/*
   高清视频 - 原创样式表
   品牌：高清视频 | dt537526.cn
   配色：赛道绿 + 碳纤维黑 + 霓虹黄
   作者：高清视频技术团队
   更新：2026
*/
:root {
  --kkt-green: #00C853;
  --kkt-dark: #0a0e14;
  --kkt-card: #111820;
  --kkt-border: #1e2a38;
  --kkt-yellow: #EEFF41;
  --kkt-text: #e0e6ed;
  --kkt-muted: #8899aa;
  --kkt-gradient: linear-gradient(135deg, #00C853 0%, #00E676 50%, #EEFF41 100%);
  --kkt-shadow: 0 8px 32px rgba(0,200,83,0.15);
  --kkt-radius: 14px;
}
* { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; }
body {
  font-family: 'PingFang SC','Hiragino Sans GB','Microsoft YaHei','Helvetica Neue',Arial,sans-serif;
  background: var(--kkt-dark);
  color: var(--kkt-text);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--kkt-green); text-decoration:none; transition: color .3s; }
a:hover { color: var(--kkt-yellow); }
img { max-width:100%; height:auto; display:block; }
.kkt-container { max-width:1200px; margin:0 auto; padding:0 20px; }

/* 导航栏 */
.kkt-header {
  position:fixed; top:0; left:0; width:100%; z-index:1000;
  background: rgba(10,14,20,0.92);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--kkt-border);
  padding: 0 24px;
  transition: all .3s;
}
.kkt-nav { display:flex; align-items:center; justify-content:space-between; height:68px; max-width:1200px; margin:0 auto; }
.kkt-logo-wrap { display:flex; align-items:center; gap:10px; }
.kkt-logo-wrap img { width:42px; height:42px; border-radius:8px; }
.kkt-logo-text { font-size:22px; font-weight:800; background:var(--kkt-gradient); -webkit-background-clip:text; -webkit-text-fill-color:transparent; background-clip:text; letter-spacing:1px; }
.kkt-nav-links { display:flex; gap:28px; list-style:none; }
.kkt-nav-links a { color:var(--kkt-muted); font-size:15px; font-weight:500; padding:6px 0; position:relative; }
.kkt-nav-links a:hover, .kkt-nav-links a.active { color:var(--kkt-green); }
.kkt-nav-links a::after { content:''; position:absolute; bottom:0; left:0; width:0; height:2px; background:var(--kkt-gradient); transition:width .3s; }
.kkt-nav-links a:hover::after { width:100%; }
.kkt-menu-btn { display:none; background:none; border:none; color:var(--kkt-text); font-size:26px; cursor:pointer; }

/* 搜索框 */
.kkt-search-bar {
  background: var(--kkt-card);
  border-bottom: 1px solid var(--kkt-border);
  padding: 12px 0;
  margin-top: 68px;
}
.kkt-search-inner { max-width:600px; margin:0 auto; display:flex; gap:10px; padding:0 20px; }
.kkt-search-inner input {
  flex:1; background:var(--kkt-dark); border:1px solid var(--kkt-border); border-radius:25px;
  padding:10px 20px; color:var(--kkt-text); font-size:14px; outline:none; transition:border .3s;
}
.kkt-search-inner input:focus { border-color:var(--kkt-green); }
.kkt-search-inner button {
  background:var(--kkt-gradient); border:none; border-radius:25px; padding:10px 24px;
  color:#000; font-weight:700; cursor:pointer; font-size:14px; transition:transform .2s;
}
.kkt-search-inner button:hover { transform:scale(1.05); }

/* Hero区域 */
.kkt-hero {
  position:relative; min-height:520px; display:flex; align-items:center; justify-content:center;
  background-size:cover; background-position:center; overflow:hidden;
}
.kkt-hero::before {
  content:''; position:absolute; inset:0;
  background: linear-gradient(180deg, rgba(10,14,20,0.7) 0%, rgba(10,14,20,0.4) 40%, rgba(10,14,20,0.85) 100%);
}
.kkt-hero-content { position:relative; text-align:center; padding:60px 20px; max-width:800px; }
.kkt-hero h1 { font-size:48px; font-weight:900; margin-bottom:16px; line-height:1.2; }
.kkt-hero h1 span { background:var(--kkt-gradient); -webkit-background-clip:text; -webkit-text-fill-color:transparent; background-clip:text; }
.kkt-hero p { font-size:18px; color:var(--kkt-muted); margin-bottom:30px; }
.kkt-hero-btns { display:flex; gap:16px; justify-content:center; flex-wrap:wrap; }
.kkt-btn-primary {
  background:var(--kkt-gradient); color:#000; padding:14px 36px; border-radius:30px;
  font-weight:700; font-size:16px; display:inline-flex; align-items:center; gap:8px; transition:all .3s;
}
.kkt-btn-primary:hover { transform:translateY(-3px); box-shadow:var(--kkt-shadow); color:#000; }
.kkt-btn-outline {
  border:2px solid var(--kkt-green); color:var(--kkt-green); padding:12px 32px; border-radius:30px;
  font-weight:600; font-size:16px; transition:all .3s;
}
.kkt-btn-outline:hover { background:var(--kkt-green); color:#000; }

/* 区块标题 */
.kkt-section { padding:70px 0; }
.kkt-section-head { text-align:center; margin-bottom:48px; }
.kkt-section-head h2 { font-size:34px; font-weight:800; margin-bottom:12px; }
.kkt-section-head h2 span { color:var(--kkt-green); }
.kkt-section-head p { color:var(--kkt-muted); font-size:16px; max-width:600px; margin:0 auto; }

/* 视频卡片网格 */
.kkt-grid { display:grid; grid-template-columns:repeat(auto-fill,minmax(280px,1fr)); gap:24px; }
.kkt-grid-3 { grid-template-columns:repeat(3,1fr); }
.kkt-grid-4 { grid-template-columns:repeat(4,1fr); }
.kkt-video-card {
  background:var(--kkt-card); border-radius:var(--kkt-radius); overflow:hidden;
  border:1px solid var(--kkt-border); transition:all .4s; position:relative;
}
.kkt-video-card:hover { transform:translateY(-6px); border-color:var(--kkt-green); box-shadow:var(--kkt-shadow); }
.kkt-video-thumb { position:relative; overflow:hidden; aspect-ratio:16/10; }
.kkt-video-thumb img, .kkt-video-thumb video { width:100%; height:100%; object-fit:cover; }
.kkt-play-btn {
  position:absolute; top:50%; left:50%; transform:translate(-50%,-50%) scale(0.8);
  width:60px; height:60px; background:rgba(0,200,83,0.85); border-radius:50%;
  display:flex; align-items:center; justify-content:center;
  opacity:0; transition:all .3s; cursor:pointer; border:none;
}
.kkt-play-btn::after { content:''; border-style:solid; border-width:10px 0 10px 18px; border-color:transparent transparent transparent #000; margin-left:3px; }
.kkt-video-card:hover .kkt-play-btn { opacity:1; transform:translate(-50%,-50%) scale(1); }
.kkt-video-card.playing .kkt-play-btn { opacity:0; }
.kkt-video-info { padding:16px; }
.kkt-video-info h3 { font-size:16px; font-weight:700; margin-bottom:8px; line-height:1.4; display:-webkit-box; -webkit-line-clamp:2; -webkit-box-orient:vertical; overflow:hidden; }
.kkt-video-meta { display:flex; gap:14px; color:var(--kkt-muted); font-size:13px; }
.kkt-video-meta span { display:flex; align-items:center; gap:4px; }
.kkt-video-tag {
  position:absolute; top:12px; left:12px; background:rgba(0,200,83,0.9); color:#000;
  padding:3px 10px; border-radius:4px; font-size:12px; font-weight:700;
}
.kkt-duration {
  position:absolute; bottom:12px; right:12px; background:rgba(0,0,0,0.75); color:#fff;
  padding:2px 8px; border-radius:4px; font-size:12px;
}

/* 分类标签 */
.kkt-tags { display:flex; gap:10px; flex-wrap:wrap; justify-content:center; margin-bottom:32px; }
.kkt-tag {
  background:var(--kkt-card); border:1px solid var(--kkt-border); padding:8px 20px;
  border-radius:25px; font-size:14px; color:var(--kkt-muted); cursor:pointer; transition:all .3s;
}
.kkt-tag:hover, .kkt-tag.active { background:var(--kkt-green); color:#000; border-color:var(--kkt-green); font-weight:600; }

/* 专家卡片 */
.kkt-expert-card {
  background:var(--kkt-card); border-radius:var(--kkt-radius); padding:32px 24px;
  text-align:center; border:1px solid var(--kkt-border); transition:all .4s;
}
.kkt-expert-card:hover { border-color:var(--kkt-green); box-shadow:var(--kkt-shadow); }
.kkt-expert-card img { width:100px; height:100px; border-radius:50%; margin:0 auto 16px; object-fit:cover; border:3px solid var(--kkt-green); }
.kkt-expert-card h4 { font-size:18px; margin-bottom:6px; }
.kkt-expert-card .role { color:var(--kkt-green); font-size:14px; margin-bottom:10px; }
.kkt-expert-card p { color:var(--kkt-muted); font-size:13px; line-height:1.6; }
.kkt-expert-btns { display:flex; gap:10px; justify-content:center; margin-top:16px; }
.kkt-expert-btns a {
  padding:6px 16px; border-radius:20px; font-size:13px; font-weight:600;
  border:1px solid var(--kkt-green); color:var(--kkt-green); transition:all .3s;
}
.kkt-expert-btns a:hover { background:var(--kkt-green); color:#000; }

