/* ============================================
   SA传媒 视频传媒 - 主样式表
   品牌: SA传媒 | 域名: tuxfs.cn
   ============================================ */

/* CSS Reset & Base */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;color:#e0e0e0;background:#0a0a0f;line-height:1.7;overflow-x:hidden}
a{color:#00b4ff;text-decoration:none;transition:color .3s}
a:hover{color:#ff6b35}
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:#fff}

/* Container */
.container{max-width:1200px;margin:0 auto;padding:0 20px}
.section-padding{padding:60px 0}

/* ============ Header & Navigation ============ */
.site-header{position:fixed;top:0;left:0;width:100%;z-index:1000;background:rgba(10,10,15,.95);backdrop-filter:blur(10px);border-bottom:1px solid rgba(0,180,255,.15);transition:all .3s}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;max-width:1200px;margin:0 auto}
.logo-wrap{display:flex;align-items:center;gap:10px}
.logo-wrap img{height:42px;width:auto}
.logo-text{font-size:1.3rem;font-weight:800;color:#00b4ff;letter-spacing:1px}
.logo-text span{color:#ff6b35}

/* Main Nav */
.main-nav{display:flex;align-items:center;gap:0}
.main-nav a{padding:10px 16px;font-size:.95rem;color:#ccc;font-weight:500;position:relative;transition:all .3s}
.main-nav a::after{content:'';position:absolute;bottom:0;left:50%;transform:translateX(-50%);width:0;height:2px;background:linear-gradient(90deg,#00b4ff,#ff6b35);transition:width .3s}
.main-nav a:hover,.main-nav a.active{color:#00b4ff}
.main-nav a:hover::after,.main-nav a.active::after{width:70%}

/* Mobile Menu Toggle */
.menu-toggle{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:5px}
.menu-toggle span{width:25px;height:2px;background:#fff;transition:all .3s}

/* Search Bar */
.search-bar{background:rgba(255,255,255,.05);border-bottom:1px solid rgba(0,180,255,.1);padding:10px 0}
.search-bar .container{display:flex;justify-content:center}
.search-input-wrap{position:relative;width:100%;max-width:600px}
.search-input-wrap input{width:100%;padding:10px 45px 10px 18px;border:1px solid rgba(0,180,255,.3);border-radius:25px;background:rgba(0,0,0,.4);color:#fff;font-size:.9rem;outline:none;transition:border-color .3s}
.search-input-wrap input:focus{border-color:#00b4ff}
.search-input-wrap input::placeholder{color:#666}
.search-input-wrap button{position:absolute;right:5px;top:50%;transform:translateY(-50%);background:linear-gradient(135deg,#00b4ff,#0088cc);border:none;color:#fff;width:34px;height:34px;border-radius:50%;cursor:pointer;font-size:1rem;display:flex;align-items:center;justify-content:center}

/* Breadcrumb */
.breadcrumb{padding:15px 0;font-size:.85rem;color:#888}
.breadcrumb a{color:#00b4ff}
.breadcrumb span{margin:0 8px;color:#555}

/* ============ Hero Banner ============ */
.hero-banner{position:relative;min-height:85vh;display:flex;align-items:center;justify-content:center;overflow:hidden;margin-top:66px}
.hero-banner .bg-image{position:absolute;inset:0;background-size:cover;background-position:center;filter:brightness(.45)}
.hero-banner .overlay{position:absolute;inset:0;background:linear-gradient(180deg,rgba(10,10,15,.3) 0%,rgba(10,10,15,.85) 100%)}
.hero-content{position:relative;z-index:2;text-align:center;max-width:850px;padding:40px 20px}
.hero-content h1{font-size:2.8rem;margin-bottom:15px;background:linear-gradient(135deg,#00b4ff,#ff6b35);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero-content h2{font-size:1.4rem;color:#ccc;font-weight:400;margin-bottom:25px}
.hero-content p{font-size:1.05rem;color:#aaa;margin-bottom:30px;line-height:1.8}
.hero-tags{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-bottom:30px}
.hero-tags span{padding:6px 16px;border:1px solid rgba(0,180,255,.3);border-radius:20px;font-size:.82rem;color:#00b4ff;background:rgba(0,180,255,.08)}
.hero-btns{display:flex;gap:15px;justify-content:center;flex-wrap:wrap}
.btn-primary{padding:12px 32px;background:linear-gradient(135deg,#00b4ff,#0088cc);color:#fff;border-radius:30px;font-weight:600;font-size:1rem;border:none;cursor:pointer;transition:all .3s;display:inline-block}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 25px rgba(0,180,255,.3);color:#fff}
.btn-outline{padding:12px 32px;border:1px solid #ff6b35;color:#ff6b35;border-radius:30px;font-weight:600;font-size:1rem;cursor:pointer;transition:all .3s;background:transparent;display:inline-block}
.btn-outline:hover{background:rgba(255,107,53,.15);color:#ff6b35}

/* ============ Section Titles ============ */
.section-title{text-align:center;margin-bottom:45px}
.section-title h2{font-size:2rem;margin-bottom:10px;color:#fff}
.section-title h3{font-size:1.1rem;color:#888;font-weight:400}
.section-title .line{width:60px;height:3px;background:linear-gradient(90deg,#00b4ff,#ff6b35);margin:15px auto 0;border-radius:2px}

/* ============ Video Cards Grid ============ */
.video-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:25px}
.video-card{background:rgba(255,255,255,.04);border-radius:12px;overflow:hidden;border:1px solid rgba(255,255,255,.06);transition:all .4s;cursor:pointer}
.video-card:hover{transform:translateY(-6px);border-color:rgba(0,180,255,.3);box-shadow:0 12px 35px rgba(0,0,0,.4)}
.video-thumb{position:relative;padding-top:56.25%;overflow:hidden}
.video-thumb img,.video-thumb video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform .5s}
.video-card:hover .video-thumb img,.video-card:hover .video-thumb video{transform:scale(1.08)}
.video-play-btn{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%) scale(0);width:60px;height:60px;background:rgba(0,180,255,.85);border-radius:50%;display:flex;align-items:center;justify-content:center;transition:all .4s;opacity:0}
.video-play-btn::after{content:'';width:0;height:0;border-style:solid;border-width:10px 0 10px 18px;border-color:transparent transparent transparent #fff;margin-left:3px}
.video-card:hover .video-play-btn{transform:translate(-50%,-50%) scale(1);opacity:1}
.video-duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,.8);color:#fff;padding:2px 8px;border-radius:4px;font-size:.75rem}
.video-date{position:absolute;top:8px;left:8px;background:rgba(0,180,255,.85);color:#fff;padding:2px 10px;border-radius:4px;font-size:.72rem;font-weight:500}
.video-info{padding:15px}
.video-info h4{font-size:.95rem;color:#eee;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-info h4 a{color:#eee;transition:color .3s}
.video-info h4 a:hover{color:#00b4ff}
.video-meta{display:flex;align-items:center;gap:12px;font-size:.8rem;color:#777}
.video-meta .views::before{content:'▶ '}
.video-meta .likes::before{content:'♥ '}
.video-meta .comments::before{content:'💬 '}
.video-tags{display:flex;gap:6px;margin-top:8px;flex-wrap:wrap}
.video-tags span{font-size:.72rem;padding:2px 8px;background:rgba(0,180,255,.1);color:#00b4ff;border-radius:10px}

/* ============ Trust Bar ============ */
.trust-bar{background:linear-gradient(90deg,rgba(0,180,255,.08),rgba(255,107,53,.05));border-bottom:1px solid rgba(0,180,255,.1);padding:12px 0;overflow:hidden}
.trust-items{display:flex;justify-content:center;gap:30px;flex-wrap:wrap;align-items:center}
.trust-item{display:flex;align-items:center;gap:6px;font-size:.82rem;color:#aaa;white-space:nowrap}
.trust-icon{font-size:1rem}
@media(max-width:768px){.trust-items{gap:15px;justify-content:flex-start;flex-wrap:nowrap;animation:trustScroll 20s linear infinite}}
@keyframes trustScroll{0%{transform:translateX(0)}100%{transform:translateX(-50%)}}

/* ============ Category Tabs ============ */
.category-tabs{display:flex;justify-content:center;gap:10px;margin-bottom:35px;flex-wrap:wrap}
.category-tabs .tab{padding:8px 22px;border:1px solid rgba(255,255,255,.1);border-radius:20px;color:#aaa;font-size:.88rem;cursor:pointer;transition:all .3s}
.category-tabs .tab:hover,.category-tabs .tab.active{background:linear-gradient(135deg,#00b4ff,#0088cc);color:#fff;border-color:transparent}

/* ============ Feature Cards ============ */
.feature-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:25px}
.feature-card{background:rgba(255,255,255,.03);border:1px solid rgba(255,255,255,.06);border-radius:12px;padding:30px 25px;text-align:center;transition:all .4s}
.feature-card:hover{border-color:rgba(0,180,255,.3);transform:translateY(-4px)}
.feature-icon{font-size:2.5rem;margin-bottom:15px}
.feature-card h4{font-size:1.1rem;margin-bottom:10px;color:#fff}
.feature-card p{font-size:.9rem;color:#888;line-height:1.6}

