/* ============================================
   兄妹乱伦 修车改装视频社区 - 全站样式表
   品牌色系：赛车红 #E8350F / 深夜蓝黑 #1A1A2E / 改装橙 #FF6B35
   ============================================ */

/* --- CSS Reset & Base --- */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;background:#0D0D1A;color:#F0F0F5;line-height:1.7;overflow-x:hidden}
a{color:#FF6B35;text-decoration:none;transition:color .3s}
a:hover{color:#E8350F}
img{max-width:100%;height:auto;display:block}
ul,ol{list-style:none}
h1,h2,h3,h4,h5,h6{font-weight:700;line-height:1.3;color:#F0F0F5}

/* --- Container --- */
.container{max-width:1280px;margin:0 auto;padding:0 20px}
.section-padding{padding:70px 0}

/* --- Header / Navigation --- */
.site-header{position:fixed;top:0;left:0;width:100%;z-index:1000;background:rgba(13,13,26,.92);backdrop-filter:blur(12px);border-bottom:1px solid rgba(232,53,15,.15);transition:background .3s}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo-wrap{display:flex;align-items:center;gap:10px}
.logo-wrap img{height:42px;width:auto}
.logo-wrap span{font-size:22px;font-weight:800;color:#E8350F;letter-spacing:2px}
.main-nav{display:flex;align-items:center;gap:6px}
.main-nav a{padding:8px 16px;font-size:15px;color:#9A9AB0;border-radius:6px;transition:all .3s;font-weight:500}
.main-nav a:hover,.main-nav a.active{color:#F0F0F5;background:rgba(232,53,15,.12)}

/* --- Search Box --- */
.search-bar{position:relative;margin-left:16px}
.search-bar input{width:200px;height:36px;padding:0 36px 0 14px;border:1px solid rgba(154,154,176,.3);border-radius:20px;background:rgba(22,22,42,.8);color:#F0F0F5;font-size:14px;outline:none;transition:all .3s}
.search-bar input:focus{border-color:#E8350F;width:260px}
.search-bar input::placeholder{color:#9A9AB0}
.search-bar button{position:absolute;right:4px;top:50%;transform:translateY(-50%);width:28px;height:28px;border:none;background:transparent;color:#9A9AB0;cursor:pointer;font-size:16px}
.search-bar button:hover{color:#E8350F}

/* --- Mobile Menu Toggle --- */
.menu-toggle{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:8px}
.menu-toggle span{display:block;width:24px;height:2px;background:#F0F0F5;border-radius:2px;transition:all .3s}

/* --- Banner / Hero --- */
.hero-banner{position:relative;width:100%;min-height:560px;display:flex;align-items:center;justify-content:center;overflow:hidden;margin-top:68px}
.hero-banner .hero-bg{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;filter:brightness(.45)}
.hero-overlay{position:absolute;top:0;left:0;width:100%;height:100%;background:linear-gradient(180deg,rgba(13,13,26,.3) 0%,rgba(13,13,26,.85) 100%)}
.hero-content{position:relative;z-index:2;text-align:center;max-width:800px;padding:40px 20px}
.hero-content h1{font-size:48px;margin-bottom:16px;background:linear-gradient(135deg,#E8350F,#FF6B35);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero-content .hero-sub{font-size:20px;color:#9A9AB0;margin-bottom:24px;line-height:1.6}
.hero-content .hero-tags{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-bottom:28px}
.hero-content .hero-tags span{padding:6px 16px;border:1px solid rgba(232,53,15,.4);border-radius:20px;font-size:13px;color:#FF6B35;background:rgba(232,53,15,.08)}
.hero-btn{display:inline-block;padding:14px 40px;background:linear-gradient(135deg,#E8350F,#FF6B35);color:#fff;font-size:16px;font-weight:600;border-radius:30px;border:none;cursor:pointer;transition:transform .3s,box-shadow .3s}
.hero-btn:hover{transform:translateY(-2px);box-shadow:0 8px 30px rgba(232,53,15,.4);color:#fff}

/* --- Section Titles --- */
.section-title{text-align:center;margin-bottom:50px}
.section-title h2{font-size:36px;margin-bottom:12px;position:relative;display:inline-block}
.section-title h2::after{content:"";display:block;width:60px;height:3px;background:linear-gradient(90deg,#E8350F,#FF6B35);margin:12px auto 0;border-radius:2px}
.section-title p{color:#9A9AB0;font-size:16px;margin-top:10px}

