/* ============================================
   91 - 修车改装与视频社区 全站样式
   主色: #E8491D (橙红) #1B1B1B (炭黑) #2D2D2D (深灰)
   辅助: #F5A623 (金橙) #F7F7F7 (浅灰背景) #3A3A3A (中灰)
   强调: #00B4D8 (科技蓝)
   ============================================ */

/* Reset & Base */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","WenQuanYi Micro Hei",sans-serif;color:#333;background:#F7F7F7;line-height:1.7}
a{color:#E8491D;text-decoration:none;transition:color .3s}
a:hover{color:#F5A623}
img{max-width:100%;height:auto;display:block}
ul,ol{list-style:none}
h1,h2,h3,h4,h5,h6{color:#1B1B1B;line-height:1.3;font-weight:700}

/* Container */
.container{max-width:1200px;margin:0 auto;padding:0 20px}

/* ===== Header & Navigation ===== */
.site-header{background:#1B1B1B;position:sticky;top:0;z-index:1000;box-shadow:0 2px 16px rgba(0,0,0,.4)}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:0 20px;max-width:1200px;margin:0 auto;height:64px}
.logo-wrap{display:flex;align-items:center;gap:10px}
.logo-wrap img{width:40px;height:40px;border-radius:6px}
.logo-wrap .brand-name{color:#E8491D;font-size:24px;font-weight:900;letter-spacing:2px;font-style:italic}
.main-nav{display:flex;align-items:center;gap:0}
.main-nav a{color:rgba(255,255,255,.85);padding:20px 15px;font-size:14px;font-weight:500;transition:all .3s;border-bottom:3px solid transparent;display:inline-block}
.main-nav a:hover,.main-nav a.active{color:#E8491D;border-bottom-color:#E8491D;background:rgba(232,73,29,.06)}
.nav-toggle{display:none;background:none;border:none;color:#fff;font-size:26px;cursor:pointer}

/* Search Bar */
.search-bar{background:#2D2D2D;padding:10px 0}
.search-bar .container{display:flex;justify-content:center}
.search-box{display:flex;max-width:540px;width:100%;border-radius:6px;overflow:hidden;box-shadow:0 2px 8px rgba(0,0,0,.2)}
.search-box input{flex:1;padding:10px 18px;border:none;font-size:14px;outline:none;background:#3A3A3A;color:#fff}
.search-box input::placeholder{color:rgba(255,255,255,.5)}
.search-box button{padding:10px 22px;background:#E8491D;color:#fff;border:none;font-size:14px;cursor:pointer;font-weight:600;transition:background .3s}
.search-box button:hover{background:#F5A623}

/* ===== Banner ===== */
.hero-banner{position:relative;height:520px;overflow:hidden;background:#1B1B1B}
.hero-banner img{width:100%;height:100%;object-fit:cover;opacity:.65}
.hero-overlay{position:absolute;top:0;left:0;right:0;bottom:0;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:20px;background:linear-gradient(180deg,rgba(27,27,27,.2) 0%,rgba(27,27,27,.75) 100%)}
.hero-overlay h1{color:#fff;font-size:44px;margin-bottom:14px;text-shadow:0 3px 12px rgba(0,0,0,.5)}
.hero-overlay h1 span{color:#E8491D}
.hero-overlay p{color:rgba(255,255,255,.88);font-size:17px;max-width:700px;line-height:1.8}
.hero-cta{margin-top:24px;display:flex;gap:16px;flex-wrap:wrap;justify-content:center}

/* ===== Breadcrumb ===== */
.breadcrumb{padding:14px 0;font-size:14px;color:#666}
.breadcrumb a{color:#E8491D}
.breadcrumb span{margin:0 6px;color:#999}

/* ===== Section Titles ===== */
.section-title{text-align:center;margin-bottom:40px}
.section-title h2{font-size:30px;color:#1B1B1B;margin-bottom:10px;position:relative;display:inline-block}
.section-title h2::after{content:'';display:block;width:50px;height:4px;background:linear-gradient(90deg,#E8491D,#F5A623);margin:10px auto 0;border-radius:2px}
.section-title p{color:#666;font-size:15px;margin-top:8px}

