/* ===== 快连下载站 kuailian-a.com.cn 公共样式 ===== */
:root{
  --primary:#1664ff;
  --primary-dark:#0b4fd6;
  --accent:#00d4ff;
  --grad:linear-gradient(135deg,#1664ff 0%,#6a5cff 55%,#00d4ff 120%);
  --text:#1c2433;
  --text-light:#5b6678;
  --bg:#f5f8ff;
  --card:#ffffff;
  --border:#e6ecf7;
  --radius:16px;
  --shadow:0 10px 30px rgba(22,100,255,.10);
  --maxw:1120px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  color:var(--text);background:var(--bg);line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--primary-dark)}
img{max-width:100%;display:block}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ===== 顶部导航 ===== */
.site-header{
  position:sticky;top:0;z-index:100;
  background:rgba(255,255,255,.92);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center;gap:10px;font-size:21px;font-weight:800;color:var(--text)}
.logo:hover{color:var(--text)}
.logo-mark{
  width:36px;height:36px;border-radius:10px;background:var(--grad);
  display:flex;align-items:center;justify-content:center;color:#fff;font-size:19px;
  box-shadow:0 4px 12px rgba(22,100,255,.35);
}
.logo span{color:var(--primary)}
.nav-links{display:flex;gap:6px;list-style:none;align-items:center}
.nav-links a{
  display:block;padding:8px 14px;border-radius:9px;color:var(--text);
  font-size:15px;font-weight:500;transition:.2s;
}
.nav-links a:hover{background:#eef4ff;color:var(--primary)}
.nav-links a.active{background:var(--grad);color:#fff}
.nav-toggle{display:none;background:none;border:none;font-size:26px;cursor:pointer;color:var(--text)}

/* ===== 按钮 ===== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 30px;border-radius:999px;font-size:16px;font-weight:700;
  border:none;cursor:pointer;transition:transform .15s,box-shadow .2s;
}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 8px 22px rgba(22,100,255,.35)}
.btn-primary:hover{color:#fff;transform:translateY(-2px);box-shadow:0 12px 28px rgba(22,100,255,.45)}
.btn-ghost{background:#fff;color:var(--primary);border:1.5px solid var(--primary)}
.btn-ghost:hover{background:#eef4ff;color:var(--primary-dark)}
.btn-lg{padding:16px 42px;font-size:17px}

/* ===== Hero ===== */
.hero{background:var(--grad);color:#fff;padding:72px 0 96px;position:relative;overflow:hidden}
.hero::after{
  content:"";position:absolute;right:-120px;top:-120px;width:420px;height:420px;
  background:radial-gradient(circle,rgba(255,255,255,.18),transparent 70%);border-radius:50%;
}
.hero-inner{position:relative;z-index:1;display:flex;align-items:center;gap:40px;flex-wrap:wrap}
.hero-text{flex:1;min-width:300px}
.hero h1{font-size:42px;line-height:1.3;margin-bottom:18px;font-weight:800}
.hero p.lead{font-size:18px;opacity:.94;margin-bottom:30px;max-width:560px}
.hero-badges{display:flex;gap:14px;flex-wrap:wrap;margin-top:26px}
.hero-badge{background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.28);padding:8px 16px;border-radius:999px;font-size:14px}
.hero-visual{flex:0 0 280px;text-align:center}
.hero-card{
  background:rgba(255,255,255,.13);border:1px solid rgba(255,255,255,.3);
  border-radius:24px;padding:36px 26px;backdrop-filter:blur(6px);
}
.hero-card .big-icon{font-size:72px;margin-bottom:12px}
.hero-card .ver{font-size:15px;opacity:.92}

/* ===== 通用区块 ===== */
.section{padding:64px 0}
.section.alt{background:#fff}
.section-head{text-align:center;max-width:680px;margin:0 auto 44px}
.section-head h2{font-size:31px;font-weight:800;margin-bottom:12px}
.section-head p{color:var(--text-light);font-size:16px}

/* ===== 平台卡片（首页下载入口） ===== */
.platform-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.platform-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:32px 24px;text-align:center;box-shadow:var(--shadow);transition:.2s;
}
.platform-card:hover{transform:translateY(-6px);border-color:#cdddff}
.platform-card .p-icon{font-size:46px;margin-bottom:14px}
.platform-card h3{font-size:19px;margin-bottom:6px}
.platform-card .p-meta{color:var(--text-light);font-size:13.5px;margin-bottom:18px}
.platform-card .btn{width:100%;padding:11px 16px;font-size:15px}

/* ===== 特性 ===== */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.feature-item{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:30px}
.feature-item .f-icon{font-size:34px;margin-bottom:14px}
.feature-item h3{font-size:18px;margin-bottom:8px}
.feature-item p{color:var(--text-light);font-size:14.5px}

/* ===== 步骤 ===== */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;counter-reset:step}
.step{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:30px;position:relative}
.step::before{
  counter-increment:step;content:counter(step);
  width:42px;height:42px;border-radius:50%;background:var(--grad);color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:19px;font-weight:800;margin-bottom:16px;
}
.step h3{font-size:18px;margin-bottom:8px}
.step p{color:var(--text-light);font-size:14.5px}