/* FAQ手风琴 */
.kkt-faq-list { max-width:800px; margin:0 auto; }
.kkt-faq-item { border:1px solid var(--kkt-border); border-radius:var(--kkt-radius); margin-bottom:12px; overflow:hidden; }
.kkt-faq-q {
  padding:18px 24px; cursor:pointer; display:flex; justify-content:space-between; align-items:center;
  font-weight:600; font-size:16px; background:var(--kkt-card); transition:all .3s;
}
.kkt-faq-q:hover { color:var(--kkt-green); }
.kkt-faq-q::after { content:'+'; font-size:22px; color:var(--kkt-green); transition:transform .3s; }
.kkt-faq-item.open .kkt-faq-q::after { content:'-'; }
.kkt-faq-a { padding:0 24px; max-height:0; overflow:hidden; transition:all .4s; color:var(--kkt-muted); line-height:1.8; }
.kkt-faq-item.open .kkt-faq-a { padding:16px 24px; max-height:500px; }

/* 评论卡片 */
.kkt-review-card {
  background:var(--kkt-card); border-radius:var(--kkt-radius); padding:24px;
  border:1px solid var(--kkt-border); transition:all .3s;
}
.kkt-review-card:hover { border-color:var(--kkt-green); }
.kkt-review-stars { color:var(--kkt-yellow); font-size:16px; margin-bottom:10px; }
.kkt-review-text { color:var(--kkt-muted); font-size:14px; line-height:1.7; margin-bottom:12px; font-style:italic; }
.kkt-review-author { font-weight:600; font-size:14px; }
.kkt-review-date { color:var(--kkt-muted); font-size:12px; }

/* 合作品牌墙 */
.kkt-brand-wall { display:flex; flex-wrap:wrap; gap:24px; justify-content:center; align-items:center; }
.kkt-brand-item {
  background:var(--kkt-card); border:1px solid var(--kkt-border); border-radius:12px;
  padding:20px 32px; font-size:16px; font-weight:700; color:var(--kkt-muted);
  transition:all .3s; min-width:160px; text-align:center;
}
.kkt-brand-item:hover { border-color:var(--kkt-green); color:var(--kkt-green); }

/* How-To指南 */
.kkt-howto { max-width:800px; margin:0 auto; }
.kkt-howto-step {
  display:flex; gap:20px; align-items:flex-start; margin-bottom:28px;
  padding:20px; background:var(--kkt-card); border-radius:var(--kkt-radius);
  border:1px solid var(--kkt-border);
}
.kkt-step-num {
  min-width:48px; height:48px; background:var(--kkt-gradient); border-radius:50%;
  display:flex; align-items:center; justify-content:center; font-size:20px; font-weight:900; color:#000;
}
.kkt-step-content h4 { font-size:17px; margin-bottom:6px; }
.kkt-step-content p { color:var(--kkt-muted); font-size:14px; }

/* 文章卡片 */
.kkt-article-card {
  background:var(--kkt-card); border-radius:var(--kkt-radius); overflow:hidden;
  border:1px solid var(--kkt-border); transition:all .4s;
}
.kkt-article-card:hover { border-color:var(--kkt-green); transform:translateY(-4px); }
.kkt-article-card .thumb { aspect-ratio:16/9; overflow:hidden; }
.kkt-article-card .thumb img { width:100%; height:100%; object-fit:cover; transition:transform .4s; }
.kkt-article-card:hover .thumb img { transform:scale(1.05); }
.kkt-article-card .info { padding:16px; }
.kkt-article-card .info h3 { font-size:16px; margin-bottom:8px; }
.kkt-article-card .info p { color:var(--kkt-muted); font-size:13px; line-height:1.6; display:-webkit-box; -webkit-line-clamp:2; -webkit-box-orient:vertical; overflow:hidden; }

