid var(--silver); border-radius: 30px;
  font-weight: 600; font-size: 1rem; transition: var(--transition);
}
.btn-outline:hover { background: var(--white); color: var(--carbon); transform: translateY(-2px); }

/* === Section Common === */
.section { padding: 60px 0; }
.section-alt { background: var(--white); }
.section-dark { background: var(--carbon); color: var(--white); }
.section-title {
  text-align: center; font-size: 1.8rem; font-weight: 700;
  margin-bottom: 12px; color: var(--text-primary);
}
.section-dark .section-title { color: var(--white); }
.section-subtitle {
  text-align: center; color: var(--text-secondary); font-size: 1rem;
  margin-bottom: 40px; max-width: 600px; margin-left: auto; margin-right: auto;
}
.section-dark .section-subtitle { color: var(--silver-dark); }
.red-line {
  width: 60px; height: 4px; background: var(--racing-red);
  margin: 12px auto 20px; border-radius: 2px;
}

/* === Video Cards === */
.video-grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 20px; margin-top: 30px;
}
.video-card {
  background: var(--bg-card); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm);
  transition: var(--transition); position: relative;
}
.video-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.video-thumb {
  position: relative; overflow: hidden;
  aspect-ratio: 16/9;
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.4s ease; }
.video-card:hover .video-thumb img { transform: scale(1.08); }
.video-play {
  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 .video-play { opacity: 1; }
.video-play span {
  width: 56px; height: 56px; background: var(--racing-red); border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem; color: var(--white); box-shadow: 0 4px 16px rgba(196,30,58,0.4);
  transition: transform 0.3s ease;
}
.video-card:hover .video-play span { transform: scale(1.15); }
.video-duration {
  position: absolute; bottom: 8px; right: 8px;
  background: rgba(0,0,0,0.75); color: var(--white);
  padding: 2px 8px; border-radius: 4px; font-size: 0.78rem;
}
.video-info { padding: 14px; }
.video-title {
  font-size: 0.95rem; font-weight: 600; color: var(--text-primary);
  margin-bottom: 6px; line-height: 1.4;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.video-meta { display: flex; gap: 12px; font-size: 0.8rem; color: var(--text-light); }
.video-meta span { display: flex; align-items: center; gap: 3px; }

/* === Service Cards === */
.service-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.service-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 30px;
  box-shadow: var(--shadow-sm); transition: var(--transition);
  border-top: 4px solid transparent;
}
.service-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-top-color: var(--racing-red); }
.service-icon {
  width: 56px; height: 56px; background: linear-gradient(135deg, var(--racing-red), var(--racing-red-dark));
  border-radius: 12px; display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; color: var(--white); margin-bottom: 16px;
}
.service-card h4 { font-size: 1.1rem; margin-bottom: 10px; color: var(--carbon); }
.service-card p { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.7; }

/* === Expert Cards === */
.expert-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.expert-card {
  background: var(--bg-card); border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow-sm); text-align: center; transition: var(--transition);
}
.expert-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.expert-card img { width: 100%; aspect-ratio: 1; object-fit: cover; }
.expert-info { padding: 16px; }
.expert-name { font-size: 1.05rem; font-weight: 700; color: var(--carbon); margin-bottom: 4px; }
.expert-role { font-size: 0.82rem; color: var(--racing-red); margin-bottom: 8px; font-weight: 500; }
.expert-desc { font-size: 0.82rem; color: var(--text-secondary); line-height: 1.6; }
.expert-btns { display: flex; gap: 8px; justify-content: center; padding: 0 16px 16px; }
.expert-btns a {
  padding: 6px 14px; border-radius: 20px; font-size: 0.78rem; font-weight: 500;
  border: 1px solid var(--racing-red); color: var(--racing-red); transition: var(--transition);
}
.expert-btns a:hover { background: var(--racing-red); color: var(--white); }

/* === Community Features === */
.community-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.community-item {
  background: var(--carbon-light); border-radius: var(--radius); padding: 24px;
  text-align: center; transition: var(--transition);
}
.community-item:hover { background: var(--asphalt); transform: translateY(-3px); }
.community-item h5 { color: var(--white); font-size: 1rem; margin-bottom: 8px; }
.community-item p { color: var(--silver-dark); font-size: 0.85rem; }
.community-icon { font-size: 2rem; margin-bottom: 12px; }

/* === Stats === */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; text-align: center; }
.stat-item h4 { font-size: 2.2rem; font-weight: 800; color: var(--racing-red); margin-bottom: 4px; }
.stat-item p { font-size: 0.9rem; color: var(--text-secondary); }

/* === Reviews === */
.review-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.review-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 24px;
  box-shadow: var(--shadow-sm); border-left: 4px solid var(--racing-red);
}
.review-stars { color: #F5A623; font-size: 0.9rem; margin-bottom: 10px; }
.review-text { font-size: 0.92rem; color: var(--text-secondary); line-height: 1.7; margin-bottom: 12px; font-style: italic; }
.review-author { font-size: 0.85rem; color: var(--text-primary); font-weight: 600; }
.review-date { font-size: 0.78rem; color: var(--text-light); }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--bg-card); border-radius: var(--radius); margin-bottom: 12px;
  box-shadow: var(--shadow-sm); overflow: hidden;
}
.faq-question {
  padding: 18px 24px; font-weight: 600; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.95rem; transition: var(--transition);
}
.faq-question:hover { color: var(--racing-red); }
.faq-question::after { content: '+'; font-size: 1.3rem; color: var(--racing-red); transition: transform 0.3s; }
.faq-item.active .faq-question::after { transform: rotate(45deg); }
.faq-answer { padding: 0 24px 18px; font-size: 0.9rem; color: var(--text-secondary); line-height: 1.8; display: none; }
.faq-item.active .faq-answer { display: block; }

