:root {
  --bg: #f4f6f8; --ink: #101828; --muted: #5b6676; --line: #d5dae1;
  --accent: #0e7c86; --good: #1b8a5a; --bad: #c2412d;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #0f1419; --ink: #eef1f5; --muted: #98a2b3; --line: #2a323d; --accent: #4fc3cc; --good: #4cc38a; --bad: #ff7b66; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: system-ui, sans-serif; line-height: 1.5; }
main { max-width: 32rem; margin: 0 auto; padding: 2rem 1.25rem; }
.trick { color: var(--muted); margin: 0; }
.question { font-size: clamp(2.5rem, 12vw, 4rem); font-weight: 700; font-variant-numeric: tabular-nums; margin: .25rem 0 1rem; }
form { display: flex; gap: .5rem; }
input { flex: 1; min-width: 0; font-size: 1.75rem; padding: .5rem .75rem; border: 2px solid var(--line); border-radius: 8px; background: transparent; color: inherit; font-variant-numeric: tabular-nums; }
input:focus-visible, button:focus-visible, summary:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
button { font-size: 1.1rem; padding: .5rem 1.25rem; border: 0; border-radius: 8px; background: var(--accent); color: var(--bg); font-weight: 600; cursor: pointer; }
.feedback { min-height: 1.5rem; font-weight: 600; }
.feedback.good { color: var(--good); }
.feedback.bad { color: var(--bad); }
#review { border-top: 1px solid var(--line); padding-top: 1rem; }
#steps { padding-left: 1.25rem; font-variant-numeric: tabular-nums; }
details { margin-top: 1.5rem; border-top: 1px solid var(--line); padding-top: 1rem; }
summary { cursor: pointer; font-weight: 600; }
.stats { color: var(--muted); margin-top: 2rem; }