/* ===== Sections ===== */
.section{padding:60px 0}
.section-dark{background:#1B1B1B;color:#fff}
.section-dark .section-title h2{color:#fff}
.section-dark .section-title p{color:rgba(255,255,255,.65)}
.section-alt{background:#fff}

/* ===== Video Cards ===== */
.video-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:22px}
.video-card{background:#fff;border-radius:10px;overflow:hidden;box-shadow:0 3px 14px rgba(0,0,0,.08);transition:transform .3s,box-shadow .3s;cursor:pointer}
.video-card:hover{transform:translateY(-5px);box-shadow:0 8px 24px rgba(0,0,0,.14)}
.video-thumb{position:relative;padding-top:56.25%;overflow:hidden;background:#1B1B1B}
.video-thumb img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;transition:transform .4s}
.video-card:hover .video-thumb img{transform:scale(1.06)}
.play-btn{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:58px;height:58px;background:rgba(232,73,29,.88);border-radius:50%;display:flex;align-items:center;justify-content:center;opacity:0;transition:opacity .3s,transform .3s}
.play-btn::after{content:'';width:0;height:0;border-style:solid;border-width:11px 0 11px 20px;border-color:transparent transparent transparent #fff;margin-left:3px}
.video-card:hover .play-btn{opacity:1;transform:translate(-50%,-50%) scale(1.1)}
.video-info{padding:14px 16px}
.video-info h3{font-size:15px;margin-bottom:8px;color:#1B1B1B;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-meta{display:flex;gap:12px;font-size:12px;color:#888}
.video-meta span{display:flex;align-items:center;gap:4px}
.video-tag{display:inline-block;padding:2px 10px;background:rgba(232,73,29,.08);color:#E8491D;border-radius:4px;font-size:12px;margin-top:8px;margin-right:6px}
.video-duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,.75);color:#fff;padding:2px 8px;border-radius:4px;font-size:12px}

/* ===== Expert Cards ===== */
.expert-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:22px}
.expert-card{background:#fff;border-radius:10px;padding:26px 18px;text-align:center;box-shadow:0 3px 14px rgba(0,0,0,.06);transition:transform .3s;border-top:3px solid #E8491D}
.expert-card:hover{transform:translateY(-4px)}
.expert-avatar{width:86px;height:86px;border-radius:50%;margin:0 auto 14px;background:#f0f0f0;overflow:hidden;border:3px solid #E8491D}
.expert-avatar img{width:100%;height:100%;object-fit:cover}
.expert-card h4{font-size:17px;color:#1B1B1B;margin-bottom:5px}
.expert-card .role{color:#E8491D;font-size:13px;margin-bottom:10px;font-weight:600}
.expert-card p{font-size:13px;color:#666;line-height:1.6;margin-bottom:12px}
.expert-btns{display:flex;gap:10px;justify-content:center}
.btn-sm{padding:6px 16px;border-radius:4px;font-size:12px;border:1px solid #E8491D;color:#E8491D;transition:all .3s;background:transparent;cursor:pointer}
.btn-sm:hover{background:#E8491D;color:#fff}

/* ===== FAQ ===== */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{background:#fff;border-radius:8px;margin-bottom:10px;box-shadow:0 2px 8px rgba(0,0,0,.05);overflow:hidden;border-left:3px solid #E8491D}
.faq-question{padding:16px 22px;font-size:15px;font-weight:600;color:#1B1B1B;cursor:pointer;display:flex;justify-content:space-between;align-items:center;transition:background .3s}
.faq-question:hover{background:#fafafa}
.faq-question::after{content:'+';font-size:20px;color:#E8491D;transition:transform .3s;font-weight:700}
.faq-item.active .faq-question::after{transform:rotate(45deg)}
.faq-answer{padding:0 22px;max-height:0;overflow:hidden;transition:all .4s ease;color:#555;line-height:1.8;font-size:14px}
.faq-item.active .faq-answer{padding:0 22px 16px;max-height:500px}

