:root{
  --bg-deep:#070f0c;
  --panel-border:rgba(130,210,180,0.16);
  --snake-head:#5fe89a;
  --snake-mid:#2fa968;
  --gold:#ffcb57;
  --teal:#5fe8d0;
  --text-primary:#eef7f0;
  --text-muted:#7fa08e;
  --text-faint:#4f6b5e;
  --radius-lg:clamp(14px, 2.2vmin, 28px);
  --radius-md:clamp(12px, 1.6vmin, 16px);
  --radius-sm:clamp(9px, 1.2vmin, 12px);
  --radius-pill:999px;
  --shadow-deep:0 16px 40px rgba(0,0,0,0.5);
  --layout-max:1480px;
  --font-ui:"Noto Sans","PingFang SC","PingFang TC","PingFang HK","Hiragino Sans","Hiragino Sans GB","Microsoft YaHei","Microsoft JhengHei","Noto Sans Arabic","Noto Sans Hebrew","Noto Sans Devanagari","Noto Sans Thai",sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Consolas,monospace;
  color-scheme:dark;
}
*{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent;-webkit-touch-callout:none;}
html,body{
  height:100%;
  overflow:hidden;
  overscroll-behavior:none;
  background:var(--bg-deep);
}
body{
  position:fixed;
  inset:0;
  width:100%;
  color:var(--text-primary);
  font-family:var(--font-ui);
  touch-action:manipulation;
  -webkit-user-select:none;
  user-select:none;
}
button{font-family:inherit;border:none;background:none;color:inherit;cursor:pointer;appearance:none;-webkit-appearance:none;}
button:disabled{cursor:default;opacity:0.45;}
button:focus-visible{outline:2px solid var(--teal);outline-offset:2px;border-radius:6px;}
svg{display:block;}
@media (min-width:1800px){
  :root{--layout-max:1760px;}
}
@media (min-width:2400px){
  :root{--layout-max:2100px;}
}