/* ============ Expert / Team Cards ============ */
.team-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:25px}
.team-card{background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.06);border-radius:12px;overflow:hidden;text-align:center;transition:all .4s}
.team-card:hover{border-color:rgba(0,180,255,.3);transform:translateY(-4px)}
.team-avatar{width:100%;height:200px;object-fit:cover}
.team-info{padding:20px}
.team-info h4{font-size:1.05rem;color:#fff;margin-bottom:5px}
.team-info .role{color:#00b4ff;font-size:.85rem;margin-bottom:10px}
.team-info p{font-size:.85rem;color:#888;line-height:1.6;margin-bottom:12px}
.team-links{display:flex;justify-content:center;gap:10px}
.team-links a{padding:6px 16px;border:1px solid rgba(0,180,255,.3);border-radius:15px;font-size:.8rem;color:#00b4ff;transition:all .3s}
.team-links a:hover{background:rgba(0,180,255,.15)}

/* ============ FAQ Section ============ */
.faq-list{max-width:800px;margin:0 auto}
.faq-item{border:1px solid rgba(255,255,255,.06);border-radius:10px;margin-bottom:12px;overflow:hidden;background:rgba(255,255,255,.02)}
.faq-question{padding:18px 20px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-weight:600;color:#eee;transition:background .3s}
.faq-question:hover{background:rgba(0,180,255,.05)}
.faq-question .arrow{transition:transform .3s;color:#00b4ff;font-size:1.2rem}
.faq-item.active .faq-question .arrow{transform:rotate(180deg)}
.faq-answer{padding:0 20px;max-height:0;overflow:hidden;transition:all .4s;color:#aaa;font-size:.92rem;line-height:1.8}
.faq-item.active .faq-answer{padding:0 20px 18px;max-height:500px}

/* ============ Reviews ============ */
.review-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}
.review-card{background:rgba(255,255,255,.03);border:1px solid rgba(255,255,255,.06);border-radius:12px;padding:25px;transition:all .3s}
.review-card:hover{border-color:rgba(0,180,255,.2)}
.review-stars{color:#ff6b35;margin-bottom:10px;font-size:1rem;letter-spacing:2px}
.review-text{font-size:.9rem;color:#bbb;line-height:1.7;margin-bottom:15px;font-style:italic}
.review-author{display:flex;align-items:center;gap:10px}
.review-author .avatar{width:36px;height:36px;border-radius:50%;background:linear-gradient(135deg,#00b4ff,#ff6b35);display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:.85rem}
.review-author .name{font-size:.85rem;color:#ddd}
.review-author .date{font-size:.75rem;color:#666}

/* ============ Partner Logos ============ */
.partner-wall{display:flex;flex-wrap:wrap;justify-content:center;gap:30px;align-items:center}
.partner-wall .partner-item{padding:15px 25px;background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.06);border-radius:10px;color:#888;font-size:.95rem;font-weight:600;transition:all .3s}
.partner-wall .partner-item:hover{border-color:rgba(0,180,255,.3);color:#00b4ff}

/* ============ Contact Section ============ */
.contact-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:25px}
.contact-card{background:rgba(255,255,255,.03);border:1px solid rgba(255,255,255,.06);border-radius:12px;padding:25px;text-align:center}
.contact-card h4{color:#fff;margin-bottom:12px;font-size:1rem}
.contact-card p{color:#aaa;font-size:.9rem;line-height:1.6}
.contact-card .highlight{color:#00b4ff;font-weight:600}

/* ============ How-To Guide ============ */
.howto-steps{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:20px;margin-top:30px}
.howto-step{text-align:center;padding:25px 20px;background:rgba(255,255,255,.03);border:1px solid rgba(255,255,255,.06);border-radius:12px;position:relative}
.howto-step .step-num{width:40px;height:40px;background:linear-gradient(135deg,#00b4ff,#0088cc);border-radius:50%;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:1.1rem;margin:0 auto 15px}
.howto-step h5{color:#fff;margin-bottom:8px}
.howto-step p{color:#888;font-size:.85rem;line-height:1.6}

/* ============ Share Buttons ============ */
.share-bar{display:flex;justify-content:center;gap:12px;padding:20px 0;flex-wrap:wrap}
.share-btn{padding:8px 20px;border-radius:20px;font-size:.85rem;font-weight:500;cursor:pointer;transition:all .3s;border:none;color:#fff}
.share-btn.wechat{background:#07c160}
.share-btn.weibo{background:#e6162d}
.share-btn.douyin{background:#161823}
.share-btn.bilibili{background:#fb7299}
.share-btn:hover{transform:translateY(-2px);opacity:.9}