/* ===== Reviews ===== */
.review-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:22px}
.review-card{background:#fff;border-radius:10px;padding:22px;box-shadow:0 3px 12px rgba(0,0,0,.06)}
.review-header{display:flex;align-items:center;gap:12px;margin-bottom:12px}
.review-avatar{width:46px;height:46px;border-radius:50%;background:#2D2D2D;display:flex;align-items:center;justify-content:center;font-size:18px;color:#E8491D;font-weight:700}
.review-name{font-weight:600;color:#1B1B1B;font-size:14px}
.review-date{font-size:12px;color:#999}
.review-stars{color:#F5A623;font-size:14px;margin-bottom:8px;letter-spacing:2px}
.review-text{font-size:13px;color:#555;line-height:1.7}

/* ===== Contact Section ===== */
.contact-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:22px}
.contact-card{background:#fff;border-radius:10px;padding:22px;text-align:center;box-shadow:0 3px 12px rgba(0,0,0,.06);border-top:3px solid #F5A623}
.contact-card h4{color:#1B1B1B;margin-bottom:10px;font-size:16px}
.contact-card p{color:#555;font-size:13px;line-height:1.7}

/* ===== Share Buttons ===== */
.share-bar{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;padding:20px 0}
.share-btn{padding:8px 20px;border-radius:4px;font-size:13px;color:#fff;cursor:pointer;border:none;transition:opacity .3s;font-weight:600}
.share-btn:hover{opacity:.85}
.share-wechat{background:#07c160}
.share-weibo{background:#e6162d}
.share-douyin{background:#1B1B1B}
.share-bilibili{background:#00a1d6}

/* ===== Footer ===== */
.site-footer{background:#1B1B1B;color:rgba(255,255,255,.7);padding:48px 0 0}
.footer-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:30px;margin-bottom:36px}
.footer-col h4{color:#E8491D;font-size:16px;margin-bottom:14px;font-weight:700}
.footer-col p,.footer-col a{color:rgba(255,255,255,.6);font-size:13px;line-height:2}
.footer-col a:hover{color:#F5A623}
.footer-logo{display:flex;align-items:center;gap:10px;margin-bottom:14px}
.footer-logo img{width:44px;height:44px;border-radius:6px}
.footer-logo .brand-name{color:#E8491D;font-size:20px;font-weight:900;font-style:italic}
.footer-qr{display:flex;gap:18px;margin-top:14px}
.footer-qr img{width:100px;height:100px;border-radius:6px;border:2px solid rgba(255,255,255,.1)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding:18px 0;text-align:center;font-size:12px;color:rgba(255,255,255,.45)}
.footer-bottom a{color:#E8491D}

/* ===== How-To Guide ===== */
.howto-steps{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:22px;margin-top:28px}
.howto-step{background:#fff;border-radius:10px;padding:26px 18px;text-align:center;box-shadow:0 3px 12px rgba(0,0,0,.06);position:relative}
.step-number{width:42px;height:42px;background:linear-gradient(135deg,#E8491D,#F5A623);color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;font-weight:700;margin:0 auto 14px}
.howto-step h4{color:#1B1B1B;margin-bottom:8px;font-size:16px}
.howto-step p{color:#666;font-size:13px;line-height:1.6}

/* ===== Category Grid ===== */
.cat-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:18px}
.cat-card{background:#fff;border-radius:10px;overflow:hidden;text-align:center;box-shadow:0 3px 12px rgba(0,0,0,.06);transition:transform .3s}
.cat-card:hover{transform:translateY(-4px)}
.cat-card img{width:100%;height:120px;object-fit:cover}
.cat-card h4{padding:12px 10px;color:#1B1B1B;font-size:14px}

