:root {
  --bg: #f6f7f9; --card: #ffffff; --text: #1b1f24; --muted: #5b6470; --line: #dde1e6;
  --accent: #1f5fbf; --ok: #1f7a4d; --err: #b3261e; --warn-bg: #fff6e0; --warn-line: #e8c26a;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #111418; --card: #1a1e24; --text: #e7eaee; --muted: #9aa3ad; --line: #2c323a;
          --accent: #6ea2ff; --ok: #4cc38a; --err: #ff8a80; --warn-bg: #2b2414; --warn-line: #7a6223; }
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; background: var(--bg); color: var(--text);
       font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
main { max-width: 640px; margin: 0 auto; padding: 32px 16px 64px; }
h1 { font-size: 1.4rem; margin: 0 0 4px; }
.sub { color: var(--muted); margin: 0 0 24px; font-size: .95rem; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 20px; margin-bottom: 16px; }
ol.steps { list-style: none; padding: 0; margin: 16px 0 0; }
ol.steps li { display: grid; grid-template-columns: 24px 1fr; gap: 0 10px; padding: 8px 0; border-top: 1px solid var(--line); }
ol.steps li:first-child { border-top: 0; }
ol.steps li::before { content: "○"; color: var(--muted); grid-row: span 2; font-weight: 700; }
ol.steps li[data-state="doing"]::before { content: "◔"; color: var(--accent); }
ol.steps li[data-state="done"]::before { content: "✓"; color: var(--ok); }
ol.steps li[data-state="error"]::before { content: "✕"; color: var(--err); }
.label { font-weight: 600; }
.detail { color: var(--muted); font-size: .9rem; min-height: 0; }
button, .button { display: inline-block; font: inherit; font-weight: 600; padding: 10px 18px; border-radius: 8px;
                  border: 1px solid var(--accent); background: var(--accent); color: #fff; cursor: pointer; text-decoration: none; }
button.secondary { background: transparent; color: var(--accent); }
button:disabled { opacity: .5; cursor: default; }
.error { color: var(--err); font-weight: 600; margin-top: 12px; }
.warn { background: var(--warn-bg); border: 1px solid var(--warn-line); border-radius: 8px; padding: 10px 12px; font-size: .92rem; }
canvas { display: block; margin: 16px auto; max-width: 100%; height: auto; image-rendering: pixelated; border-radius: 6px; }
pre { background: var(--bg); border: 1px solid var(--line); border-radius: 8px; padding: 12px; overflow-x: auto;
      font-size: .8rem; white-space: pre; }
.actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 12px; }
footer { color: var(--muted); font-size: .8rem; text-align: center; margin-top: 24px; }