/* 国产视频 - 汽车改装视频社区 fn878.cn */
/* 原创配色：碳纤维黑#0d0d0d 赛车红#e63946 钛金灰#2b2d42 银色#8d99ae 白#edf2f4 */
*{margin:0;padding:0;box-sizing:border-box}
:root{--primary:#e63946;--dark:#0d0d0d;--gray:#2b2d42;--silver:#8d99ae;--light:#edf2f4;--accent:#f4a261;--card-bg:#1a1a2e;--text:#edf2f4;--text-muted:#8d99ae}
body{font-family:'PingFang SC','Microsoft YaHei','Helvetica Neue',Arial,sans-serif;background:var(--dark);color:var(--text);line-height:1.8;overflow-x:hidden}
a{color:var(--primary);text-decoration:none;transition:color .3s}
a:hover{color:var(--accent)}
img{max-width:100%;height:auto}
.container{max-width:1200px;margin:0 auto;padding:0 20px}

/* 顶部导航 */
.top-bar{background:rgba(13,13,13,.95);backdrop-filter:blur(10px);position:fixed;top:0;left:0;width:100%;z-index:1000;border-bottom:1px solid rgba(230,57,70,.3)}
.top-bar .container{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo-area{display:flex;align-items:center;gap:10px}
.logo-area img{height:42px;width:auto}
.brand-text{font-size:22px;font-weight:700;color:var(--light)}
.brand-text span{color:var(--primary)}
.nav-menu{display:flex;list-style:none;gap:24px}
.nav-menu a{color:var(--text-muted);font-size:15px;font-weight:500;padding:8px 0;position:relative;transition:color .3s}
.nav-menu a:hover,.nav-menu a.active{color:var(--primary)}
.nav-menu a::after{content:'';position:absolute;bottom:0;left:0;width:0;height:2px;background:var(--primary);transition:width .3s}
.nav-menu a:hover::after,.nav-menu a.active::after{width:100%}
.mobile-toggle{display:none;font-size:26px;color:var(--light);cursor:pointer;background:none;border:none}

/* 搜索框 */
.search-bar{background:var(--gray);padding:12px 0;border-bottom:1px solid rgba(141,153,174,.2)}
.search-bar .container{display:flex;justify-content:center}
.search-box{display:flex;width:560px;max-width:100%}
.search-box input{flex:1;padding:10px 18px;border:2px solid var(--silver);border-right:none;border-radius:25px 0 0 25px;background:rgba(255,255,255,.05);color:var(--text);font-size:15px;outline:none;transition:border-color .3s}
.search-box input:focus{border-color:var(--primary)}
.search-box button{padding:10px 24px;background:var(--primary);color:#fff;border:2px solid var(--primary);border-radius:0 25px 25px 0;cursor:pointer;font-size:15px;transition:background .3s}
.search-box button:hover{background:#c1121f}

/* Banner */
.banner{position:relative;height:520px;margin-top:68px;overflow:hidden;display:flex;align-items:center;justify-content:center}
.banner img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;filter:brightness(.55)}
.banner-content{position:relative;z-index:2;text-align:center;padding:20px}
.banner h1{font-size:48px;font-weight:800;color:#fff;text-shadow:0 4px 20px rgba(0,0,0,.6);margin-bottom:16px}
.banner h1 span{color:var(--primary)}
.banner p{font-size:20px;color:rgba(255,255,255,.85);max-width:700px;margin:0 auto;text-shadow:0 2px 10px rgba(0,0,0,.5)}
.banner-tags{margin-top:20px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap}
.banner-tags span{background:rgba(230,57,70,.8);color:#fff;padding:6px 16px;border-radius:20px;font-size:13px}

/* 面包屑 */
.breadcrumb{padding:14px 0;font-size:13px;color:var(--text-muted)}
.breadcrumb a{color:var(--silver)}
.breadcrumb a:hover{color:var(--primary)}

/* 通用标题 */
.section{padding:50px 0}
.section-title{text-align:center;margin-bottom:40px}
.section-title h2{font-size:32px;font-weight:700;color:var(--light);position:relative;display:inline-block}
.section-title h2::after{content:'';display:block;width:60px;height:3px;background:var(--primary);margin:10px auto 0}
.section-title p{color:var(--text-muted);font-size:15px;margin-top:8px}

