:root{
  --midnight:#07142b;
  --midnight-2:#0d2144;
  --midnight-3:#122b57;
  --accent:#2563eb;
  --accent-light:#60a5fa;
  --paper:#f4f7fb;
  --white:#ffffff;
  --head-gray:#475569;
  --ink:#0f172a;
  --mute:#64748b;
  --line:#e2e8f0;
  --dark-line:rgba(255,255,255,.14);
  --max:1180px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  color:var(--ink);
  background:var(--paper);
  font:16px/1.68 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;height:auto;display:block}
.wrap{width:min(var(--max),calc(100% - 40px));margin:0 auto}

/* Top Navigation */
.site-nav{
  position:sticky;top:0;z-index:40;
  background:rgba(7,20,43,.94);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--dark-line);
  color:#fff;
}
.nav-inner{
  height:72px;
  display:grid;
  grid-template-columns:auto 1fr auto;
  align-items:center;
  gap:24px;
}
.brand{
  display:inline-flex;align-items:center;gap:10px;
  font-weight:800;font-size:18px;letter-spacing:.3px;color:#fff;
}
.brand-mark{
  width:34px;height:34px;border-radius:8px;
  display:grid;place-items:center;
  background:#fff;color:var(--midnight);
  font-weight:900;font-size:16px;
}
.nav-links{
  display:flex;justify-content:center;gap:28px;
  font-size:14px;color:rgba(255,255,255,.84);
}
.nav-links a:hover{color:#fff}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:44px;padding:0 20px;border-radius:8px;
  font-weight:700;font-size:14px;
  background:var(--accent);color:#fff;
  border:1px solid transparent;
  transition:transform .15s ease,background .15s ease;
}
.btn:hover{background:#1d4ed8;transform:translateY(-1px)}
.btn-light{background:#fff;color:var(--midnight)}
.btn-light:hover{background:#e2e8f0}
.btn-ghost{
  background:transparent;color:#fff;
  border-color:rgba(255,255,255,.28);
}
.btn-ghost:hover{background:rgba(255,255,255,.08)}

/* Midnight Full-Width Stage + Peeking White Table Header */
.midnight-stage{
  position:relative;
  background:
    radial-gradient(900px 420px at 85% 18%,rgba(96,165,250,.18),transparent 60%),
    linear-gradient(180deg,var(--midnight) 0%,var(--midnight-2) 68%,var(--midnight-3) 100%);
  color:#fff;
  padding:64px 0 0;
  overflow:hidden;
}
.hero-grid{
  display:grid;
  grid-template-columns:1.08fr .92fr;
  gap:40px;
  align-items:center;
  padding-bottom:54px;
}
.badge{
  display:inline-flex;align-items:center;gap:8px;
  padding:5px 12px;border-radius:999px;
  background:rgba(255,255,255,.1);
  border:1px solid var(--dark-line);
  font-size:12px;font-weight:700;color:#dbeafe;letter-spacing:.6px;
}
.midnight-stage h1{
  font-size:clamp(34px,4.6vw,56px);
  line-height:1.14;
  margin:16px 0 14px;
  letter-spacing:-.8px;
}
.hero-sub{
  font-size:17px;color:rgba(255,255,255,.86);
  margin:0 0 20px;max-width:620px;
}
.hero-tags{
  display:flex;flex-wrap:wrap;gap:8px;margin-bottom:26px;
}
.hero-tags span{
  padding:5px 11px;border-radius:6px;
  background:rgba(255,255,255,.08);
  border:1px solid var(--dark-line);
  font-size:13px;color:#e2e8f0;
}
.hero-actions{display:flex;flex-wrap:wrap;gap:12px}
.hero-card{
  background:rgba(255,255,255,.06);
  border:1px solid var(--dark-line);
  border-radius:14px;
  padding:14px;
  box-shadow:0 24px 60px rgba(0,0,0,.35);
}
.hero-card img{
  border-radius:10px;
  width:100%;aspect-ratio:16/10;object-fit:cover;
}
.hero-card-bar{
  display:flex;justify-content:space-between;align-items:center;
  padding:10px 4px 2px;font-size:13px;color:#cbd5e1;
}

/* Peeking White Table Header inside Bottom of Midnight Stage */
.table-peek-head{
  background:var(--white);
  color:var(--head-gray);
  border-radius:16px 16px 0 0;
  border:1px solid var(--line);
  border-bottom:2px solid #cbd5e1;
  box-shadow:0 -12px 34px rgba(3,10,24,.28);
  padding:18px 24px;
}
.peek-top{
  display:flex;justify-content:space-between;align-items:center;
  gap:16px;flex-wrap:wrap;
  padding-bottom:12px;margin-bottom:12px;
  border-bottom:1px solid var(--line);
  font-size:13px;color:var(--head-gray);
}
.peek-cols{
  display:grid;
  grid-template-columns:1.1fr 1.6fr 1.5fr 1fr;
  gap:16px;
  font-size:13px;font-weight:800;
  color:var(--head-gray);
  letter-spacing:.2px;
}

/* White Table Body Section right below Midnight Stage */
.table-sheet-section{
  padding:0 0 64px;
}
.table-sheet{
  background:var(--white);
  border:1px solid var(--line);
  border-top:none;
  border-radius:0 0 16px 16px;
  box-shadow:0 16px 40px rgba(15,23,42,.06);
  overflow:hidden;
}
.sheet-row{
  display:grid;
  grid-template-columns:1.1fr 1.6fr 1.5fr 1fr;
  gap:16px;
  padding:18px 24px;
  border-bottom:1px solid var(--line);
  align-items:center;
  font-size:14px;
}
.sheet-row:last-child{border-bottom:none}
.sheet-row:hover{background:#f8fafc}
.col-title{font-weight:700;color:var(--ink)}
.col-sub{display:block;font-size:12px;color:var(--mute);margin-top:2px}
.sample-box{
  background:#f8fafc;border:1px solid var(--line);
  border-radius:8px;padding:8px 10px;font-size:13px;color:#334155;
}
.pill{
  display:inline-block;padding:4px 10px;border-radius:999px;
  font-size:12px;font-weight:700;
  background:#eff6ff;color:#1d4ed8;
}

