/* Self-check quiz player — zero dependencies, no webfonts, no external assets. */

:root {
  color-scheme: light dark;
  --ink: #16181d;
  --ink-soft: #4c5361;
  --paper: #f7f8fa;
  --card: #ffffff;
  --line: #d9dee6;
  --accent: #3949ab;
  --accent-ink: #ffffff;
  --right: #1b7f4b;
  --right-bg: #e7f6ed;
  --wrong: #b3261e;
  --wrong-bg: #fdecea;
  --radius: 10px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e8eaee;
    --ink-soft: #a8b0bd;
    --paper: #14161a;
    --card: #1c1f25;
    --line: #333944;
    --accent: #8c9eff;
    --accent-ink: #14161a;
    --right: #6ede9e;
    --right-bg: #163224;
    --wrong: #ff9a90;
    --wrong-bg: #341c1a;
  }
}

*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

.wrap { max-width: 46rem; margin: 0 auto; padding: 0 1.25rem; }

.skip-link {
  position: absolute;
  left: -9999px;
}
.skip-link:focus {
  left: 1rem;
  top: 1rem;
  padding: 0.5rem 0.75rem;
  background: var(--card);
  border: 2px solid var(--accent);
  border-radius: var(--radius);
  z-index: 10;
}

.topbar {
  background: var(--card);
  border-bottom: 1px solid var(--line);
  padding: 1.75rem 0 1.5rem;
}
.eyebrow {
  margin: 0;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.topbar h1 { margin: 0.25rem 0 0.5rem; font-size: 1.75rem; }
.lede { margin: 0; color: var(--ink-soft); max-width: 38rem; }

main { padding: 1.75rem 0 2.5rem; }

h2 { font-size: 1.25rem; margin: 0 0 0.75rem; }
h3 { font-size: 0.85rem; letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-soft); margin: 1.5rem 0 0.5rem; }

.notice {
  margin: 0 0 1.25rem;
  padding: 0.75rem 1rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  color: var(--ink-soft);
}

.section-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.5rem; }
@media (min-width: 40rem) {
  .section-list { grid-template-columns: 1fr 1fr; }
}

.section-list a {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.75rem;
  padding: 0.7rem 0.9rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: inherit;
  text-decoration: none;
}
.section-list a:hover, .section-list a:focus-visible { border-color: var(--accent); }
.section-list .id { font-variant-numeric: tabular-nums; color: var(--ink-soft); font-size: 0.85rem; }
.section-list .count { color: var(--ink-soft); font-size: 0.8rem; white-space: nowrap; }
.section-list .title { flex: 1 1 auto; }

.crumbs { margin: 0 0 0.75rem; }
.link-button {
  background: none;
  border: 0;
  padding: 0;
  color: var(--accent);
  font: inherit;
  cursor: pointer;
  text-decoration: underline;
}

.progress { margin: 0 0 0.5rem; color: var(--ink-soft); font-size: 0.9rem; }
.prompt { margin: 0 0 1rem; font-size: 1.05rem; }

.options { list-style: none; margin: 0 0 1rem; padding: 0; display: grid; gap: 0.5rem; }
.options button {
  width: 100%;
  text-align: left;
  padding: 0.7rem 0.9rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: inherit;
  font: inherit;
  cursor: pointer;
}
.options button:hover:not([aria-disabled="true"]) { border-color: var(--accent); }
.options button[aria-disabled="true"] { cursor: default; }
.options button[data-state="correct"],
.options button[data-state="answer"] {
  border-color: var(--right);
  background: var(--right-bg);
}
.options button[data-state="chosen"] {
  border-color: var(--wrong);
  background: var(--wrong-bg);
}
.options .marker { font-size: 0.8rem; color: var(--ink-soft); display: block; }

.feedback {
  margin: 0 0 1rem;
  padding: 0.9rem 1rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.feedback .verdict { margin: 0 0 0.5rem; font-weight: 600; }
.feedback[data-correct="true"] .verdict { color: var(--right); }
.feedback[data-correct="false"] .verdict { color: var(--wrong); }
.feedback p { margin: 0 0 0.5rem; }
.feedback ul { margin: 0.25rem 0 0.5rem; padding-left: 1.1rem; }
.feedback li { margin-bottom: 0.35rem; }
.feedback .refs { font-size: 0.85rem; color: var(--ink-soft); }
.feedback a { color: var(--accent); }

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
  align-items: center;
  justify-content: space-between;
  margin: 0;
}
.toggle { color: var(--ink-soft); font-size: 0.9rem; display: inline-flex; gap: 0.4rem; align-items: center; }

button {
  padding: 0.55rem 1rem;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--card);
  color: inherit;
  font: inherit;
  cursor: pointer;
}
button.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }

.score { font-size: 1.1rem; margin: 0 0 1rem; }

.site-footer {
  border-top: 1px solid var(--line);
  padding-top: 1.25rem;
  padding-bottom: 2.5rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
}
.site-footer a { color: var(--accent); }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }