/* ============================================
   寸止挑战 - 原创CSS样式表
   配色方案：深蓝 #0B1120 + 赛车橙 #F97316 + 电光蓝 #0EA5E9
   ============================================ */
*{margin:0;padding:0;box-sizing:border-box}
:root{--primary:#F97316;--primary-dark:#EA580C;--accent:#0EA5E9;--accent-dark:#0284C7;--bg-dark:#0B1120;--bg-card:#111827;--bg-section:#0F172A;--text-main:#F1F5F9;--text-muted:#94A3B8;--text-dim:#64748B;--border:#1E293B;--gradient:linear-gradient(135deg,#F97316,#0EA5E9);--shadow:0 4px 24px rgba(0,0,0,.4);--radius:12px}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;background:var(--bg-dark);color:var(--text-main);line-height:1.7;overflow-x:hidden}
a{color:var(--accent);text-decoration:none;transition:color .3s}
a:hover{color:var(--primary)}
img{max-width:100%;height:auto;display:block}
.container{max-width:1280px;margin:0 auto;padding:0 20px}

/* === 导航栏 === */
.site-nav{position:fixed;top:0;left:0;width:100%;z-index:1000;background:rgba(11,17,32,.92);backdrop-filter:blur(12px);border-bottom:1px solid var(--border);transition:all .3s}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:68px;max-width:1280px;margin:0 auto;padding:0 20px}
.nav-logo{display:flex;align-items:center;gap:10px}
.nav-logo img{height:40px;width:auto}
.nav-logo span{font-size:1.3rem;font-weight:700;background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.nav-links{display:flex;gap:6px;list-style:none}
.nav-links a{padding:8px 16px;border-radius:8px;font-size:.92rem;color:var(--text-muted);transition:all .3s}
.nav-links a:hover,.nav-links a.active{color:#fff;background:rgba(249,115,22,.15)}
.nav-toggle{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:8px}
.nav-toggle span{width:24px;height:2px;background:var(--text-main);transition:all .3s}

/* === 搜索框 === */
.search-bar{background:var(--bg-section);padding:12px 0;border-bottom:1px solid var(--border)}
.search-inner{max-width:680px;margin:0 auto;display:flex;gap:8px;padding:0 20px}
.search-inner input{flex:1;padding:10px 18px;border-radius:24px;border:1px solid var(--border);background:var(--bg-card);color:var(--text-main);font-size:.95rem;outline:none;transition:border .3s}
.search-inner input:focus{border-color:var(--primary)}
.search-inner button{padding:10px 28px;border-radius:24px;border:none;background:var(--gradient);color:#fff;font-weight:600;cursor:pointer;transition:opacity .3s}
.search-inner button:hover{opacity:.85}

/* === 面包屑 === */
.breadcrumb{padding:14px 0;font-size:.85rem;color:var(--text-dim)}
.breadcrumb a{color:var(--text-muted)}
.breadcrumb span{margin:0 6px;color:var(--text-dim)}

/* === 英雄区 === */
.hero-zone{position:relative;min-height:520px;display:flex;align-items:center;overflow:hidden;margin-top:68px}
.hero-zone .hero-bg{position:absolute;inset:0;background-size:cover;background-position:center;filter:brightness(.45)}
.hero-zone .hero-overlay{position:absolute;inset:0;background:linear-gradient(180deg,rgba(11,17,32,.3) 0%,rgba(11,17,32,.85) 100%)}
.hero-content{position:relative;z-index:2;padding:60px 20px;max-width:1280px;margin:0 auto;width:100%}
.hero-content h1{font-size:2.8rem;font-weight:800;margin-bottom:16px;line-height:1.2}
.hero-content h1 em{font-style:normal;background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.hero-content p{font-size:1.15rem;color:var(--text-muted);max-width:640px;margin-bottom:28px}
.hero-btns{display:flex;gap:14px;flex-wrap:wrap}
.btn-primary{display:inline-flex;align-items:center;gap:8px;padding:14px 32px;border-radius:30px;background:var(--gradient);color:#fff;font-weight:600;font-size:1rem;transition:transform .3s,box-shadow .3s;border:none;cursor:pointer}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 30px rgba(249,115,22,.35);color:#fff}
.btn-outline{display:inline-flex;align-items:center;gap:8px;padding:14px 32px;border-radius:30px;border:2px solid var(--primary);color:var(--primary);font-weight:600;font-size:1rem;background:transparent;cursor:pointer;transition:all .3s}
.btn-outline:hover{background:var(--primary);color:#fff}

/* === 通用区块 === */
.section{padding:70px 0}
.section-alt{background:var(--bg-section)}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:2rem;font-weight:700;margin-bottom:10px}
.section-title h2 em{font-style:normal;color:var(--primary)}
.section-title p{color:var(--text-muted);font-size:1.05rem;max-width:600px;margin:0 auto}