/* --- Video Card Grid --- */
.video-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:24px}
.video-card{position:relative;border-radius:12px;overflow:hidden;background:#16162A;transition:transform .3s,box-shadow .3s;cursor:pointer}
.video-card:hover{transform:translateY(-6px);box-shadow:0 12px 40px rgba(232,53,15,.2)}
.video-card .thumb{position:relative;width:100%;padding-top:56.25%;overflow:hidden}
.video-card .thumb img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;transition:transform .4s}
.video-card:hover .thumb img{transform:scale(1.06)}
.video-card .play-btn{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%) scale(0);width:60px;height:60px;background:rgba(232,53,15,.85);border-radius:50%;display:flex;align-items:center;justify-content:center;transition:transform .3s;z-index:3}
.video-card:hover .play-btn{transform:translate(-50%,-50%) scale(1)}
.play-btn::after{content:"";display:block;width:0;height:0;border-left:20px solid #fff;border-top:12px solid transparent;border-bottom:12px solid transparent;margin-left:4px}
.video-card .card-info{padding:16px}
.video-card .card-info h3{font-size:16px;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-card .card-meta{display:flex;align-items:center;gap:16px;font-size:13px;color:#9A9AB0}
.video-card .card-meta span{display:flex;align-items:center;gap:4px}
.video-card .card-tags{display:flex;gap:6px;margin-top:10px;flex-wrap:wrap}
.video-card .card-tags span{font-size:11px;padding:3px 10px;background:rgba(232,53,15,.1);color:#FF6B35;border-radius:12px}
.video-card .duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,.75);color:#fff;padding:2px 8px;border-radius:4px;font-size:12px;z-index:2}

/* --- Feature Grid (3 columns) --- */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.feature-card{background:#16162A;border-radius:14px;padding:36px 28px;text-align:center;border:1px solid rgba(154,154,176,.08);transition:all .3s}
.feature-card:hover{border-color:rgba(232,53,15,.3);box-shadow:0 8px 30px rgba(232,53,15,.1)}
.feature-card .icon{width:64px;height:64px;margin:0 auto 20px;background:linear-gradient(135deg,rgba(232,53,15,.15),rgba(255,107,53,.15));border-radius:16px;display:flex;align-items:center;justify-content:center;font-size:28px}
.feature-card h3{font-size:20px;margin-bottom:12px}
.feature-card p{color:#9A9AB0;font-size:14px;line-height:1.7}

/* --- AI Section --- */
.ai-section{position:relative;overflow:hidden}
.ai-section .ai-bg{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;opacity:.15}
.ai-content{position:relative;z-index:2}
.ai-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px;margin-top:40px}
.ai-card{background:rgba(22,22,42,.85);border:1px solid rgba(232,53,15,.15);border-radius:14px;padding:30px;backdrop-filter:blur(8px);transition:all .3s}
.ai-card:hover{border-color:#E8350F;box-shadow:0 0 30px rgba(232,53,15,.15)}
.ai-card h4{font-size:18px;margin-bottom:10px;color:#FF6B35}
.ai-card p{color:#9A9AB0;font-size:14px}

/* --- Expert Team --- */
.expert-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.expert-card{background:#16162A;border-radius:14px;overflow:hidden;text-align:center;border:1px solid rgba(154,154,176,.08);transition:all .3s}
.expert-card:hover{transform:translateY(-4px);box-shadow:0 8px 30px rgba(232,53,15,.15)}
.expert-card .avatar{width:120px;height:120px;border-radius:50%;margin:28px auto 16px;overflow:hidden;border:3px solid rgba(232,53,15,.3)}
.expert-card .avatar img{width:100%;height:100%;object-fit:cover}
.expert-card h4{font-size:17px;margin-bottom:4px}
.expert-card .role{color:#FF6B35;font-size:13px;margin-bottom:12px}
.expert-card p{color:#9A9AB0;font-size:13px;padding:0 20px;margin-bottom:16px;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.expert-card .expert-btns{display:flex;gap:8px;justify-content:center;padding:0 16px 24px}
.expert-card .expert-btns a{padding:6px 16px;font-size:12px;border-radius:20px;border:1px solid rgba(232,53,15,.4);color:#FF6B35;transition:all .3s}
.expert-card .expert-btns a:hover{background:#E8350F;color:#fff;border-color:#E8350F}

/* --- Partner Logo Wall --- */
.partner-wall{display:flex;flex-wrap:wrap;justify-content:center;gap:32px;align-items:center}
.partner-wall .partner-item{width:140px;height:70px;background:rgba(22,22,42,.6);border-radius:10px;display:flex;align-items:center;justify-content:center;border:1px solid rgba(154,154,176,.1);transition:all .3s;padding:12px}
.partner-wall .partner-item:hover{border-color:rgba(232,53,15,.3)}
.partner-wall .partner-item span{font-size:14px;color:#9A9AB0;font-weight:600;text-align:center}

