:root{
  --bg:#0a0e1a;
  --bg-soft:#111726;
  --panel:#141c2e;
  --line:#223049;
  --text:#e7eefc;
  --muted:#8da2c0;
  --c1:#36e0c8;
  --c2:#2f8bff;
  --c3:#7c5cff;
  --radius:16px;
  --shadow:0 18px 50px rgba(0,0,0,.45);
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:"Microsoft YaHei","PingFang SC","Noto Sans CJK SC",system-ui,sans-serif;
  background:var(--bg);
  color:var(--text);
  line-height:1.7;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}

/* ===== 导航 ===== */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:100;
  transition:background .35s ease, box-shadow .35s ease, backdrop-filter .35s;
}
.nav.scrolled{
  background:rgba(10,14,26,.82);
  backdrop-filter:blur(12px);
  box-shadow:0 6px 24px rgba(0,0,0,.4);
  border-bottom:1px solid var(--line);
}
.nav-inner{
  max-width:1180px;margin:0 auto;padding:14px 24px;
  display:flex;align-items:center;gap:18px;
}
.brand{display:flex;align-items:center;gap:10px;font-size:20px;font-weight:600}
.brand-text b{color:var(--c1);font-weight:800}
.brand-mark{display:flex;filter:drop-shadow(0 0 10px rgba(54,224,200,.4))}
.nav-links{display:flex;gap:26px;list-style:none;margin-left:auto;font-size:15px}
.nav-links a{color:var(--muted);transition:color .2s}
.nav-links a:hover{color:var(--text)}
.nav-cta{
  margin-left:8px;padding:9px 18px;border-radius:999px;font-size:14px;font-weight:600;
  background:linear-gradient(135deg,var(--c1),var(--c2));color:#04121f;
  transition:transform .2s, box-shadow .2s;
}
.nav-cta:hover{transform:translateY(-2px);box-shadow:0 10px 24px rgba(47,139,255,.4)}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;margin-left:auto}
.nav-toggle span{width:24px;height:2px;background:var(--text);border-radius:2px;transition:.3s}

/* ===== Hero ===== */
.hero{position:relative;padding:160px 24px 90px;overflow:hidden}
.hero-bg{
  position:absolute;inset:-20% -10% auto -10%;height:120%;
  background:
    radial-gradient(60% 50% at 20% 10%,rgba(54,224,200,.18),transparent 60%),
    radial-gradient(55% 50% at 85% 20%,rgba(47,139,255,.20),transparent 60%),
    radial-gradient(50% 60% at 50% 100%,rgba(124,92,255,.16),transparent 60%);
  filter:blur(8px);
  animation:floatBg 14s ease-in-out infinite alternate;
}
@keyframes floatBg{from{transform:translateY(-12px) scale(1)}to{transform:translateY(12px) scale(1.04)}}
.hero-inner{position:relative;max-width:1080px;margin:0 auto;text-align:center}
.hero-eyebrow{
  display:inline-block;padding:6px 16px;border:1px solid var(--line);border-radius:999px;
  color:var(--c1);font-size:14px;letter-spacing:.5px;margin-bottom:22px;
  background:rgba(54,224,200,.06);
}
.hero-title{font-size:clamp(38px,7vw,72px);line-height:1.12;font-weight:800;letter-spacing:1px}
.grad{background:linear-gradient(120deg,var(--c1),var(--c2) 50%,var(--c3));-webkit-background-clip:text;background-clip:text;color:transparent}
.hero-sub{max-width:720px;margin:22px auto 0;color:var(--muted);font-size:18px}
.hero-sub b{color:var(--text)}
.hero-actions{display:flex;gap:16px;justify-content:center;margin-top:34px;flex-wrap:wrap}

.btn{display:inline-block;padding:13px 30px;border-radius:12px;font-size:16px;font-weight:600;transition:transform .2s,box-shadow .2s,background .2s}
.btn-primary{background:linear-gradient(135deg,var(--c1),var(--c2));color:#04121f;box-shadow:0 12px 30px rgba(47,139,255,.35)}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 16px 40px rgba(47,139,255,.5)}
.btn-ghost{border:1px solid var(--line);color:var(--text);background:rgba(255,255,255,.02)}
.btn-ghost:hover{border-color:var(--c1);color:var(--c1)}

/* ===== 代码窗口 ===== */
.code-window{
  max-width:680px;margin:54px auto 0;text-align:left;
  background:linear-gradient(180deg,#0d1424,#0a1020);
  border:1px solid var(--line);border-radius:14px;overflow:hidden;
  box-shadow:var(--shadow);
  opacity:0;transform:translateY(30px);transition:opacity .8s ease,transform .8s ease;
}
.code-window.in{opacity:1;transform:none}
.code-window.wide{max-width:820px;margin-top:40px}
.code-bar{display:flex;align-items:center;gap:8px;padding:12px 16px;background:#0b1220;border-bottom:1px solid var(--line)}
.dot{width:11px;height:11px;border-radius:50%}
.dot.r{background:#ff5f57}.dot.y{background:#febc2e}.dot.g{background:#28c840}
.code-name{margin-left:10px;color:var(--muted);font-size:13px;font-family:"Cascadia Code",Consolas,monospace}
.code-body{padding:22px 24px;font-family:"Cascadia Code",Consolas,monospace;font-size:15px;line-height:1.85;color:#cfe0ff;min-height:230px;white-space:pre-wrap;word-break:break-all}
#typewriter{color:#d6e6ff}
.typed-cursor{display:inline-block;width:9px;height:18px;background:var(--c1);vertical-align:-3px;animation:blink 1s steps(2) infinite}
@keyframes blink{50%{opacity:0}}
.kw{color:#7c5cff;font-weight:600}
.str{color:#36e0c8}