/* ===== 内容文章页 ===== */
.page-hero{background:var(--grad);color:#fff;padding:54px 0}
.breadcrumb{font-size:13.5px;opacity:.9;margin-bottom:14px}
.breadcrumb a{color:#fff;text-decoration:underline;opacity:.9}
.page-hero h1{font-size:34px;font-weight:800;margin-bottom:10px}
.page-hero p{opacity:.93;max-width:680px}
.layout{display:flex;gap:32px;align-items:flex-start;padding:48px 0}
.article{flex:1;min-width:0;background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:40px}
.article h2{font-size:24px;margin:34px 0 14px;padding-left:13px;border-left:5px solid var(--primary)}
.article h2:first-child{margin-top:0}
.article h3{font-size:19px;margin:24px 0 10px}
.article p{color:#39435a;margin-bottom:14px}
.article ul,.article ol{margin:0 0 16px 24px;color:#39435a}
.article li{margin-bottom:8px}
.article table{width:100%;border-collapse:collapse;margin:16px 0;font-size:14.5px}
.article th,.article td{border:1px solid var(--border);padding:11px 14px;text-align:left}
.article th{background:#f0f5ff}
.article .note{background:#f0f7ff;border-left:4px solid var(--primary);padding:14px 18px;border-radius:0 10px 10px 0;margin:18px 0;font-size:14.5px}
.article .warn{background:#fff7e8;border-left:4px solid #ff9800;padding:14px 18px;border-radius:0 10px 10px 0;margin:18px 0;font-size:14.5px}

/* 侧边栏 */
.sidebar{flex:0 0 300px;display:flex;flex-direction:column;gap:20px;position:sticky;top:84px}
.side-box{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:24px}
.side-box h3{font-size:17px;margin-bottom:16px}
.side-list{list-style:none}
.side-list li{border-bottom:1px dashed var(--border)}
.side-list li:last-child{border-bottom:none}
.side-list a{display:block;padding:10px 0;color:var(--text);font-size:14.5px}
.side-list a:hover{color:var(--primary)}
.dl-mini .btn{width:100%;margin-bottom:10px}
.side-ver{font-size:13.5px;color:var(--text-light);line-height:2}

/* ===== 下载详情块 ===== */
.dl-panel{background:linear-gradient(135deg,#f0f5ff,#f7f5ff);border:1px solid #d7e4ff;border-radius:var(--radius);padding:34px;margin:26px 0;text-align:center}
.dl-panel .dl-icon{font-size:58px;margin-bottom:8px}
.dl-panel h3{font-size:22px;margin-bottom:6px}
.dl-panel .dl-sub{color:var(--text-light);font-size:14.5px;margin-bottom:22px}
.dl-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.spec-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px;margin-top:22px;text-align:left}
.spec-grid div{background:#fff;border:1px solid var(--border);border-radius:10px;padding:12px 16px;font-size:14px}
.spec-grid b{color:var(--text)}

/* ===== FAQ 手风琴 ===== */
.faq-list{display:flex;flex-direction:column;gap:14px}
.faq-item{background:#fff;border:1px solid var(--border);border-radius:12px;overflow:hidden}
.faq-item summary{
  cursor:pointer;padding:18px 22px;font-size:16.5px;font-weight:600;list-style:none;
  display:flex;justify-content:space-between;align-items:center;
}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";font-size:24px;color:var(--primary);font-weight:400}
.faq-item[open] summary::after{content:"−"}
.faq-item .faq-a{padding:0 22px 20px;color:#39435a;font-size:15px}

/* ===== CTA ===== */
.cta{background:var(--grad);color:#fff;text-align:center;padding:60px 20px;border-radius:var(--radius);margin:8px 0}
.cta h2{font-size:29px;margin-bottom:12px}
.cta p{opacity:.93;margin-bottom:26px}
.cta .btn-ghost{background:transparent;color:#fff;border-color:#fff}
.cta .btn-ghost:hover{background:rgba(255,255,255,.15);color:#fff}

/* ===== 页脚 ===== */
.site-footer{background:#0e1525;color:#aeb8cc;padding:54px 0 0;margin-top:20px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:34px;padding-bottom:36px}
.footer-grid h4{color:#fff;font-size:16px;margin-bottom:16px}
.footer-grid ul{list-style:none}
.footer-grid li{margin-bottom:10px;font-size:14px}
.footer-grid a{color:#aeb8cc}
.footer-grid a:hover{color:#fff}
.footer-brand p{font-size:14px;margin:14px 0;max-width:320px}
.footer-bottom{border-top:1px solid #202a40;padding:18px 0;font-size:13px;text-align:center;color:#7e8aa3}
.footer-bottom a{color:#7e8aa3}

/* ===== 响应式 ===== */
@media (max-width:960px){
  .platform-grid{grid-template-columns:repeat(2,1fr)}
  .feature-grid,.steps{grid-template-columns:1fr}
  .layout{flex-direction:column}
  .sidebar{flex:none;width:100%;position:static}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media (max-width:680px){
  .nav-links{
    display:none;position:absolute;top:64px;left:0;right:0;background:#fff;
    flex-direction:column;gap:0;border-bottom:1px solid var(--border);padding:8px 0;
  }
  .nav-links.open{display:flex}
  .nav-links a{border-radius:0;padding:13px 22px}
  .nav-toggle{display:block}
  .hero h1{font-size:30px}
  .hero{padding:52px 0 70px}
  .section{padding:46px 0}
  .section-head h2{font-size:25px}
  .platform-grid{grid-template-columns:1fr}
  .article{padding:26px 20px}
  .spec-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
}