/* === 视频卡片 === */
.video-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.video-card{background:var(--bg-card);border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);transition:transform .3s,box-shadow .3s}
.video-card:hover{transform:translateY(-6px);box-shadow:var(--shadow)}
.video-thumb{position:relative;aspect-ratio:16/9;overflow:hidden;cursor:pointer}
.video-thumb img{width:100%;height:100%;object-fit:cover;transition:transform .4s}
.video-card:hover .video-thumb img{transform:scale(1.06)}
.video-thumb video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:0}
.play-btn{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:60px;height:60px;border-radius:50%;background:rgba(249,115,22,.85);display:flex;align-items:center;justify-content:center;opacity:0;transition:opacity .3s;pointer-events:none}
.play-btn::after{content:'';border-style:solid;border-width:10px 0 10px 18px;border-color:transparent transparent transparent #fff;margin-left:3px}
.video-card:hover .play-btn{opacity:1}
.video-duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,.75);color:#fff;padding:2px 8px;border-radius:4px;font-size:.78rem}
.video-tags{position:absolute;top:8px;left:8px;display:flex;gap:4px;flex-wrap:wrap}
.video-tags span{background:rgba(14,165,233,.8);color:#fff;padding:2px 10px;border-radius:12px;font-size:.72rem}
.video-info{padding:16px}
.video-info h3{font-size:1.05rem;font-weight:600;margin-bottom:8px;line-height:1.4}
.video-info h3 a{color:var(--text-main)}
.video-info h3 a:hover{color:var(--primary)}
.video-meta{display:flex;gap:14px;font-size:.82rem;color:var(--text-dim)}
.video-meta span{display:flex;align-items:center;gap:4px}
.video-stats{display:flex;gap:12px;margin-top:10px;font-size:.8rem;color:var(--text-dim)}

/* === 分类标签 === */
.cat-tabs{display:flex;gap:8px;justify-content:center;margin-bottom:32px;flex-wrap:wrap}
.cat-tabs button{padding:8px 22px;border-radius:20px;border:1px solid var(--border);background:transparent;color:var(--text-muted);cursor:pointer;transition:all .3s;font-size:.9rem}
.cat-tabs button.active,.cat-tabs button:hover{background:var(--primary);color:#fff;border-color:var(--primary)}

/* === 专家卡片 === */
.expert-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.expert-card{background:var(--bg-card);border-radius:var(--radius);padding:28px;text-align:center;border:1px solid var(--border);transition:transform .3s}
.expert-card:hover{transform:translateY(-4px)}
.expert-card img{width:100px;height:100px;border-radius:50%;object-fit:cover;margin:0 auto 16px;border:3px solid var(--primary)}
.expert-card h4{font-size:1.1rem;margin-bottom:4px}
.expert-card .role{color:var(--primary);font-size:.88rem;margin-bottom:10px}
.expert-card p{color:var(--text-muted);font-size:.88rem;margin-bottom:14px}
.expert-card .expert-btns{display:flex;gap:8px;justify-content:center}
.expert-card .expert-btns a{padding:6px 16px;border-radius:16px;font-size:.82rem;border:1px solid var(--border);color:var(--text-muted);transition:all .3s}
.expert-card .expert-btns a:hover{border-color:var(--primary);color:var(--primary)}

/* === 功能模块网格 === */
.feature-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.feature-item{background:var(--bg-card);border-radius:var(--radius);padding:28px 20px;text-align:center;border:1px solid var(--border);transition:all .3s}
.feature-item:hover{border-color:var(--primary);transform:translateY(-3px)}
.feature-icon{width:56px;height:56px;border-radius:14px;background:rgba(249,115,22,.12);display:flex;align-items:center;justify-content:center;margin:0 auto 14px;font-size:1.6rem}
.feature-item h4{font-size:1rem;margin-bottom:6px}
.feature-item p{color:var(--text-muted);font-size:.85rem}

/* === FAQ === */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{border:1px solid var(--border);border-radius:var(--radius);margin-bottom:12px;overflow:hidden}
.faq-q{padding:18px 24px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-weight:600;transition:background .3s}
.faq-q:hover{background:rgba(249,115,22,.06)}
.faq-q::after{content:'+';font-size:1.4rem;color:var(--primary);transition:transform .3s}
.faq-item.open .faq-q::after{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .4s ease;padding:0 24px}
.faq-item.open .faq-a{max-height:300px;padding:0 24px 18px}
.faq-a p{color:var(--text-muted);font-size:.92rem;line-height:1.7}

/* === 用户评价 === */
.review-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px}
.review-card{background:var(--bg-card);border-radius:var(--radius);padding:24px;border:1px solid var(--border)}
.review-header{display:flex;align-items:center;gap:12px;margin-bottom:12px}
.review-avatar{width:44px;height:44px;border-radius:50%;background:var(--gradient);display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:1.1rem}
.review-name{font-weight:600}
.review-stars{color:var(--primary);font-size:.9rem;margin-top:2px}
.review-text{color:var(--text-muted);font-size:.92rem;line-height:1.7}

/* === 合作品牌 === */
.partner-wall{display:flex;gap:28px;justify-content:center;flex-wrap:wrap;align-items:center}
.partner-wall .partner-item{width:120px;height:60px;background:var(--bg-card);border-radius:8px;display:flex;align-items:center;justify-content:center;border:1px solid var(--border);color:var(--text-dim);font-size:.85rem;font-weight:600}