/* === How-To === */
.howto-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.howto-step {
  text-align: center; padding: 24px 16px;
  background: var(--bg-card); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); position: relative;
}
.howto-num {
  width: 44px; height: 44px; background: var(--racing-red); color: var(--white);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem; font-weight: 700; margin: 0 auto 14px;
}
.howto-step h4 { font-size: 1rem; margin-bottom: 8px; color: var(--carbon); }
.howto-step p { font-size: 0.85rem; color: var(--text-secondary); }

/* === Contact === */
.contact-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }
.contact-info { padding: 30px; background: var(--bg-card); border-radius: var(--radius); box-shadow: var(--shadow-sm); }
.contact-info h3 { font-size: 1.2rem; margin-bottom: 16px; color: var(--carbon); }
.contact-item { display: flex; gap: 12px; margin-bottom: 14px; font-size: 0.9rem; color: var(--text-secondary); }
.contact-item strong { color: var(--text-primary); min-width: 70px; }
.qrcode-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.qrcode-item { text-align: center; }
.qrcode-item img { width: 140px; height: 140px; margin: 0 auto 8px; border-radius: 8px; }
.qrcode-item p { font-size: 0.82rem; color: var(--text-secondary); }

/* === Share === */
.share-section { text-align: center; padding: 30px 0; }
.share-btns { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-top: 16px; }
.share-btn {
  padding: 10px 20px; border-radius: 25px; font-size: 0.85rem;
  font-weight: 500; transition: var(--transition); cursor: pointer; border: none;
}
.share-wechat { background: #07C160; color: var(--white); }
.share-weibo { background: #E6162D; color: var(--white); }
.share-douyin { background: #161823; color: var(--white); }
.share-bilibili { background: #00A1D6; color: var(--white); }
.share-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); opacity: 0.9; }

/* === Breadcrumb === */
.breadcrumb {
  padding: 14px 0; font-size: 0.82rem; color: var(--text-light);
  border-bottom: 1px solid var(--silver);
}
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--racing-red); }
.breadcrumb span { margin: 0 6px; }

/* === Brand Wall === */
.brand-wall { display: flex; gap: 30px; justify-content: center; flex-wrap: wrap; align-items: center; opacity: 0.6; }
.brand-wall span { font-size: 1.1rem; font-weight: 600; color: var(--text-light); letter-spacing: 2px; }

/* === Footer === */
.site-footer { background: var(--carbon); color: var(--silver-dark); padding: 50px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 30px; margin-bottom: 30px; }
.footer-brand img { height: 40px; margin-bottom: 12px; }
.footer-brand p { font-size: 0.85rem; line-height: 1.7; color: var(--silver-dark); }
.footer-col h4 { color: var(--white); font-size: 1rem; margin-bottom: 14px; }
.footer-col a { display: block; color: var(--silver-dark); font-size: 0.85rem; margin-bottom: 8px; transition: var(--transition); }
.footer-col a:hover { color: var(--racing-red); }
.footer-bottom {
  border-top: 1px solid var(--asphalt); padding: 20px 0;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.82rem; flex-wrap: wrap; gap: 10px;
}
.footer-bottom a { color: var(--silver-dark); }

/* === Article Content === */
.article-content { max-width: 900px; margin: 0 auto; }
.article-content p { margin-bottom: 18px; font-size: 0.95rem; line-height: 1.9; color: var(--text-secondary); }
.article-content h3 { font-size: 1.2rem; margin: 28px 0 12px; color: var(--carbon); }

/* === Honor === */
.honor-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
.honor-item {
  background: var(--bg-card); border-radius: var(--radius); padding: 24px 16px;
  box-shadow: var(--shadow-sm); transition: var(--transition);
}
.honor-item:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.honor-icon { font-size: 2.2rem; margin-bottom: 10px; }
.honor-item h4 { font-size: 0.95rem; margin-bottom: 6px; color: var(--carbon); }
.honor-item p { font-size: 0.8rem; color: var(--text-light); }

/* === Industry Insight === */
.insight-card {
  background: var(--bg-card); border-radius: var(--radius); padding: 30px;
  box-shadow: var(--shadow-sm); max-width: 900px; margin: 0 auto;
}
.insight-card h3 { font-size: 1.15rem; color: var(--carbon); margin-bottom: 14px; }
.insight-card p { font-size: 0.92rem; color: var(--text-secondary); line-height: 1.8; margin-bottom: 12px; }

/* === Responsive === */
@media (max-width: 1024px) {
  .video-grid { grid-template-columns: repeat(3, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .honor-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .header-inner { height: 56px; }
  .main-nav { display: none; flex-direction: column; position: absolute; top: 56px; left: 0; right: 0; background: var(--carbon); padding: 16px; gap: 4px; z-index: 999; }
  .main-nav.show { display: flex; }
  .mobile-menu-btn { display: block; }
  .hero { min-height: 400px; }
  .hero h1 { font-size: 1.8rem; }
  .video-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .service-grid { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: repeat(2, 1fr); }
  .review-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .howto-grid { grid-template-columns: repeat(2, 1fr); }
  .section-title { font-size: 1.4rem; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
}
@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: 1fr; }
  .howto-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .honor-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 1.5rem; }
  .hero-btns { flex-direction: column; align-items: center; }
}