/* --- Reviews --- */
.review-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px}
.rc5xtxp{background:#16162A;border-radius:14px;padding:28px;border:1px solid rgba(154,154,176,.08);transition:all .3s}
.rc5xtxp:hover{border-color:rgba(232,53,15,.2)}
.rc5xtxp .stars{color:#FF6B35;font-size:16px;margin-bottom:12px;letter-spacing:2px}
.rc5xtxp blockquote{color:#9A9AB0;font-size:14px;line-height:1.7;margin-bottom:16px;font-style:italic}
.rc5xtxp .reviewer{display:flex;align-items:center;gap:12px}
.rc5xtxp .reviewer .r-avatar{width:40px;height:40px;border-radius:50%;background:linear-gradient(135deg,#E8350F,#FF6B35);display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:16px}
.rc5xtxp .reviewer .r-info{font-size:14px;color:#F0F0F5}
.rc5xtxp .reviewer .r-info small{display:block;color:#9A9AB0;font-size:12px}

/* --- FAQ --- */
.faq-list{max-width:800px;margin:0 auto}
.fi6wugp{background:#16162A;border-radius:12px;margin-bottom:12px;border:1px solid rgba(154,154,176,.08);overflow:hidden}
.fi6wugp .fqqv13li{padding:18px 24px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-size:16px;font-weight:600;transition:background .3s}
.fi6wugp .fqqv13li:hover{background:rgba(232,53,15,.05)}
.fi6wugp .fqqv13li .arrow{font-size:20px;color:#FF6B35;transition:transform .3s}
.fi6wugp.open .fqqv13li .arrow{transform:rotate(180deg)}
.fi6wugp .fqaoydk1{max-height:0;overflow:hidden;transition:max-height .4s ease,padding .4s;padding:0 24px}
.fi6wugp.open .fqaoydk1{max-height:300px;padding:0 24px 18px}
.fi6wugp .fqaoydk1 p{color:#9A9AB0;font-size:14px;line-height:1.7}

/* --- Contact Section --- */
.cg6o26cin{display:grid;grid-template-columns:repeat(2,1fr);gap:40px;align-items:start}
.contact-info{background:#16162A;border-radius:14px;padding:36px;border:1px solid rgba(154,154,176,.08)}
.contact-info h3{font-size:22px;margin-bottom:20px;color:#FF6B35}
.contact-info .info-item{display:flex;align-items:flex-start;gap:12px;margin-bottom:16px;font-size:14px;color:#9A9AB0}
.contact-info .info-item strong{color:#F0F0F5;min-width:80px}
.contact-qr{display:flex;gap:24px;margin-top:24px}
.contact-qr .qr-item{text-align:center}
.contact-qr .qr-item img{width:140px;height:140px;border-radius:10px;border:2px solid rgba(232,53,15,.2)}
.contact-qr .qr-item p{margin-top:8px;font-size:13px;color:#9A9AB0}

/* --- How-To Guide --- */
.howto-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:36px}
.howto-step{text-align:center;padding:24px 16px;background:#16162A;border-radius:14px;border:1px solid rgba(154,154,176,.08)}
.howto-step .sn4c9cg{width:48px;height:48px;border-radius:50%;background:linear-gradient(135deg,#E8350F,#FF6B35);color:#fff;font-size:20px;font-weight:700;display:flex;align-items:center;justify-content:center;margin:0 auto 16px}
.howto-step h4{font-size:16px;margin-bottom:8px}
.howto-step p{color:#9A9AB0;font-size:13px}

/* --- Share Buttons --- */
.snhbvz{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin-top:20px}
.snhbvz a{display:flex;align-items:center;gap:6px;padding:8px 20px;border-radius:24px;font-size:13px;font-weight:500;color:#fff;transition:all .3s}
.snhbvz a:hover{transform:translateY(-2px);color:#fff}
.share-wechat{background:#07C160}
.share-weibo{background:#E6162D}
.share-douyin{background:#161823}
.share-bilibili{background:#00A1D6}

/* --- Footer --- */
.site-footer{background:#0A0A18;border-top:1px solid rgba(154,154,176,.08);padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:36px;margin-bottom:36px}
.footer-col h4{font-size:16px;margin-bottom:16px;color:#F0F0F5}
.footer-col p,.footer-col a{font-size:13px;color:#9A9AB0;display:block;margin-bottom:8px;transition:color .3s}
.footer-col a:hover{color:#FF6B35}
.footer-col .footer-logo{display:flex;align-items:center;gap:10px;margin-bottom:16px}
.footer-col .footer-logo img{height:36px}
.footer-col .footer-logo span{font-size:20px;font-weight:800;color:#E8350F}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid rgba(154,154,176,.06);font-size:13px;color:#9A9AB0}
.footer-bottom .update-time{margin-top:6px;font-size:12px;color:#666}

/* --- Breadcrumb --- */
.breadcrumb{padding:16px 0;font-size:13px;color:#9A9AB0}
.breadcrumb a{color:#FF6B35}
.breadcrumb span{margin:0 8px;color:#555}

