:root{
  --bg:#05060a;
  --fg:#e9ecf2;
  --dim:#7b8496;
  --faint:#4a5261;
  --line:rgba(255,255,255,.09);
  --panel:rgba(255,255,255,.045);
  --accent:#22d3ee;
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;
}

*{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent}

html,body{
  height:100%;
  overflow:hidden;
  background:var(--bg);
  color:var(--fg);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}

body{
  overscroll-behavior:none;
  touch-action:none;
  user-select:none;
  -webkit-user-select:none;
  -webkit-touch-callout:none;
}

#stage{
  position:fixed;
  inset:0;
  width:100%;
  height:100%;
  display:block;
  touch-action:none;
}

/* ---------- HUD ---------- */

.hud{
  position:fixed;
  inset:0;
  z-index:10;
  display:flex;
  flex-direction:column;
  padding:calc(env(safe-area-inset-top,0px) + 18px) 20px calc(env(safe-area-inset-bottom,0px) + 16px);
  pointer-events:none;
}

.top{display:flex;align-items:center;justify-content:space-between}

.brand{
  display:flex;align-items:center;gap:9px;
  font-size:11px;font-weight:600;letter-spacing:.22em;color:var(--dim);
}
.brand i{
  width:6px;height:6px;border-radius:50%;
  background:var(--accent);
  box-shadow:0 0 12px var(--accent);
}

.counter{font-family:var(--mono);font-size:12px;color:var(--dim);letter-spacing:.06em}
.counter b{color:var(--fg);font-size:14px;font-weight:500}
.counter s{text-decoration:none;opacity:.35;margin:0 3px}
.counter em{font-style:normal}

.info{
  margin-top:26px;
  max-width:min(80%,350px);
  transition:opacity .34s ease,transform .34s ease;
}
.info.swap{opacity:0;transform:translateY(7px)}
.info h1{font-size:22px;font-weight:500;line-height:1.25;letter-spacing:.01em}
.info p{margin-top:7px;font-size:13px;line-height:1.62;color:var(--dim)}

.foot{
  margin-top:auto;
  display:flex;
  flex-direction:column;
  gap:12px;
}

.ctrls{display:flex;gap:8px;pointer-events:auto}
.ctrls:empty{display:none}
.ctrls button{
  font:inherit;font-size:12px;color:var(--fg);
  background:var(--panel);
  border:1px solid var(--line);
  padding:8px 15px;border-radius:100px;
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
}
.ctrls button:active{background:rgba(255,255,255,.15)}

.nav{
  display:flex;gap:5px;
  width:100%;
  padding:5px;
  border-radius:100px;
  background:var(--panel);
  border:1px solid var(--line);
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  pointer-events:auto;
}
.nav button{
  flex:1;
  display:flex;flex-direction:column;align-items:center;gap:3px;
  font:inherit;font-size:12px;line-height:1.2;
  color:var(--dim);
  background:transparent;border:0;
  padding:9px 2px;border-radius:100px;
  transition:color .2s ease,background .25s ease;
}
.nav button .n{font-family:var(--mono);font-size:9px;letter-spacing:.08em;opacity:.5}
.nav button.on{background:rgba(255,255,255,.1);color:var(--fg)}
.nav button.on .n{opacity:1;color:var(--accent)}

/* ---------- toast ---------- */

.toast{
  position:fixed;left:50%;
  bottom:calc(env(safe-area-inset-bottom,0px) + 136px);
  z-index:20;
  transform:translate(-50%,9px);
  padding:9px 18px;
  border-radius:100px;
  font-size:12px;color:var(--fg);white-space:nowrap;
  background:rgba(20,25,34,.84);
  border:1px solid var(--line);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  opacity:0;
  transition:opacity .38s ease,transform .38s ease;
  pointer-events:none;
}
.toast.show{opacity:1;transform:translate(-50%,0)}

/* ---------- intro ---------- */

.intro{
  position:fixed;inset:0;z-index:30;
  display:flex;align-items:center;justify-content:center;
  padding:36px 26px;
  background:
    radial-gradient(130% 80% at 50% -10%,rgba(18,32,60,.72) 0%,rgba(5,6,10,.86) 64%);
  transition:opacity .62s ease,visibility .62s ease;
  pointer-events:auto;
}
.intro.hide{opacity:0;visibility:hidden;pointer-events:none}

.intro-box{width:100%;max-width:430px}

.kicker{
  font-family:var(--mono);
  font-size:10.5px;letter-spacing:.2em;
  color:var(--accent);opacity:.85;
  margin-bottom:20px;
}

.intro-box h1{
  font-size:clamp(26px,7.6vw,34px);
  font-weight:500;line-height:1.3;letter-spacing:-.01em;
}

.intro-box p{
  margin-top:17px;
  font-size:14px;line-height:1.78;color:var(--dim);
}

#go{
  margin-top:36px;
  font:inherit;font-size:15px;font-weight:500;letter-spacing:.06em;
  color:#03141b;
  background:linear-gradient(135deg,#7df0ff 0%,#22d3ee 100%);
  border:0;padding:16px 36px;border-radius:100px;
  box-shadow:0 10px 34px -10px rgba(34,211,238,.65);
  transition:transform .15s ease,box-shadow .25s ease;
}
#go:active{
  transform:translateY(1px) scale(.985);
  box-shadow:0 5px 20px -8px rgba(34,211,238,.55);
}

.intro-foot{margin-top:22px;font-size:11px;color:var(--faint);letter-spacing:.05em}

/* ---------- short screens ---------- */

@media (max-height:540px){
  .info{margin-top:14px}
  .info h1{font-size:18px}
  .info p{display:none}
  .toast{bottom:calc(env(safe-area-inset-bottom,0px) + 112px)}
}