:root{
  color-scheme:dark;
  --bg:#08090A;
  --panel:#101314;
  --panel-live:#141A18;
  --line:#1C2022;
  --ink:#E7EAEA;
  --muted:#757C7F;
  --wire:#2B3133;
  --live:#5FD39B;
  --hot:#C4564E;
  --mono:"JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;
  --sans:"Instrument Sans","Segoe UI",system-ui,sans-serif;
  box-sizing:border-box;
  padding-top:env(safe-area-inset-top,0px);
  padding-bottom:env(safe-area-inset-bottom,0px);
}
*,*::before,*::after{box-sizing:inherit}
html,body{height:100%}
html{background:var(--bg)}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font:15px/1.6 var(--sans);-webkit-font-smoothing:antialiased;
  display:flex;flex-direction:column;align-items:center;
  padding:22px 16px 28px;
}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--live);outline-offset:2px;border-radius:4px}
button{font:inherit;color:inherit}

/* header */
.top{width:min(100%,540px);display:flex;align-items:center;justify-content:space-between;gap:12px}
.brand{font:500 13px/1 var(--mono);color:var(--muted)}
.brand span{color:var(--ink)}
.ghost{font:500 12px/1 var(--mono);background:none;border:1px solid var(--line);color:var(--muted);padding:7px 10px;border-radius:7px;cursor:pointer;transition:color .15s,border-color .15s}
.ghost:hover{color:var(--ink);border-color:var(--wire)}
.ghost[aria-pressed="false"]{opacity:.6}

.app{width:min(100%,540px);margin-top:26px}

/* hud */
.hud{display:flex;gap:26px;margin-bottom:14px}
.hud .stat:last-child{margin-left:auto}
.stat{display:flex;flex-direction:column;gap:4px}
.stat .k{font:400 11px/1 var(--mono);color:var(--muted);letter-spacing:.04em}
.stat .v{font:500 17px/1 var(--mono);font-variant-numeric:tabular-nums}
.stat .v i{font-style:normal;font-size:12px;color:var(--muted)}

/* trace */
.trace{margin-bottom:18px}
.trace-head{display:flex;justify-content:space-between;font:400 11px/1 var(--mono);color:var(--muted);margin-bottom:6px}
.trace-head span:last-child{font-variant-numeric:tabular-nums}
.bar{height:3px;background:var(--line);border-radius:2px;overflow:hidden}
.bar i{display:block;height:100%;width:0;background:var(--muted);transition:width .18s linear,background .4s}
.trace.warn .bar i{background:var(--hot)}
.trace.warn .trace-head span:last-child{color:var(--hot)}

/* board */
.board-wrap{position:relative}
.board{
  display:grid;grid-template-columns:repeat(var(--n,5),1fr);
  gap:2px;padding:2px;aspect-ratio:1;
  background:var(--line);border-radius:10px;overflow:hidden;
}
.cell{
  position:relative;appearance:none;border:0;padding:0;margin:0;
  background:var(--panel);cursor:pointer;display:block;
  transition:background .25s;
}
.cell svg{display:block;width:100%;height:100%;rotate:0deg;transition:rotate .2s cubic-bezier(.3,1.35,.5,1)}
.wire line{stroke:var(--wire);stroke-width:9;stroke-linecap:round;transition:stroke .2s}
.core{fill:none;stroke:var(--wire);stroke-width:8;transition:stroke .2s,fill .2s}
.core-in{fill:var(--bg);stroke:none}
.cell.on{background:var(--panel-live)}
.cell.on .wire line,.cell.on .core{stroke:var(--live)}
.cell.on .core.term,.cell.on .core.server{fill:var(--live)}
.cell.on svg{filter:drop-shadow(0 0 5px rgba(95,211,155,.35))}
.cell.locked{cursor:not-allowed;background:
  repeating-linear-gradient(135deg,var(--panel) 0 6px,#0B0E0F 6px 12px)}
.cell.loud::after{
  content:"";position:absolute;inset:0;background:var(--hot);opacity:.28;
  animation:loud .45s ease-out forwards;pointer-events:none;
}
@keyframes loud{to{opacity:0}}
.cell.nope svg{animation:nope .25s ease}
@keyframes nope{25%{translate:-3px 0}75%{translate:3px 0}}
.board.done .cell.on svg{filter:drop-shadow(0 0 9px rgba(95,211,155,.6))}

/* overlay */
.overlay{position:absolute;inset:0;display:grid;place-items:center;padding:14px;
  background:rgba(8,9,10,.86);backdrop-filter:blur(3px);border-radius:10px;z-index:2}
.card{width:100%;max-width:340px;text-align:left}
.card h1{margin:0 0 10px;font:700 20px/1.2 var(--mono);letter-spacing:-.01em}
.card h1.bad{color:var(--hot)}
.card h1.good{color:var(--live)}
.card p{margin:0 0 14px;color:var(--muted);font-size:14px}
.rules{margin:0 0 18px;padding:0;list-style:none;display:flex;flex-direction:column;gap:8px}
.rules li{font:400 12.5px/1.55 var(--mono);color:var(--muted);padding-left:14px;position:relative}
.rules li::before{content:"·";position:absolute;left:2px;color:var(--wire)}
.rules b{color:var(--ink);font-weight:500}
.score-rows{margin:0 0 18px;font:400 12.5px/1.9 var(--mono);color:var(--muted)}
.score-rows div{display:flex;justify-content:space-between}
.score-rows b{color:var(--ink);font-weight:500;font-variant-numeric:tabular-nums}
.btn{background:var(--ink);color:var(--bg);border:0;border-radius:8px;
  font:600 14px/1 var(--sans);padding:12px 20px;cursor:pointer;transition:opacity .15s}
.btn:hover{opacity:.85}

.hint{margin:16px 0 0;font:400 11.5px/1.7 var(--mono);color:var(--muted);text-align:center}
.foot{margin-top:auto;padding-top:34px;font:400 11px/1 var(--mono);color:#43494B}

@media (max-width:600px){
  *,*::before,*::after{animation:none!important;transition:none!important}
  body{padding:16px 12px 20px}
  .app{margin-top:20px}
  .hud{gap:18px}
  .stat .v{font-size:15px}
  .cell.on svg,.board.done .cell.on svg{filter:none}
  .hint{font-size:11px}
}
@media (prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important}
}