/* 视频卡片网格 */
.video-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.video-card{background:var(--card-bg);border-radius:12px;overflow:hidden;transition:transform .3s,box-shadow .3s;cursor:pointer;position:relative}
.video-card:hover{transform:translateY(-6px);box-shadow:0 12px 35px rgba(230,57,70,.2)}
.video-card .thumb{position:relative;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(1.08)}
.video-card .play-btn{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%) scale(0);width:56px;height:56px;background:rgba(230,57,70,.9);border-radius:50%;display:flex;align-items:center;justify-content:center;transition:transform .3s;z-index:3}
.video-card .play-btn::after{content:'';border-left:20px solid #fff;border-top:12px solid transparent;border-bottom:12px solid transparent;margin-left:4px}
.video-card:hover .play-btn{transform:translate(-50%,-50%) scale(1)}
.video-card .duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,.8);color:#fff;padding:2px 8px;border-radius:4px;font-size:12px;z-index:3}
.video-card .card-info{padding:14px}
.video-card .card-info h3{font-size:15px;font-weight:600;color:var(--light);line-height:1.5;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-card .card-info .meta{display:flex;justify-content:space-between;margin-top:8px;font-size:12px;color:var(--text-muted)}
.video-card .card-info .tags{margin-top:6px}
.video-card .card-info .tags span{display:inline-block;background:rgba(230,57,70,.15);color:var(--primary);padding:2px 8px;border-radius:10px;font-size:11px;margin-right:4px}

/* 分类标签栏 */
.tab-bar{display:flex;gap:12px;margin-bottom:30px;flex-wrap:wrap;justify-content:center}
.tab-bar .tab{padding:8px 22px;border-radius:22px;background:var(--card-bg);color:var(--text-muted);font-size:14px;cursor:pointer;transition:all .3s;border:1px solid transparent}
.tab-bar .tab:hover,.tab-bar .tab.active{background:var(--primary);color:#fff;border-color:var(--primary)}

/* 专家卡片 */
.expert-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.expert-card{background:var(--card-bg);border-radius:12px;padding:28px 20px;text-align:center;transition:transform .3s,box-shadow .3s}
.expert-card:hover{transform:translateY(-5px);box-shadow:0 10px 30px rgba(230,57,70,.15)}
.expert-card img{width:100px;height:100px;border-radius:50%;object-fit:cover;border:3px solid var(--primary);margin-bottom:14px}
.expert-card h4{font-size:17px;color:var(--light);margin-bottom:4px}
.expert-card .role{color:var(--primary);font-size:13px;margin-bottom:10px}
.expert-card p{font-size:13px;color:var(--text-muted);line-height:1.6}
.expert-card .btn-group{margin-top:14px;display:flex;gap:8px;justify-content:center}
.expert-card .btn-group a{padding:6px 14px;border-radius:18px;font-size:12px;border:1px solid var(--primary);color:var(--primary);transition:all .3s}
.expert-card .btn-group a:hover{background:var(--primary);color:#fff}

/* FAQ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{background:var(--card-bg);border-radius:10px;margin-bottom:12px;overflow:hidden;border:1px solid rgba(141,153,174,.15)}
.faq-item .faq-q{padding:16px 20px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-weight:600;color:var(--light);font-size:15px;transition:background .3s}
.faq-item .faq-q:hover{background:rgba(230,57,70,.1)}
.faq-item .faq-q .arrow{transition:transform .3s;color:var(--primary);font-size:18px}
.faq-item.open .faq-q .arrow{transform:rotate(180deg)}
.faq-item .faq-a{padding:0 20px;max-height:0;overflow:hidden;transition:max-height .4s,padding .4s;color:var(--text-muted);font-size:14px;line-height:1.8}
.faq-item.open .faq-a{max-height:300px;padding:0 20px 16px}

/* 用户评论 */
.review-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.review-card{background:var(--card-bg);border-radius:12px;padding:24px;border-left:4px solid var(--primary)}
.review-card .stars{color:var(--accent);font-size:16px;margin-bottom:8px}
.review-card p{font-size:14px;color:var(--text-muted);line-height:1.7;font-style:italic}
.review-card .reviewer{margin-top:12px;display:flex;align-items:center;gap:10px}
.review-card .reviewer strong{color:var(--light);font-size:14px}
.review-card .reviewer span{color:var(--text-muted);font-size:12px}

/* 合作品牌墙 */
.brand-wall{display:flex;gap:30px;justify-content:center;flex-wrap:wrap;align-items:center}
.brand-wall .brand-item{background:var(--card-bg);padding:16px 28px;border-radius:10px;color:var(--silver);font-size:16px;font-weight:600;transition:all .3s;border:1px solid rgba(141,153,174,.15)}
.brand-wall .brand-item:hover{border-color:var(--primary);color:var(--primary)}

/* How-To指南 */
.howto-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:30px}
.howto-step{background:var(--card-bg);border-radius:12px;padding:28px 20px;text-align:center;position:relative}
.howto-step .step-num{width:40px;height:40px;background:var(--primary);color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:18px;margin:0 auto 14px}
.howto-step h4{color:var(--light);font-size:16px;margin-bottom:8px}
.howto-step p{color:var(--text-muted);font-size:13px}

/* 社交分享 */
.share-bar{display:flex;gap:14px;justify-content:center;margin-top:20px}
.share-bar a{width:44px;height:44px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;color:#fff;transition:transform .3s}
.share-bar a:hover{transform:scale(1.15)}
.share-wechat{background:#07c160}
.share-weibo{background:#e6162d}
.share-douyin{background:#000}
.share-bilibili{background:#00a1d6}