/* --- Inner Page Hero --- */
.inner-hero{background:#16162A;padding:80px 0 40px;margin-top:68px;text-align:center;border-bottom:1px solid rgba(154,154,176,.08)}
.inner-hero h1{font-size:36px;margin-bottom:12px}
.inner-hero p{color:#9A9AB0;font-size:16px}

/* --- Community Cards --- */
.community-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.community-card{background:#16162A;border-radius:14px;padding:28px;border:1px solid rgba(154,154,176,.08);transition:all .3s}
.community-card:hover{border-color:rgba(232,53,15,.3)}
.community-card h4{font-size:18px;margin-bottom:10px}
.community-card p{color:#9A9AB0;font-size:14px;margin-bottom:14px}
.community-card .topic-tags{display:flex;gap:6px;flex-wrap:wrap}
.community-card .topic-tags span{font-size:11px;padding:3px 10px;background:rgba(232,53,15,.1);color:#FF6B35;border-radius:12px}

/* --- Lazy Load Placeholder --- */



/* --- Responsive --- */
@media(max-width:1024px){
  .feature-grid,.expert-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:repeat(2,1fr)}
  .howto-steps{grid-template-columns:repeat(2,1fr)}
  .ai-grid{grid-template-columns:1fr}
}
@media(max-width:768px){
  .hero-content h1{font-size:32px}
  .hero-banner{min-height:420px}
  .section-title h2{font-size:28px}
  .video-grid{grid-template-columns:repeat(auto-fill,minmax(260px,1fr))}
  .feature-grid,.community-grid{grid-template-columns:1fr}
  .expert-grid{grid-template-columns:repeat(2,1fr)}
  .review-grid{grid-template-columns:1fr}
  .cg6o26cin{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .howto-steps{grid-template-columns:1fr}
  .main-nav{display:none;position:absolute;top:68px;left:0;width:100%;background:rgba(13,13,26,.98);flex-direction:column;padding:20px;gap:4px;border-bottom:1px solid rgba(232,53,15,.15)}
  .main-nav.open{display:flex}
  .main-nav a{padding:12px 16px;width:100%}
  .menu-toggle{display:flex}
  .search-bar{margin-left:0;margin-top:12px;width:100%}
  .search-bar input{width:100%}
  .search-bar input:focus{width:100%}
  .header-inner{flex-wrap:wrap}
}
@media(max-width:480px){
  .hero-content h1{font-size:26px}
  .hero-content .hero-sub{font-size:16px}
  .expert-grid{grid-template-columns:1fr}
  .partner-wall .partner-item{width:110px;height:55px}
  .contact-qr{flex-direction:column;align-items:center}
}

/* --- Scrollbar --- */
::-webkit-scrollbar{width:8px}
::-webkit-scrollbar-track{background:#0D0D1A}
::-webkit-scrollbar-thumb{background:#2A2A45;border-radius:4px}
::-webkit-scrollbar-thumb:hover{background:#E8350F}

/* --- Selection --- */
::selection{background:rgba(232,53,15,.3);color:#fff}

/* --- Animations --- */
@keyframes fadeInUp{from{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}
.ash91qt8{animation:fadeInUp .6s ease forwards;opacity:0}

/* --- MCP Embed Placeholder --- */
.mcp-embed{background:#16162A;border:1px dashed rgba(232,53,15,.3);border-radius:14px;padding:40px;text-align:center;color:#9A9AB0;font-size:14px;margin-top:24px}

/* --- Breadcrumb Bar (首页面包屑导航栏) --- */
.bmefec{background:#16162A;padding:8px 0;margin-top:68px;border-bottom:1px solid rgba(154,154,176,.06);font-size:13px;color:#9A9AB0}
.bmefec a{color:#FF6B35;font-size:13px}

/* --- Update Notice Bar (时效性信号) --- */
.update-notice{background:linear-gradient(90deg,rgba(232,53,15,.08),rgba(255,107,53,.05));padding:10px 0;border-bottom:1px solid rgba(232,53,15,.1);font-size:13px;color:#9A9AB0;text-align:center}
.update-notice .container{display:flex;justify-content:center;gap:16px;flex-wrap:wrap}
.update-notice span{white-space:nowrap}

/* --- Expert Certification Tags --- */
.expert-certs{display:flex;gap:6px;justify-content:center;flex-wrap:wrap;padding:0 16px;margin-bottom:14px}
.expert-certs span{font-size:11px;padding:3px 10px;background:rgba(74,222,128,.1);color:#4ADE80;border-radius:12px;border:1px solid rgba(74,222,128,.2)}

/* --- Publish Date on Video Cards --- */
.p5gjhfk{font-size:12px;color:#666;margin-bottom:6px}