/* ===== 数据条 ===== */
.stats{
  max-width:1080px;margin:10px auto;padding:40px 24px;
  display:grid;grid-template-columns:repeat(4,1fr);gap:20px;
}
.stat{text-align:center;background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:28px 12px}
.stat-num{font-size:clamp(30px,4vw,46px);font-weight:800;background:linear-gradient(120deg,var(--c1),var(--c2));-webkit-background-clip:text;background-clip:text;color:transparent}
.stat-label{color:var(--muted);margin-top:6px;font-size:14px}

/* ===== 通用 section ===== */
.section-head{max-width:760px;margin:0 auto 44px;text-align:center}
.section-head h2{font-size:clamp(26px,4vw,40px);font-weight:800}
.section-head p{color:var(--muted);margin-top:12px;font-size:17px}

.features,.corelib,.demo,.download{padding:84px 24px}
.features{max-width:1180px;margin:0 auto}
.feature-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.card{
  background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 22px;transition:transform .25s ease,box-shadow .25s ease,border-color .25s;
  opacity:0;transform:translateY(28px);
}
.card.in{opacity:1;transform:none}
.card:hover{transform:translateY(-6px);border-color:var(--c1);box-shadow:0 16px 40px rgba(47,139,255,.18)}
.card-icon{
  width:52px;height:52px;border-radius:14px;display:flex;align-items:center;justify-content:center;
  font-size:24px;font-weight:800;margin-bottom:16px;
  background:linear-gradient(135deg,rgba(54,224,200,.18),rgba(47,139,255,.18));
  color:var(--c1);border:1px solid var(--line);
}
.card h3{font-size:18px;margin-bottom:8px}
.card p{color:var(--muted);font-size:14.5px}

/* ===== 核心库 ===== */
.corelib{background:var(--bg-soft)}
.lib-grid{max-width:1080px;margin:0 auto;display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.lib-item{
  background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:18px 20px;
  font-size:15px;color:var(--text);transition:transform .2s,border-color .2s;
  opacity:0;transform:translateY(24px);
}
.lib-item.in{opacity:1;transform:none}
.lib-item:hover{transform:translateX(6px);border-color:var(--c2)}
.lib-tag{
  display:inline-block;margin-right:10px;padding:3px 10px;border-radius:8px;font-size:13px;font-weight:600;
  background:linear-gradient(135deg,rgba(124,92,255,.22),rgba(47,139,255,.22));color:#cdbcff;
}

/* ===== 下载 ===== */
.download{max-width:1180px;margin:0 auto}
.download-card{
  background:linear-gradient(135deg,rgba(54,224,200,.10),rgba(47,139,255,.12));
  border:1px solid var(--line);border-radius:24px;padding:60px 30px;text-align:center;
}
.download-card h2{font-size:clamp(24px,3.5vw,36px);font-weight:800}
.download-card p{color:var(--muted);margin-top:14px;font-size:17px}
.dl-actions{display:flex;gap:16px;justify-content:center;margin-top:30px;flex-wrap:wrap}
.dl-note{margin-top:24px;color:var(--muted);font-size:13px}

/* ===== 页脚 ===== */
.footer{border-top:1px solid var(--line);padding:46px 24px;background:var(--bg-soft)}
.footer-inner{max-width:1080px;margin:0 auto;text-align:center}
.footer-brand{font-size:22px;font-weight:700}
.footer-brand b{color:var(--c1)}
.footer p{color:var(--muted);margin-top:8px;font-size:14px}
.copy{margin-top:18px;font-size:13px;opacity:.8}
.copy a{color:var(--c1);text-decoration:none}
.copy a:hover{text-decoration:underline}

/* ===== 响应式 ===== */
@media (max-width:980px){
  .feature-grid{grid-template-columns:repeat(2,1fr)}
  .lib-grid{grid-template-columns:repeat(2,1fr)}
  .stats{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:680px){
  .nav-links{
    position:absolute;top:62px;left:0;right:0;flex-direction:column;gap:0;
    background:rgba(10,14,26,.97);border-bottom:1px solid var(--line);
    max-height:0;overflow:hidden;transition:max-height .3s;
  }
  .nav-links.open{max-height:420px}
  .nav-links li{padding:14px 24px;border-top:1px solid var(--line)}
  .nav-cta{display:none}
  .nav-toggle{display:flex}
  .feature-grid,.lib-grid,.stats{grid-template-columns:1fr}
  .hero{padding-top:130px}
}