:root {
    --ink: #0a0e14;
    --text: #e6edf3;
    --dim: #8b96a3;
    --rule: #2a3340;
    --amber: #f59e0b;
    --text-body: 14px;
    --text-micro: 11px;
  }
  * { box-sizing: border-box; margin: 0; padding: 0; border-radius: 0; }
  html, body { height: 100%; background: var(--ink); color: var(--text); overflow: hidden; }
  body { font: 400 var(--text-body)/1.4 "Source Sans 3", system-ui, sans-serif; }
  canvas { display: block; position: fixed; inset: 0; width: 100%; height: 100%; }
  header {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1;
    display: flex; align-items: center; justify-content: space-between; gap: 16px;
    padding: max(12px, env(safe-area-inset-top)) 16px 12px;
    border-bottom: 1px solid var(--rule);
    background: var(--ink);
  }
  .mark { font: 400 var(--text-micro)/1 "JetBrains Mono", monospace; letter-spacing: .12em; text-transform: uppercase; color: var(--dim); }
  .mark b { color: var(--text); font-weight: 400; }
  #enter {
    font: 400 var(--text-micro)/1 "JetBrains Mono", monospace; letter-spacing: .12em; text-transform: uppercase;
    color: var(--ink); background: var(--amber); border: 0; padding: 10px 14px; min-height: 36px; cursor: pointer;
  }
  #enter[hidden] { display: none; }
  .tool { font: 400 var(--text-micro)/1 "JetBrains Mono", monospace; letter-spacing: .12em; text-transform: uppercase;
    color: var(--text); background: none; border: 1px solid var(--rule); padding: 9px 12px; min-height: 36px; cursor: pointer; }
  .tool:hover, .tool:focus-visible { border-color: var(--amber); outline: none; }
  .back { font: 400 var(--text-micro)/1 "JetBrains Mono", monospace; letter-spacing: .12em; text-transform: uppercase; color: var(--dim); text-decoration: none; padding: 10px 0; }
  .back:hover, .back:focus-visible { color: var(--amber); outline: none; }
  .note { position: fixed; left: 0; bottom: 0; z-index: 1; max-width: 65ch; padding: 8px 16px max(8px, env(safe-area-inset-bottom));
    background: var(--ink); border-top: 1px solid var(--rule); border-right: 1px solid var(--rule);
    font: 400 var(--text-micro)/1.5 "JetBrains Mono", monospace; color: var(--dim); pointer-events: none; }
  #enter:focus-visible { outline: 2px solid var(--text); outline-offset: 2px; }
  /* Real links: screen readers, no-WebGL, and anyone who would rather tap a list. */
  nav { position: fixed; left: 0; right: 0; bottom: 0; z-index: 1; display: flex; flex-wrap: wrap; gap: 4px 16px;
    padding: 10px 16px max(10px, env(safe-area-inset-bottom)); border-top: 1px solid var(--rule); background: var(--ink); }
  nav a { font: 400 var(--text-micro)/1 "JetBrains Mono", monospace; letter-spacing: .08em; color: var(--dim); text-decoration: none; padding: 8px 0; }
  nav a:hover, nav a:focus-visible { color: var(--amber); outline: none; }