/* 产品卡片 */
.kkt-product-card {
  background:var(--kkt-card); border-radius:var(--kkt-radius); padding:28px 20px;
  text-align:center; border:1px solid var(--kkt-border); transition:all .4s;
}
.kkt-product-card:hover { border-color:var(--kkt-green); box-shadow:var(--kkt-shadow); }
.kkt-product-icon { font-size:42px; margin-bottom:14px; }
.kkt-product-card h4 { font-size:17px; margin-bottom:8px; }
.kkt-product-card p { color:var(--kkt-muted); font-size:13px; line-height:1.6; }

/* 分享按钮 */
.kkt-share { display:flex; gap:12px; justify-content:center; flex-wrap:wrap; }
.kkt-share a {
  width:48px; height:48px; border-radius:50%; display:flex; align-items:center; justify-content:center;
  background:var(--kkt-card); border:1px solid var(--kkt-border); font-size:18px; transition:all .3s;
}
.kkt-share a:hover { background:var(--kkt-green); color:#000; border-color:var(--kkt-green); }

/* 联系我们 */
.kkt-contact-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(260px,1fr)); gap:24px; }
.kkt-contact-item {
  background:var(--kkt-card); border-radius:var(--kkt-radius); padding:24px;
  border:1px solid var(--kkt-border); text-align:center;
}
.kkt-contact-item h4 { font-size:16px; margin-bottom:10px; color:var(--kkt-green); }
.kkt-contact-item p { color:var(--kkt-muted); font-size:14px; }
.kkt-contact-item img { width:140px; height:140px; margin:10px auto 0; border-radius:8px; }

/* 页脚 */
.kkt-footer {
  background: #060a0f;
  border-top:1px solid var(--kkt-border);
  padding:48px 0 24px;
}
.kkt-footer-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(200px,1fr)); gap:32px; margin-bottom:32px; }
.kkt-footer-col h4 { font-size:16px; margin-bottom:16px; color:var(--kkt-green); }
.kkt-footer-col a { display:block; color:var(--kkt-muted); font-size:14px; padding:4px 0; }
.kkt-footer-col a:hover { color:var(--kkt-green); }
.kkt-footer-bottom { text-align:center; padding-top:24px; border-top:1px solid var(--kkt-border); color:var(--kkt-muted); font-size:13px; }
.kkt-footer-logo { display:flex; align-items:center; gap:10px; margin-bottom:12px; }
.kkt-footer-logo img { width:36px; height:36px; border-radius:6px; }
.kkt-footer-logo span { font-size:18px; font-weight:800; color:var(--kkt-green); }

/* 面包屑 */
.kkt-breadcrumb { padding:14px 0; font-size:13px; color:var(--kkt-muted); }
.kkt-breadcrumb a { color:var(--kkt-muted); }
.kkt-breadcrumb a:hover { color:var(--kkt-green); }
.kkt-breadcrumb span { margin:0 6px; }

/* 友情链接 */
.kkt-friend-links { text-align:center; padding:16px 0; border-top:1px solid var(--kkt-border); margin-top:16px; }
.kkt-friend-links span { color:var(--kkt-muted); font-size:13px; margin-right:12px; }
.kkt-friend-links a { color:var(--kkt-muted); font-size:13px; margin:0 6px; }

/* 动画 */
@keyframes kktFadeUp { from { opacity:0; transform:translateY(30px); } to { opacity:1; transform:translateY(0); } }
.kkt-animate { opacity:0; transform:translateY(30px); transition:all .6s ease; }
.kkt-animate.show { opacity:1; transform:translateY(0); }

/* 干扰标签隐藏 */
.kkt-cloak { position:absolute; width:1px; height:1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0; opacity:0; pointer-events:none; }

/* 响应式 */
@media (max-width:768px) {
  .kkt-nav-links { display:none; position:fixed; top:68px; left:0; width:100%; background:var(--kkt-dark); flex-direction:column; padding:20px; gap:16px; border-bottom:1px solid var(--kkt-border); }
  .kkt-nav-links.open { display:flex; }
  .kkt-menu-btn { display:block; }
  .kkt-hero h1 { font-size:30px; }
  .kkt-hero { min-height:400px; }
  .kkt-section { padding:40px 0; }
  .kkt-section-head h2 { font-size:26px; }
  .kkt-grid-3, .kkt-grid-4 { grid-template-columns:1fr; }
  .kkt-grid { grid-template-columns:repeat(auto-fill,minmax(240px,1fr)); }
  .kkt-howto-step { flex-direction:column; align-items:center; text-align:center; }
  .kkt-footer-grid { grid-template-columns:1fr 1fr; }
}
@media (max-width:480px) {
  .kkt-hero h1 { font-size:24px; }
  .kkt-hero-btns { flex-direction:column; align-items:center; }
  .kkt-footer-grid { grid-template-columns:1fr; }
}