:root {
  --bg: #fafaf8; --panel: #ffffff; --ink: #1d1d1f; --muted: #6b6b70; --line: #dedee3;
  --accent: #1f6f78; --accent-ink: #ffffff; --good: #2f7d4a;
  --square: #9dc3e6; --tilted: #f0a35e; --edge: #3a3a40;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #131315; --panel: #1c1c1f; --ink: #ececef; --muted: #9a9aa2; --line: #2e2e33;
    --accent: #4fb3bc; --accent-ink: #0d1415; --good: #6cc48a;
    --square: #4f7ea8; --tilted: #c27a3a; --edge: #0d0d0f;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #131315; --panel: #1c1c1f; --ink: #ececef; --muted: #9a9aa2; --line: #2e2e33;
  --accent: #4fb3bc; --accent-ink: #0d1415; --good: #6cc48a;
  --square: #4f7ea8; --tilted: #c27a3a; --edge: #0d0d0f;
  color-scheme: dark;
}

* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
}
header, main, footer { max-width: 960px; margin: 0 auto; padding: 0 16px; }
header { padding-top: 32px; }
h1 { font-size: 1.8rem; margin: 0 0 8px; }
h2 { font-size: 1.1rem; margin: 0 0 12px; }
.lede { color: var(--muted); max-width: 70ch; margin: 0 0 24px; }
.hint { color: var(--muted); font-size: 0.875rem; font-weight: normal; }
a { color: var(--accent); }

main { display: grid; gap: 16px; grid-template-columns: 1fr; }
@media (min-width: 900px) { main { grid-template-columns: 1fr 1fr; } .controls { grid-column: 1 / -1; } }
.panel { background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 16px; min-width: 0; }

label { display: block; font-weight: 600; margin-bottom: 4px; }
input, select {
  font: inherit; color: var(--ink); background: var(--bg); border: 1px solid var(--line);
  border-radius: 6px; padding: 8px 10px;
}
#name, #email { width: 100%; max-width: 480px; }
.email-visibility { display: flex; align-items: center; gap: 8px; margin: 12px 0 4px; }
.email-visibility input { width: 1.1rem; height: 1.1rem; padding: 0; accent-color: var(--accent); }
#email-privacy-hint { margin-top: 4px; }
.row { display: flex; flex-wrap: wrap; gap: 16px; align-items: end; margin-top: 12px; }
.row label { font-weight: 600; }
.row select { display: block; margin-top: 4px; }
.row input[type="number"] { display: block; margin-top: 4px; width: 7rem; }
button.primary {
  font: inherit; font-weight: 600; padding: 9px 22px; border-radius: 6px; border: 0; cursor: pointer;
  background: var(--accent); color: var(--accent-ink);
}
button:focus-visible, input:focus-visible, select:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.cards { display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); }
.card {
  text-align: left; font: inherit; color: inherit; background: var(--bg); border: 1px solid var(--line);
  border-radius: 8px; padding: 10px 12px; cursor: pointer;
}
.card.selected { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.card-head { display: flex; justify-content: space-between; margin-bottom: 6px; }
.card dl { display: grid; grid-template-columns: auto 1fr; gap: 2px 10px; margin: 0 0 6px; font-size: 0.875rem; }
.card dt { color: var(--muted); }
.card dd { margin: 0; font-variant-numeric: tabular-nums; text-align: right; }
.good { color: var(--good); font-weight: 600; }

canvas { width: 100%; max-width: 600px; height: auto; aspect-ratio: 1; display: block; }
.log { list-style: none; margin: 0; padding: 0; font-size: 0.875rem; font-variant-numeric: tabular-nums; }
.log li { padding: 6px 0; border-bottom: 1px solid var(--line); overflow-wrap: anywhere; }
footer { padding: 24px 16px 40px; }