:root {
  --bg: #f6f7f9;
  --panel: #ffffff;
  --text: #1c2026;
  --muted: #5b6573;
  --line: #d5dae1;
  --accent: #1f6feb;
  --accent-text: #ffffff;
  --code-bg: #fbfcfd;
  --danger: #b42318;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1216;
    --panel: #171b21;
    --text: #e6e9ee;
    --muted: #9aa5b4;
    --line: #2b323c;
    --accent: #4c8dff;
    --accent-text: #0b1020;
    --code-bg: #12161b;
    --danger: #ff7b72;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
header, main, footer { max-width: 1280px; margin: 0 auto; padding: 0 16px; }
header { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 16px; padding-top: 20px; }
h1 { font-size: 1.4rem; margin: 0; }
h2 { font-size: 0.95rem; margin: 12px 0 6px; color: var(--muted); font-weight: 600; letter-spacing: 0.02em; }
.tagline { margin: 0; color: var(--muted); }
.build { margin: 0; color: var(--muted); font: 0.8rem ui-monospace, "SF Mono", Menlo, Consolas, monospace; }
nav { margin-left: auto; }
main { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.25fr); gap: 16px; margin-top: 12px; }
@media (max-width: 860px) { main { grid-template-columns: minmax(0, 1fr); } }
.panel { background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 4px 14px 14px; }
.toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 8px 0; }
.spacer { flex: 1; }
label { display: inline-flex; align-items: center; gap: 6px; font-size: 0.9rem; color: var(--muted); }
select, button, input, textarea { font: inherit; color: var(--text); }
select, input {
  background: var(--code-bg); border: 1px solid var(--line); border-radius: 6px; padding: 5px 8px;
}
button {
  background: var(--code-bg); border: 1px solid var(--line); border-radius: 6px; padding: 5px 12px; cursor: pointer;
}
button:hover:not(:disabled) { border-color: var(--accent); }
button:disabled { opacity: 0.5; cursor: not-allowed; }
#run { background: var(--accent); color: var(--accent-text); border-color: var(--accent); font-weight: 600; }
kbd { font: 0.75rem ui-monospace, monospace; opacity: 0.8; margin-left: 4px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
textarea {
  width: 100%; min-height: 280px; resize: vertical; padding: 10px;
  background: var(--code-bg); border: 1px solid var(--line); border-radius: 6px;
  font: 0.9rem/1.45 ui-monospace, "SF Mono", Menlo, Consolas, monospace; tab-size: 2;
}
#repl { display: flex; align-items: center; gap: 8px; margin-top: 8px; }
#repl input { flex: 1; font: 0.9rem ui-monospace, "SF Mono", Menlo, Consolas, monospace; }
.prompt { font: 1rem ui-monospace, monospace; color: var(--muted); }
.stage { background: #000; border-radius: 6px; overflow: hidden; line-height: 0; }
#stage { width: 100%; height: auto; display: block; image-rendering: auto; }
#stage:focus-visible { outline: 3px solid var(--accent); outline-offset: -3px; }
#log {
  margin: 0; min-height: 5.5em; max-height: 14em; overflow: auto; padding: 8px 10px; white-space: pre-wrap;
  background: var(--code-bg); border: 1px solid var(--line); border-radius: 6px;
  font: 0.85rem/1.4 ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}
#log .err { color: var(--danger); }
#log .cmd { color: var(--muted); }
#status { font-size: 0.9rem; color: var(--muted); }
footer { padding-bottom: 28px; color: var(--muted); font-size: 0.85rem; }
.sr-only { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }