/* ============================================
   足交 - 原创样式表
   配色：赛车红 #E63946 / 深海蓝 #1D3557 / 机油橙 #F4A261
   背景：暗夜黑 #0D1117 / 碳纤维灰 #161B22
   文字：月光白 #F1FAEE / 冰川蓝 #A8DADC
   ============================================ */

/* === 基础重置 === */
*,*::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:#0D1117;color:#F1FAEE;line-height:1.7;overflow-x:hidden}
a{color:#A8DADC;text-decoration:none;transition:color .3s}
a:hover{color:#E63946}
img{max-width:100%;height:auto;display:block}
ul,ol{list-style:none}
.container{max-width:1280px;margin:0 auto;padding:0 20px}

/* === 头部导航 === */
.site-header{background:rgba(13,17,23,.95);backdrop-filter:blur(12px);position:sticky;top:0;z-index:1000;border-bottom:1px solid rgba(230,57,70,.3)}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;max-width:1280px;margin:0 auto}
.logo-area{display:flex;align-items:center;gap:10px}
.logo-area img{height:42px;width:auto}
.logo-area .brand-name{font-size:28px;font-weight:800;color:#E63946;letter-spacing:2px}
.main-nav{display:flex;gap:6px}
.main-nav a{padding:8px 16px;border-radius:6px;font-size:15px;font-weight:500;color:#F1FAEE;transition:all .3s}
.main-nav a:hover,.main-nav a.active{background:#E63946;color:#fff}
.mobile-menu-btn{display:none;background:none;border:none;color:#F1FAEE;font-size:24px;cursor:pointer}

/* === 搜索框 === */
.search-bar{background:#161B22;padding:16px 0;border-bottom:1px solid rgba(168,218,220,.1)}
.search-bar .container{display:flex;justify-content:center}
.search-box{display:flex;max-width:640px;width:100%}
.search-box input{flex:1;padding:12px 20px;background:#0D1117;border:2px solid #1D3557;border-right:none;border-radius:8px 0 0 8px;color:#F1FAEE;font-size:15px;outline:none;transition:border-color .3s}
.search-box input:focus{border-color:#E63946}
.search-box input::placeholder{color:#6B7B8D}
.search-box button{padding:12px 28px;background:#E63946;color:#fff;border:2px solid #E63946;border-radius:0 8px 8px 0;font-size:15px;cursor:pointer;font-weight:600;transition:background .3s}
.search-box button:hover{background:#c62d3a}

/* === Banner === */
.hero-banner{position:relative;height:520px;overflow:hidden}
.hero-banner .banner-bg{position:absolute;inset:0;background-size:cover;background-position:center;filter:brightness(.55)}
.hero-banner .banner-overlay{position:absolute;inset:0;background:linear-gradient(135deg,rgba(13,17,23,.85) 0%,rgba(29,53,87,.6) 50%,rgba(230,57,70,.2) 100%)}
.hero-banner .banner-content{position:relative;z-index:2;height:100%;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;padding:0 20px}
.hero-banner h1{font-size:48px;font-weight:900;margin-bottom:16px;text-shadow:0 4px 20px rgba(0,0,0,.5)}
.hero-banner h1 .hl{color:#E63946}
.hero-banner .subtitle{font-size:20px;color:#A8DADC;margin-bottom:28px;max-width:700px}
.hero-banner .cta-group{display:flex;gap:16px;flex-wrap:wrap;justify-content:center}
.btn-primary{display:inline-block;padding:14px 36px;background:linear-gradient(135deg,#E63946,#c62d3a);color:#fff;border-radius:8px;font-size:16px;font-weight:700;transition:transform .3s,box-shadow .3s;border:none;cursor:pointer}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 24px rgba(230,57,70,.4);color:#fff}
.btn-secondary{display:inline-block;padding:14px 36px;background:transparent;color:#F1FAEE;border:2px solid #A8DADC;border-radius:8px;font-size:16px;font-weight:700;transition:all .3s;cursor:pointer}
.btn-secondary:hover{background:#A8DADC;color:#0D1117}

/* === 通用板块 === */
.section{padding:72px 0}
.section-dark{background:#0D1117}
.section-alt{background:#161B22}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:36px;font-weight:800;margin-bottom:12px}
.section-title h2 .hl{color:#E63946}
.section-title p{color:#A8DADC;font-size:17px;max-width:600px;margin:0 auto}
.section-title .tag{display:inline-block;background:rgba(230,57,70,.15);color:#E63946;padding:4px 14px;border-radius:20px;font-size:13px;font-weight:600;margin-bottom:10px}

/* === 视频卡片 === */
.video-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.video-card{background:#161B22;border-radius:12px;overflow:hidden;transition:transform .3s,box-shadow .3s;border:1px solid rgba(168,218,220,.08)}
.video-card:hover{transform:translateY(-6px);box-shadow:0 16px 40px rgba(230,57,70,.15)}
.video-card .thumb{position:relative;padding-top:56.25%;overflow:hidden}
.video-card .thumb img{position:absolute;inset: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:60px;height:60px;background:rgba(230,57,70,.9);border-radius:50%;display:flex;align-items:center;justify-content:center;transition:transform .3s;z-index:2}
.video-card .play-btn::after{content:"";width:0;height:0;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 .thumb .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:2}
.video-card .card-body{padding:16px}
.video-card .card-body h3{font-size:15px;font-weight:700;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;line-height:1.4}
.video-card .card-body .meta{display:flex;justify-content:space-between;color:#6B7B8D;font-size:13px}
.video-card .card-body .meta .views{color:#F4A261}

/* === 短视频风格 === */
.short-video-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}
.short-card{position:relative;border-radius:12px;overflow:hidden;padding-top:160%;background:#161B22}
.short-card img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform .4s}
.short-card:hover img{transform:scale(1.05)}
.short-card .short-overlay{position:absolute;inset:0;background:linear-gradient(to top,rgba(0,0,0,.8) 0%,transparent 50%);z-index:1}
.short-card .short-info{position:absolute;bottom:12px;left:12px;right:12px;z-index:2}
.short-card .short-info h4{font-size:14px;font-weight:600;margin-bottom:4px}
.short-card .short-info .stats{font-size:12px;color:#A8DADC}
.short-card .play-icon{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%) scale(0);width:48px;height:48px;background:rgba(230,57,70,.85);border-radius:50%;display:flex;align-items:center;justify-content:center;z-index:3;transition:transform .3s}
.short-card .play-icon::after{content:"";width:0;height:0;border-left:16px solid #fff;border-top:10px solid transparent;border-bottom:10px solid transparent;margin-left:3px}
.short-card:hover .play-icon{transform:translate(-50%,-50%) scale(1)}

/* === AI模块 === */
.ai-features{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.ai-card{background:linear-gradient(145deg,#161B22,#1a2332);border:1px solid rgba(168,218,220,.1);border-radius:14px;padding:32px;text-align:center;transition:all .3s}
.ai-card:hover{border-color:#E63946;box-shadow:0 0 30px rgba(230,57,70,.1)}
.ai-card .icon{width:64px;height:64px;margin:0 auto 20px;background:linear-gradient(135deg,#E63946,#F4A261);border-radius:16px;display:flex;align-items:center;justify-content:center;font-size:28px}
.ai-card h3{font-size:20px;font-weight:700;margin-bottom:12px}
.ai-card p{color:#A8DADC;font-size:14px;line-height:1.7}

/* === 专家卡片 === */
.expert-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.expert-card{background:#161B22;border-radius:14px;overflow:hidden;text-align:center;padding:28px 20px;border:1px solid rgba(168,218,220,.08);transition:all .3s}
.expert-card:hover{border-color:#F4A261;transform:translateY(-4px)}
.expert-card .avatar{width:100px;height:100px;border-radius:50%;margin:0 auto 16px;overflow:hidden;border:3px solid #E63946}
.expert-card .avatar img{width:100%;height:100%;object-fit:cover}
.expert-card h3{font-size:18px;font-weight:700;margin-bottom:4px}
.expert-card .role{color:#F4A261;font-size:14px;margin-bottom:12px}
.expert-card .bio{color:#A8DADC;font-size:13px;line-height:1.6;margin-bottom:16px}
.expert-card .expert-links{display:flex;gap:8px;justify-content:center}
.expert-card .expert-links a{padding:6px 14px;background:rgba(230,57,70,.15);color:#E63946;border-radius:6px;font-size:13px;transition:all .3s}
.expert-card .expert-links a:hover{background:#E63946;color:#fff}

/* === 品牌墙 === */
.brand-wall{display:flex;flex-wrap:wrap;justify-content:center;gap:32px;align-items:center}
.brand-wall .brand-item{background:#161B22;border:1px solid rgba(168,218,220,.1);border-radius:10px;padding:20px 32px;font-size:18px;font-weight:700;color:#A8DADC;transition:all .3s}
.brand-wall .brand-item:hover{border-color:#E63946;color:#E63946}

/* === FAQ === */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{background:#161B22;border:1px solid rgba(168,218,220,.08);border-radius:10px;margin-bottom:12px;overflow:hidden}
.faq-item .faq-q{padding:18px 24px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-weight:700;font-size:16px;transition:background .3s}
.faq-item .faq-q:hover{background:rgba(230,57,70,.05)}
.faq-item .faq-q .arrow{color:#E63946;font-size:20px;transition:transform .3s}
.faq-item.open .faq-q .arrow{transform:rotate(180deg)}
.faq-item .faq-a{padding:0 24px;max-height:0;overflow:hidden;transition:all .4s;color:#A8DADC;font-size:15px;line-height:1.8}
.faq-item.open .faq-a{padding:0 24px 18px;max-height:500px}

/* === 用户评论 === */
.review-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.review-card{background:#161B22;border-radius:12px;padding:24px;border:1px solid rgba(168,218,220,.08)}
.review-card .stars{color:#F4A261;font-size:16px;margin-bottom:12px}
.review-card .review-text{font-size:14px;color:#A8DADC;line-height:1.7;margin-bottom:16px;font-style:italic}
.review-card .reviewer{display:flex;align-items:center;gap:10px}
.review-card .reviewer .r-avatar{width:36px;height:36px;border-radius:50%;background:#1D3557;display:flex;align-items:center;justify-content:center;color:#F4A261;font-weight:700;font-size:14px}
.review-card .reviewer .r-info .r-name{font-size:14px;font-weight:600}
.review-card .reviewer .r-info .r-date{font-size:12px;color:#6B7B8D}

/* === 联系我们 === */
.contact-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.contact-card{background:#161B22;border-radius:12px;padding:28px;text-align:center;border:1px solid rgba(168,218,220,.08)}
.contact-card h3{font-size:18px;font-weight:700;margin-bottom:16px;color:#F4A261}
.contact-card p{color:#A8DADC;font-size:14px;line-height:1.8}
.contact-card .qr-placeholder{width:140px;height:140px;margin:12px auto;background:#1D3557;border-radius:10px;display:flex;align-items:center;justify-content:center;color:#A8DADC;font-size:13px}

/* === 社交分享 === */
.share-bar{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin-top:32px}
.share-bar a{display:inline-flex;align-items:center;gap:6px;padding:10px 20px;background:#161B22;border:1px solid rgba(168,218,220,.15);border-radius:8px;color:#F1FAEE;font-size:14px;transition:all .3s}
.share-bar a:hover{background:#E63946;border-color:#E63946;color:#fff}

/* === 页脚 === */
.site-footer{background:#0a0e14;border-top:1px solid rgba(230,57,70,.2);padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:32px;margin-bottom:36px}
.footer-col h4{font-size:16px;font-weight:700;margin-bottom:16px;color:#F4A261}
.footer-col p,.footer-col a{font-size:14px;color:#A8DADC;line-height:2}
.footer-col a:hover{color:#E63946}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid rgba(168,218,220,.08);color:#6B7B8D;font-size:13px}
.footer-bottom .update-time{margin-top:8px;color:#A8DADC;font-size:12px}

/* === 面包屑 === */
.breadcrumb{padding:14px 0;font-size:14px;color:#6B7B8D}
.breadcrumb a{color:#A8DADC}
.breadcrumb span{margin:0 8px;color:#6B7B8D}

/* === 内页通用 === */
.page-hero{padding:60px 0;text-align:center;background:linear-gradient(135deg,#0D1117 0%,#1D3557 100%)}
.page-hero h1{font-size:40px;font-weight:900;margin-bottom:12px}
.page-hero h1 .hl{color:#E63946}
.page-hero p{color:#A8DADC;font-size:17px}

/* === How-To指南 === */
.howto-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.step-card{background:#161B22;border-radius:12px;padding:28px;text-align:center;border:1px solid rgba(168,218,220,.08);position:relative}
.step-card .step-num{width:48px;height:48px;background:linear-gradient(135deg,#E63946,#F4A261);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:20px;font-weight:800;color:#fff;margin:0 auto 16px}
.step-card h3{font-size:17px;font-weight:700;margin-bottom:10px}
.step-card p{color:#A8DADC;font-size:14px}

/* === 社区模块 === */
.community-tabs{display:flex;gap:8px;justify-content:center;margin-bottom:32px;flex-wrap:wrap}
.community-tabs .tab{padding:10px 24px;background:#161B22;border:1px solid rgba(168,218,220,.15);border-radius:8px;color:#F1FAEE;font-size:14px;cursor:pointer;transition:all .3s}
.community-tabs .tab:hover,.community-tabs .tab.active{background:#E63946;border-color:#E63946;color:#fff}

/* === 响应式 === */
@media(max-width:1024px){
.video-grid{grid-template-columns:repeat(3,1fr)}
.short-video-grid{grid-template-columns:repeat(3,1fr)}
.expert-grid{grid-template-columns:repeat(2,1fr)}
.review-grid{grid-template-columns:repeat(2,1fr)}
.footer-grid{grid-template-columns:repeat(2,1fr)}
.ai-features{grid-template-columns:repeat(2,1fr)}
.howto-steps{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:768px){
.header-inner{flex-wrap:wrap}
.main-nav{display:none;width:100%;flex-direction:column;padding-top:12px}
.main-nav.show{display:flex}
.mobile-menu-btn{display:block}
.hero-banner{height:400px}
.hero-banner h1{font-size:32px}
.hero-banner .subtitle{font-size:16px}
.video-grid{grid-template-columns:repeat(2,1fr)}
.short-video-grid{grid-template-columns:repeat(2,1fr)}
.expert-grid{grid-template-columns:1fr}
.review-grid{grid-template-columns:1fr}
.contact-grid{grid-template-columns:1fr}
.footer-grid{grid-template-columns:1fr}
.ai-features{grid-template-columns:1fr}
.howto-steps{grid-template-columns:1fr}
.stats-grid{grid-template-columns:repeat(2,1fr)}
.section{padding:48px 0}
.section-title h2{font-size:28px}
.page-hero h1{font-size:28px}
.legal-content h2{font-size:18px}
}
@media(max-width:480px){
.video-grid{grid-template-columns:1fr}
.short-video-grid{grid-template-columns:repeat(2,1fr)}
.hero-banner{height:320px}
.hero-banner h1{font-size:26px}
.cta-group{flex-direction:column;align-items:center}
.stats-grid{grid-template-columns:1fr}
.stat-card .stat-num{font-size:28px}
}

/* === 视频标签云 === */
.section-tags{padding:20px 0;background:#161B22;border-bottom:1px solid rgba(168,218,220,.08)}
.tag-cloud{display:flex;flex-wrap:wrap;gap:10px;justify-content:center}
.video-tag{display:inline-block;padding:6px 16px;background:rgba(29,53,87,.6);border:1px solid rgba(168,218,220,.15);border-radius:20px;color:#A8DADC;font-size:13px;cursor:pointer;transition:all .3s}
.video-tag:hover,.video-tag.active{background:#E63946;border-color:#E63946;color:#fff}

/* === 卡片描述与标签 === */
.card-desc{color:#A8DADC;font-size:13px;line-height:1.6;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.card-tags{display:flex;gap:6px;flex-wrap:wrap;margin-top:8px}
.card-tags span{display:inline-block;padding:2px 10px;background:rgba(29,53,87,.5);border-radius:12px;font-size:11px;color:#A8DADC}
.meta .author{color:#F4A261}

/* === 专家资质徽章 === */
.credentials{display:flex;flex-wrap:wrap;gap:6px;justify-content:center;margin-bottom:12px}
.credential-badge{display:inline-block;padding:3px 10px;background:rgba(244,162,97,.12);border:1px solid rgba(244,162,97,.3);border-radius:12px;font-size:11px;color:#F4A261}
.expert-stats{display:flex;gap:16px;justify-content:center;color:#6B7B8D;font-size:12px;margin-bottom:12px}

/* === 统计网格 === */
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.stat-card{background:linear-gradient(145deg,#161B22,#1a2332);border:1px solid rgba(168,218,220,.1);border-radius:14px;padding:32px;text-align:center}
.stat-card .stat-num{font-size:36px;font-weight:900;color:#E63946;margin-bottom:8px}
.stat-card .stat-label{color:#A8DADC;font-size:14px}

/* === 法律内容 === */
.legal-content{max-width:800px;margin:0 auto}
.legal-content h2{font-size:22px;font-weight:700;margin:32px 0 16px;color:#F4A261;border-left:4px solid #E63946;padding-left:16px}
.legal-content p{color:#A8DADC;font-size:15px;line-height:1.9;margin-bottom:16px}

/* === 懒加载 === */
img[loading="lazy"]{opacity:0;transition:opacity .5s}
img[loading="lazy"].loaded,img[loading="lazy"][src]{opacity:1}

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