/* 联系信息 */
.contact-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.contact-card{background:var(--card-bg);border-radius:12px;padding:28px;text-align:center}
.contact-card h4{color:var(--light);font-size:17px;margin-bottom:12px}
.contact-card p{color:var(--text-muted);font-size:14px;line-height:1.7}
.contact-card img{max-width:140px;margin-top:12px;border-radius:8px}

/* 页脚 */
.footer{background:var(--gray);padding:40px 0 20px;border-top:2px solid var(--primary)}
.footer-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:30px;margin-bottom:30px}
.footer-col h4{color:var(--light);font-size:16px;margin-bottom:14px;position:relative;padding-bottom:8px}
.footer-col h4::after{content:'';position:absolute;bottom:0;left:0;width:30px;height:2px;background:var(--primary)}
.footer-col a{display:block;color:var(--text-muted);font-size:13px;padding:4px 0;transition:color .3s}
.footer-col a:hover{color:var(--primary)}
.footer-col p{color:var(--text-muted);font-size:13px;line-height:1.7}
.footer-bottom{text-align:center;padding-top:20px;border-top:1px solid rgba(141,153,174,.2);color:var(--text-muted);font-size:13px}
.footer-bottom a{color:var(--primary)}
.footer-logo{display:flex;align-items:center;gap:8px;margin-bottom:12px}
.footer-logo img{height:36px}

/* AI赋能模块 */
.ai-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.ai-card{background:var(--card-bg);border-radius:12px;padding:30px;text-align:center;border:1px solid rgba(141,153,174,.1);transition:all .3s}
.ai-card:hover{border-color:var(--primary);box-shadow:0 8px 25px rgba(230,57,70,.15)}
.ai-card .icon{font-size:42px;margin-bottom:14px}
.ai-card h4{color:var(--light);font-size:17px;margin-bottom:10px}
.ai-card p{color:var(--text-muted);font-size:13px;line-height:1.7}

/* 社区模块 */
.community-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.community-card{background:var(--card-bg);border-radius:12px;overflow:hidden;transition:transform .3s}
.community-card:hover{transform:translateY(-4px)}
.community-card .thumb{position:relative;padding-top:60%;overflow:hidden}
.community-card .thumb img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover}
.community-card .info{padding:16px}
.community-card .info h4{color:var(--light);font-size:15px;margin-bottom:6px}
.community-card .info p{color:var(--text-muted);font-size:13px}

/* 内页样式 */
.page-header{padding:100px 0 40px;background:linear-gradient(135deg,var(--dark),var(--gray))}
.page-header h1{font-size:36px;color:var(--light);font-weight:700}
.page-header p{color:var(--text-muted);font-size:16px;margin-top:8px}
.page-content{padding:40px 0 60px}

/* 视频播放页 */
.video-player{position:relative;padding-top:56.25%;background:#000;border-radius:12px;overflow:hidden;margin-bottom:30px}
.video-player video{position:absolute;top:0;left:0;width:100%;height:100%}
.video-info h1{font-size:24px;color:var(--light);margin-bottom:12px}
.video-info .meta-bar{display:flex;gap:20px;color:var(--text-muted);font-size:14px;margin-bottom:16px;flex-wrap:wrap}
.video-info .desc{color:var(--text-muted);font-size:14px;line-height:1.8;padding:16px;background:var(--card-bg);border-radius:10px}
.related-videos h3{font-size:20px;color:var(--light);margin:30px 0 20px}

/* 干扰标签容器 */
.noise-wrap{position:absolute;width:0;height:0;overflow:hidden;opacity:0;pointer-events:none}

/* 响应式 */
@media(max-width:1024px){
  .video-grid{grid-template-columns:repeat(3,1fr)}
  .expert-grid{grid-template-columns:repeat(2,1fr)}
  .howto-steps{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:768px){
  .nav-menu{display:none;position:fixed;top:68px;left:0;width:100%;background:rgba(13,13,13,.98);flex-direction:column;padding:20px;gap:0}
  .nav-menu.open{display:flex}
  .nav-menu a{padding:14px 0;border-bottom:1px solid rgba(141,153,174,.1)}
  .mobile-toggle{display:block}
  .video-grid{grid-template-columns:repeat(2,1fr)}
  .ai-grid{grid-template-columns:1fr}
  .community-grid{grid-template-columns:repeat(2,1fr)}
  .contact-grid{grid-template-columns:1fr}
  .review-grid{grid-template-columns:1fr}
  .banner{height:380px}
  .banner h1{font-size:30px}
  .banner p{font-size:16px}
  .section-title h2{font-size:24px}
  .search-box{width:100%}
}
@media(max-width:480px){
  .video-grid{grid-template-columns:1fr}
  .expert-grid{grid-template-columns:1fr}
  .howto-steps{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .banner{height:300px}
  .banner h1{font-size:24px}
}