/* ===== Buttons ===== */
.btn-primary{display:inline-block;padding:12px 30px;background:#E8491D;color:#fff;border-radius:4px;font-size:15px;font-weight:700;border:none;cursor:pointer;transition:all .3s;text-transform:uppercase;letter-spacing:1px}
.btn-primary:hover{background:#F5A623;transform:translateY(-2px);box-shadow:0 4px 12px rgba(232,73,29,.3)}
.btn-outline{display:inline-block;padding:10px 26px;border:2px solid #E8491D;color:#E8491D;border-radius:4px;font-size:14px;font-weight:700;transition:all .3s;background:transparent;letter-spacing:1px}
.btn-outline:hover{background:#E8491D;color:#fff}
.btn-outline-white{display:inline-block;padding:10px 26px;border:2px solid #fff;color:#fff;border-radius:4px;font-size:14px;font-weight:700;transition:all .3s;background:transparent}
.btn-outline-white:hover{background:#fff;color:#1B1B1B}

/* ===== Page Content ===== */
.page-hero{background:#1B1B1B;padding:56px 0;text-align:center;color:#fff;position:relative;overflow:hidden}
.page-hero::before{content:'';position:absolute;top:0;left:0;right:0;bottom:0;background:linear-gradient(135deg,rgba(232,73,29,.15),rgba(245,166,35,.1));pointer-events:none}
.page-hero h1{font-size:34px;color:#fff;margin-bottom:10px;position:relative}
.page-hero h1 span{color:#E8491D}
.page-hero p{color:rgba(255,255,255,.8);font-size:16px;max-width:600px;margin:0 auto;position:relative}
.page-content{padding:50px 0}
.page-content p{margin-bottom:16px;font-size:14px;line-height:1.8;color:#444}
.page-content h2{font-size:24px;color:#1B1B1B;margin:28px 0 14px}
.page-content h3{font-size:19px;color:#E8491D;margin:22px 0 10px}

/* ===== Partner Logos ===== */
.partner-wall{display:flex;flex-wrap:wrap;gap:18px;justify-content:center;align-items:center;padding:28px 0}
.partner-logo{width:140px;height:65px;background:#fff;border-radius:8px;display:flex;align-items:center;justify-content:center;box-shadow:0 2px 8px rgba(0,0,0,.06);padding:10px;font-size:13px;color:#1B1B1B;font-weight:700;border:1px solid #eee}

/* ===== MCP Frontend ===== */
.mcp-widget{background:#2D2D2D;border-radius:10px;padding:22px;margin:20px 0;color:#fff}
.mcp-widget h4{color:#E8491D;margin-bottom:10px}
.mcp-widget .mcp-status{display:flex;align-items:center;gap:8px;font-size:13px}
.mcp-dot{width:8px;height:8px;border-radius:50%;background:#F5A623;animation:pulse 2s infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.4}}

/* ===== Responsive ===== */
@media(max-width:768px){
  .header-inner{flex-wrap:wrap;height:auto;padding:10px 20px}
  .main-nav{display:none;flex-direction:column;width:100%;padding:10px 0}
  .main-nav.show{display:flex}
  .main-nav a{padding:12px 20px;border-bottom:1px solid rgba(255,255,255,.08)}
  .nav-toggle{display:block}
  .hero-banner{height:340px}
  .hero-overlay h1{font-size:28px}
  .hero-overlay p{font-size:14px}
  .section{padding:40px 0}
  .section-title h2{font-size:24px}
  .video-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr))}
  .footer-grid{grid-template-columns:1fr}
  .footer-qr{justify-content:center}
}
@media(max-width:480px){
  .hero-banner{height:260px}
  .hero-overlay h1{font-size:22px}
  .video-grid{grid-template-columns:1fr}
  .expert-grid{grid-template-columns:1fr}
  .search-box{margin:0 10px}
  .hero-cta{flex-direction:column;align-items:center}
}

/* Interference tags - hidden */
div[aria-hidden="true"]{position:absolute;width:0;height:0;overflow:hidden;clip:rect(0,0,0,0);opacity:0;pointer-events:none;margin:0;padding:0;border:0}