:root {
  --bg: #fbfaf7;
  --fg: #1c1c1c;
  --muted: #5c5c5c;
  --accent: #2d4a7a;
  --accent-light: #e6ecf5;
  --correct: #1f7a3e;
  --correct-bg: #e3f3e8;
  --wrong: #a32f2f;
  --wrong-bg: #f6e3e3;
  --border: #d6d2c8;
  --card: #ffffff;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 70ch;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 4rem;
}

header h1 {
  font-size: 2rem;
  line-height: 1.2;
  margin: 0 0 0.5rem;
}

.subtitle {
  color: var(--muted);
  margin: 0 0 2rem;
  font-size: 1.05rem;
}

.lede {
  font-size: 1.18rem;
  line-height: 1.55;
  color: #2a2a2a;
  margin-top: 0;
}

.term {
  font-weight: 400;
  font-size: 0.85em;
  color: var(--muted);
  letter-spacing: 0.01em;
}

.pull {
  margin: 1.5rem 0;
  padding: 0.9rem 1.1rem;
  border-left: 3px solid var(--accent);
  background: var(--accent-light);
  font-size: 1.05rem;
  line-height: 1.5;
  border-radius: 0 6px 6px 0;
}

#start-quiz h2 {
  font-size: 1.4rem;
  margin: 0 0 0.6rem;
  color: var(--accent);
}

.share-prompt {
  margin: 1.25rem 0 0.5rem;
  font-size: 0.95rem;
  color: var(--muted);
}

.share-inline {
  margin-top: 1rem;
  font-size: 0.92rem;
  color: var(--muted);
}

.support-prompt {
  margin: 1.5rem 0 0.5rem;
  font-size: 0.95rem;
  color: var(--muted);
}

.support-options {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0 0 0.5rem;
}

.support-btn {
  display: inline-block;
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
  padding: 0.5rem 0.9rem;
  border-radius: 6px;
  font-size: 0.95rem;
  text-decoration: none;
  white-space: nowrap;
  font-weight: 500;
}

.support-btn:hover {
  background: var(--accent-light);
  text-decoration: none;
}

.support-btn-custom {
  border-style: dashed;
  color: var(--muted);
  border-color: var(--muted);
}

.share-btn {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
  padding: 0.5rem 0.9rem;
  font-size: 0.9rem;
  margin-right: 0.5rem;
}

.share-btn:hover {
  background: var(--accent-light);
  filter: none;
}

.share-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

section {
  margin: 2.25rem 0;
}

section h2 {
  font-size: 1.25rem;
  margin: 0 0 0.6rem;
  color: var(--accent);
}

p {
  margin: 0.8rem 0;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

a:hover {
  text-decoration-thickness: 2px;
}

button {
  font: inherit;
  background: var(--accent);
  color: white;
  border: none;
  padding: 0.75rem 1.25rem;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 500;
}

button:hover {
  filter: brightness(1.1);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

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

.restart-btn {
  margin-top: 1.5rem;
}

.load-error {
  color: var(--wrong);
}

#start-quiz {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 2px solid var(--border);
}

/* Quiz styles */
.question-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
}

.question-card .progress {
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.question-card .scenario {
  font-size: 1rem;
  margin: 0.5rem 0 1.25rem;
  padding: 1rem;
  background: var(--bg);
  border-left: 3px solid var(--accent);
  font-style: italic;
}

.options {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin: 0 0 1rem;
}

.option {
  display: block;
  padding: 0.85rem 1rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card);
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
  font: inherit;
  text-align: left;
  width: 100%;
  color: inherit;
}

.option:hover:not(:disabled) {
  background: var(--accent-light);
  border-color: var(--accent);
}

.option:disabled {
  cursor: default;
}

.option.correct {
  background: var(--correct-bg);
  border-color: var(--correct);
  color: var(--correct);
}

.option.wrong {
  background: var(--wrong-bg);
  border-color: var(--wrong);
  color: var(--wrong);
}

.option.faded {
  opacity: 0.55;
}

.feedback {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: 6px;
  background: var(--accent-light);
}

.feedback .verdict {
  font-weight: 600;
  margin: 0 0 0.4rem;
}

.feedback .verdict.correct { color: var(--correct); }
.feedback .verdict.wrong { color: var(--wrong); }

.feedback .explanation {
  margin: 0.4rem 0;
}

.feedback .source {
  font-size: 0.9rem;
  margin-top: 0.6rem;
  color: var(--muted);
}

.controls {
  display: flex;
  justify-content: flex-end;
  margin-top: 1rem;
}

/* Results */
.results-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.5rem;
}

.results-card h2 {
  margin-top: 0;
}

.score-headline {
  font-size: 1.5rem;
  margin: 0.5rem 0 1.25rem;
}

.breakdown {
  margin: 1rem 0;
  border-top: 1px solid var(--border);
}

.breakdown-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border);
  gap: 1rem;
}

.breakdown-row .concept {
  font-weight: 500;
}

.breakdown-row .ratio {
  font-variant-numeric: tabular-nums;
  color: var(--muted);
}

.breakdown-row.weak .ratio { color: var(--wrong); }
.breakdown-row.strong .ratio { color: var(--correct); }

.takeaway {
  margin-top: 1.25rem;
  padding: 1rem;
  background: var(--accent-light);
  border-radius: 6px;
}

footer {
  margin-top: 4rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}

@media (max-width: 480px) {
  main { padding: 1.5rem 1rem 3rem; }
  header h1 { font-size: 1.6rem; }
  .question-card { padding: 1.1rem; }
  .option { padding: 0.75rem 0.85rem; }
}