/* Standard Sections */
.section{padding:76px 0}
.section-alt{background:var(--white);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.sec-head{max-width:720px;margin-bottom:36px}
.sec-kicker{
  display:inline-block;font-size:12px;font-weight:800;
  color:var(--accent);letter-spacing:1.4px;text-transform:uppercase;
}
.sec-head h2{
  font-size:clamp(26px,3.6vw,40px);
  margin:8px 0 12px;line-height:1.2;color:var(--ink);
}
.sec-head p{margin:0;color:var(--mute)}

/* 6 Cards Grid (3x2) */
.grid-6{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:20px;
}
.card{
  background:var(--white);
  border:1px solid var(--line);
  border-radius:14px;
  padding:24px;
  box-shadow:0 4px 14px rgba(15,23,42,.03);
}
.section-alt .card{background:#f8fafc}
.card-tag{
  display:inline-flex;align-items:center;justify-content:center;
  width:38px;height:38px;border-radius:10px;
  background:#eff6ff;color:var(--accent);
  font-weight:800;font-size:15px;margin-bottom:14px;
}
.card h3{margin:0 0 8px;font-size:18px;color:var(--ink)}
.card p{margin:0;color:var(--mute);font-size:14px}

/* Split showcase with images */
.split-showcase{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:36px;
  align-items:center;
  margin-top:36px;
}
.frame{
  background:var(--white);
  border:1px solid var(--line);
  border-radius:14px;
  padding:12px;
  box-shadow:0 12px 30px rgba(15,23,42,.06);
}
.frame img{border-radius:10px;width:100%;aspect-ratio:16/10;object-fit:cover}

/* User Reviews */
.review-meta{
  display:flex;align-items:center;gap:12px;margin-top:16px;
  padding-top:14px;border-top:1px solid var(--line);
}
.avatar{
  width:38px;height:38px;border-radius:50%;
  display:grid;place-items:center;
  background:var(--midnight);color:#fff;font-weight:800;font-size:14px;
}
.review-meta b{display:block;font-size:14px;color:var(--ink)}
.review-meta small{color:var(--mute);font-size:12px}

/* FAQ */
.faq-list{display:grid;gap:12px}
.faq-item{
  background:var(--white);
  border:1px solid var(--line);
  border-radius:12px;
  padding:4px 20px;
}
.faq-item summary{
  padding:14px 0;
  font-weight:700;color:var(--ink);
  cursor:pointer;list-style:none;
  display:flex;justify-content:space-between;align-items:center;
}
.faq-item summary::after{content:"+";font-size:18px;color:var(--accent)}
.faq-item[open] summary::after{content:"−"}
.faq-item p{margin:0 0 16px;color:var(--mute);font-size:14px}

/* Help Layout */
.help-grid{
  display:grid;
  grid-template-columns:240px 1fr;
  gap:28px;
  align-items:start;
}
.help-menu{
  position:sticky;top:92px;
  background:var(--white);
  border:1px solid var(--line);
  border-radius:12px;
  padding:14px;
}
.help-menu a{
  display:block;padding:9px 12px;border-radius:8px;
  font-size:14px;color:var(--head-gray);font-weight:600;
}
.help-menu a:hover{background:#f1f5f9;color:var(--accent)}
.help-block{
  background:var(--white);
  border:1px solid var(--line);
  border-radius:14px;
  padding:26px;
  margin-bottom:20px;
}
.help-block h2{margin:0 0 12px;font-size:22px}
.help-block p{color:var(--mute);margin:0 0 12px}

/* Footer */
.site-footer{
  background:var(--midnight);
  color:#cbd5e1;
  padding:56px 0 28px;
}
.footer-grid{
  display:grid;
  grid-template-columns:1.4fr repeat(3,1fr);
  gap:28px;
  padding-bottom:32px;
  border-bottom:1px solid var(--dark-line);
}
.footer-grid h4{margin:0 0 12px;color:#fff;font-size:15px}
.footer-grid a{display:block;margin:8px 0;font-size:14px;color:#94a3b8}
.footer-grid a:hover{color:#fff}
.footer-bottom{
  padding-top:20px;
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;
  font-size:13px;color:#94a3b8;
}

@media (max-width:920px){
  .nav-links{display:none}
  .hero-grid,.split-showcase,.help-grid,.footer-grid{grid-template-columns:1fr}
  .grid-6{grid-template-columns:repeat(2,1fr)}
  .peek-cols,.sheet-row{grid-template-columns:1fr 1fr;gap:10px}
  .help-menu{position:static}
}
@media (max-width:560px){
  .grid-6,.peek-cols,.sheet-row{grid-template-columns:1fr}
}

/* PERF-OPTIMIZED: 硬件加速与防卡顿渲染优化 */
.site-nav,.topbar,.header,.fixed-mid-ribbon{
  -webkit-backdrop-filter:blur(10px);
  transform:translateZ(0);
  will-change:transform;
}
#features,#scenes,#reviews,#faq,#packages,#install,#privacy,.site-footer{
  content-visibility:auto;
  contain-intrinsic-size:1px 620px;
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms !important;transition-duration:.01ms !important}
}