/* ============ Footer ============ */
.site-footer{background:rgba(0,0,0,.6);border-top:1px solid rgba(0,180,255,.1);padding:50px 0 0}
.footer-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:30px;margin-bottom:40px}
.footer-col h5{color:#fff;font-size:1rem;margin-bottom:15px;position:relative;padding-bottom:10px}
.footer-col h5::after{content:'';position:absolute;bottom:0;left:0;width:30px;height:2px;background:#00b4ff}
.footer-col p,.footer-col a{color:#888;font-size:.88rem;line-height:2}
.footer-col a:hover{color:#00b4ff}
.footer-col .qr-code{width:120px;height:120px;background:rgba(255,255,255,.1);border-radius:8px;margin-top:10px;display:flex;align-items:center;justify-content:center;overflow:hidden}
.footer-col .qr-code img{width:100%;height:100%;object-fit:cover}
.footer-bottom{border-top:1px solid rgba(255,255,255,.06);padding:20px 0;text-align:center;color:#666;font-size:.82rem}
.footer-bottom a{color:#00b4ff}

/* ============ Inner Page Styles ============ */
.page-hero{padding:120px 0 50px;text-align:center;background:linear-gradient(180deg,rgba(0,180,255,.08) 0%,transparent 100%)}
.page-hero h1{font-size:2.2rem;margin-bottom:10px}
.page-hero p{color:#888;font-size:1rem}

.content-section{padding:40px 0}
.content-section h2{font-size:1.6rem;margin-bottom:20px;color:#fff}
.content-section h3{font-size:1.2rem;margin-bottom:15px;color:#ddd}
.content-section p{color:#aaa;font-size:.95rem;line-height:1.8;margin-bottom:15px}
.content-section article{margin-bottom:40px;padding:30px;background:rgba(255,255,255,.02);border:1px solid rgba(255,255,255,.05);border-radius:12px}

/* AI Section */
.ai-features{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:25px}
.ai-card{background:linear-gradient(135deg,rgba(0,180,255,.05),rgba(255,107,53,.03));border:1px solid rgba(0,180,255,.15);border-radius:12px;padding:30px;transition:all .4s}
.ai-card:hover{border-color:rgba(0,180,255,.4);transform:translateY(-4px)}
.ai-card h4{color:#00b4ff;margin-bottom:12px;font-size:1.05rem}
.ai-card p{color:#aaa;font-size:.9rem;line-height:1.7}

/* Data Stats */
.stats-bar{display:flex;justify-content:center;gap:40px;padding:40px 0;flex-wrap:wrap}
.stat-item{text-align:center}
.stat-item .num{font-size:2.5rem;font-weight:800;background:linear-gradient(135deg,#00b4ff,#ff6b35);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.stat-item .label{font-size:.85rem;color:#888;margin-top:5px}

/* ============ Lazy Load ============ */
.lazy{opacity:0;transition:opacity .5s}
.lazy.loaded{opacity:1}

/* ============ Scroll to Top ============ */
.scroll-top{position:fixed;bottom:30px;right:30px;width:45px;height:45px;background:linear-gradient(135deg,#00b4ff,#0088cc);border-radius:50%;display:flex;align-items:center;justify-content:center;color:#fff;font-size:1.2rem;cursor:pointer;opacity:0;visibility:hidden;transition:all .3s;z-index:999;border:none}
.scroll-top.visible{opacity:1;visibility:visible}
.scroll-top:hover{transform:translateY(-3px);box-shadow:0 5px 20px rgba(0,180,255,.4)}

/* ============ Responsive ============ */
@media(max-width:768px){
  .menu-toggle{display:flex}
  .main-nav{position:fixed;top:66px;left:0;width:100%;background:rgba(10,10,15,.98);flex-direction:column;padding:20px 0;transform:translateY(-120%);transition:transform .4s;border-bottom:1px solid rgba(0,180,255,.15)}
  .main-nav.open{transform:translateY(0)}
  .main-nav a{padding:12px 25px;font-size:1rem}
  .hero-content h1{font-size:1.8rem}
  .hero-content h2{font-size:1.1rem}
  .hero-banner{min-height:70vh}
  .section-title h2{font-size:1.5rem}
  .video-grid{grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:15px}
  .stats-bar{gap:20px}
  .stat-item .num{font-size:1.8rem}
  .footer-grid{grid-template-columns:1fr 1fr}
  .hero-btns{flex-direction:column;align-items:center}
}
@media(max-width:480px){
  .hero-content h1{font-size:1.5rem}
  .video-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .feature-grid{grid-template-columns:1fr}
  .team-grid{grid-template-columns:1fr}
  .review-grid{grid-template-columns:1fr}
}