/* === 联系信息 === */
.contact-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:32px}
.contact-card{background:var(--bg-card);border-radius:var(--radius);padding:28px;border:1px solid var(--border)}
.contact-card h4{font-size:1.1rem;margin-bottom:14px;color:var(--primary)}
.contact-card p{color:var(--text-muted);font-size:.9rem;margin-bottom:8px}
.contact-card img{max-width:160px;margin-top:12px;border-radius:8px}

/* === 页脚 === */
.site-footer{background:var(--bg-section);border-top:1px solid var(--border);padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;margin-bottom:36px}
.footer-brand img{height:36px;margin-bottom:12px}
.footer-brand p{color:var(--text-muted);font-size:.88rem}
.footer-col h5{font-size:1rem;margin-bottom:14px;color:var(--text-main)}
.footer-col a{display:block;color:var(--text-muted);font-size:.88rem;margin-bottom:8px;transition:color .3s}
.footer-col a:hover{color:var(--primary)}
.footer-bottom{text-align:center;padding-top:24px;border-top:1px solid var(--border);color:var(--text-dim);font-size:.82rem}
.footer-qr{display:flex;gap:20px;margin-top:12px}
.footer-qr img{width:100px;border-radius:8px}
.footer-qr p{font-size:.78rem;text-align:center;color:var(--text-dim);margin-top:4px}

/* === 社交分享 === */
.share-bar{display:flex;gap:10px;justify-content:center;margin-top:20px}
.share-bar a{width:40px;height:40px;border-radius:50%;background:var(--bg-card);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;color:var(--text-muted);font-size:.9rem;transition:all .3s}
.share-bar a:hover{border-color:var(--primary);color:var(--primary);background:rgba(249,115,22,.1)}

/* === How-To 指南 === */
.howto-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;counter-reset:step}
.howto-step{background:var(--bg-card);border-radius:var(--radius);padding:24px;border:1px solid var(--border);position:relative;counter-increment:step}
.howto-step::before{content:counter(step);position:absolute;top:-14px;left:20px;width:32px;height:32px;border-radius:50%;background:var(--gradient);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.9rem}
.howto-step h4{margin-top:8px;margin-bottom:8px;font-size:.95rem}
.howto-step p{color:var(--text-muted);font-size:.85rem}

/* === 内页通用 === */
.page-hero{padding:100px 0 40px;background:var(--bg-section);margin-top:68px}
.page-hero h1{font-size:2.2rem;font-weight:700;margin-bottom:8px}
.page-hero p{color:var(--text-muted);font-size:1.05rem}

/* === 视频弹窗 === */
.video-modal{display:none;position:fixed;inset:0;z-index:9999;background:rgba(0,0,0,.88);align-items:center;justify-content:center}
.video-modal.active{display:flex}
.video-modal-inner{background:var(--bg-card);border-radius:var(--radius);padding:20px;max-width:800px;width:90%;position:relative}
.video-modal-close{position:absolute;top:-12px;right:-12px;width:36px;height:36px;border-radius:50%;background:var(--primary);color:#fff;border:none;font-size:1.2rem;cursor:pointer;display:flex;align-items:center;justify-content:center}
.video-modal-inner video{width:100%;border-radius:8px}

/* === 关于页面 === */
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center}
.about-grid img{border-radius:var(--radius)}
.timeline{position:relative;padding-left:30px}
.timeline::before{content:'';position:absolute;left:8px;top:0;bottom:0;width:2px;background:var(--border)}
.timeline-item{position:relative;margin-bottom:28px}
.timeline-item::before{content:'';position:absolute;left:-26px;top:4px;width:12px;height:12px;border-radius:50%;background:var(--primary)}
.timeline-item h4{font-size:1rem;margin-bottom:4px}
.timeline-item p{color:var(--text-muted);font-size:.88rem}

/* === 响应式 === */
@media(max-width:1024px){
.video-grid{grid-template-columns:repeat(2,1fr)}
.feature-grid{grid-template-columns:repeat(2,1fr)}
.expert-grid{grid-template-columns:repeat(2,1fr)}
.footer-grid{grid-template-columns:1fr 1fr}
.howto-steps{grid-template-columns:repeat(2,1fr)}
.about-grid{grid-template-columns:1fr}
}
@media(max-width:768px){
.nav-links{display:none;position:absolute;top:68px;left:0;width:100%;background:var(--bg-dark);flex-direction:column;padding:16px;border-bottom:1px solid var(--border)}
.nav-links.open{display:flex}
.nav-toggle{display:flex}
.hero-content h1{font-size:1.8rem}
.video-grid{grid-template-columns:1fr}
.feature-grid{grid-template-columns: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}
.howto-steps{grid-template-columns:1fr}
.section{padding:40px 0}
.section-title h2{font-size:1.5rem}
.hero-zone{min-height:400px}
}
@media(max-width:480px){
.hero-content h1{font-size:1.5rem}
.hero-btns{flex-direction:column}
.btn-primary,.btn-outline{width:100%;justify-content:center}
}

/* === 干扰标签隐藏 === */
.jammer{display:none!important}