:root {
  color-scheme: light;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #20252c;
  background: #f7f8fa;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}
* { box-sizing: border-box; }
body { margin: 0; }
button, input { font: inherit; }
button, a, input, summary { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-underline-offset: 4px; }
button { cursor: pointer; }
button:focus-visible, a:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 2px solid #2655a6;
  outline-offset: 4px;
}
[hidden] { display: none !important; }
.site-header {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 0 max(24px, calc((100% - 1120px) / 2));
  background: #fff;
  border-bottom: 1px solid #e0e4e9;
}
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: 20px; font-weight: 700; letter-spacing: -0.04em; text-decoration: none; }
.brand svg { width: 22px; height: 22px; color: #2655a6; }
.brand-party { color: #2655a6; }
.site-header nav { display: flex; align-self: stretch; gap: 28px; }
.site-header nav a { display: flex; align-items: center; padding: 2px 0 0; border-bottom: 2px solid transparent; font-size: 14px; color: #68717e; text-decoration: none; }
.site-header nav a[aria-current] { color: #20252c; border-color: #20252c; }
.practice-shell { width: min(1120px, calc(100% - 48px)); margin: 0 auto; }
.page-heading { display: flex; justify-content: space-between; align-items: center; gap: 24px; padding: 38px 0 32px; }
h1 { margin: 0; font-size: 30px; font-weight: 650; letter-spacing: -0.04em; }
.page-heading p { margin: 10px 0 0; color: #68717e; font-size: 14px; line-height: 1.5; }
.progress-counts { display: flex; gap: 32px; margin: 0; }
.progress-counts div { display: flex; flex-direction: column-reverse; gap: 4px; }
.progress-counts dt { color: #68717e; font-size: 12px; }
.progress-counts dd { margin: 0; font-size: 24px; font-weight: 600; font-variant-numeric: tabular-nums; }
.practice-layout { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 64px; padding: 28px 0 48px; border-top: 1px solid #e0e4e9; }
fieldset { min-width: 0; margin: 0; padding: 0; border: 0; }
legend { padding: 0; font-size: 14px; font-weight: 600; }
.topic-filters summary { cursor: pointer; font-size: 14px; font-weight: 600; }
.topic-filters summary span { margin-left: 8px; color: #68717e; font-size: 12px; font-weight: 400; }
.topic-shortcuts { display: flex; gap: 8px; align-items: center; margin: 4px 0 8px; color: #c0c6ce; }
.topic-shortcuts button { min-height: 36px; padding: 0 4px; border: 0; background: none; color: #68717e; font-size: 12px; }
.topic-shortcuts button:first-child { padding-left: 0; }
.topic-shortcuts button:hover { color: #20252c; text-decoration: underline; }
.topic-option, .review-toggle { display: flex; align-items: center; gap: 10px; min-height: 40px; cursor: pointer; font-size: 14px; line-height: 1.5; }
input[type="checkbox"] { flex-shrink: 0; width: 16px; height: 16px; margin: 0; accent-color: #365b93; cursor: pointer; }
.review-toggle { margin-top: 22px; padding-top: 18px; border-top: 1px solid #e0e4e9; }
.save-note { margin: 24px 0 0; color: #68717e; font-size: 12px; line-height: 1.6; }
.save-note.is-warning { color: #8b4c18; }
.question-area { min-width: 0; padding-top: 2px; }
.question-meta { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin: 0 0 22px; color: #68717e; font-size: 12px; }
.question-points { flex-shrink: 0; color: #20252c; font-size: 16px; font-weight: 600; font-variant-numeric: tabular-nums; }
.question-area h2 { max-width: 28ch; margin: 0; font-size: clamp(26px, 2.8vw, 36px); font-weight: 550; letter-spacing: -0.035em; line-height: 1.35; overflow-wrap: anywhere; }
.question-area h2:focus { outline: none; }
.question-hint { margin-top: 26px; color: #68717e; font-size: 14px; }
.question-hint summary { display: list-item; width: fit-content; padding: 10px 0; cursor: pointer; }
.question-hint p { max-width: 58ch; margin: 4px 0 0; color: #4b5563; line-height: 1.65; }
.question-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 28px; }
.button { min-height: 44px; padding: 10px 18px; border: 1px solid #cbd1d9; border-radius: 5px; color: #20252c; background: #fff; font-size: 14px; font-weight: 550; }
.button:hover { background: #edf0f4; }
.button-primary { background: #252b35; border-color: #252b35; color: #fff; }
.button-primary:hover { background: #414b5b; }
.text-button { min-height: 44px; padding: 10px 12px; border: 0; background: transparent; color: #68717e; font-size: 14px; }
.text-button:hover { color: #20252c; text-decoration: underline; }
.answer-section { margin-top: 30px; padding-top: 24px; border-top: 1px solid #e0e4e9; }
.answer-label { margin: 0 0 10px; color: #68717e; font-size: 12px; }
.answer-section h3 { margin: 0; font-size: 24px; font-weight: 600; letter-spacing: -0.02em; line-height: 1.4; }
.answer-explanation { max-width: 62ch; margin: 14px 0 0; color: #4b5563; line-height: 1.75; font-size: 15px; }
.answer-source { display: inline-block; margin-top: 12px; color: #365b93; font-size: 12px; }
.answer-rating { margin: 26px 0 0; color: #68717e; font-size: 12px; }
.answer-section .question-actions { margin-top: 10px; }
.empty-state { padding: 36px 0; }
.empty-state p { max-width: 48ch; color: #68717e; font-size: 15px; line-height: 1.7; }
.empty-state button { margin-top: 12px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
@media (max-width: 760px) {
  .site-header { min-height: 62px; padding-inline: 20px; gap: 16px; }
  .brand { font-size: 18px; gap: 8px; }
  .brand svg { width: 18px; height: 18px; }
  .site-header nav { gap: 18px; }
  .site-header nav a { font-size: 13px; }
  .practice-shell { width: calc(100% - 40px); }
  .page-heading { padding: 26px 0 24px; align-items: start; }
  h1 { font-size: 27px; }
  .page-heading p { max-width: 22ch; font-size: 13px; }
  .progress-counts { gap: 18px; padding-top: 3px; flex-shrink: 0; }
  .progress-counts dd { font-size: 22px; }
  .progress-counts dt { font-size: 11px; }
  .practice-layout { grid-template-columns: 1fr; gap: 28px; padding-top: 20px; }
  .practice-options { display: grid; grid-template-columns: 1fr; }
  #topic-options { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 12px; }
  .topic-option { min-height: 38px; font-size: 13px; }
  .topic-filters summary { padding: 8px 0; }
  .review-toggle { margin-top: 14px; padding-top: 14px; }
  .save-note { margin-top: 12px; }
  .question-area { border-top: 1px solid #e0e4e9; padding-top: 26px; }
  .question-area h2 { font-size: 27px; }
  .question-meta { margin-bottom: 16px; }
}
@media (prefers-reduced-motion: no-preference) {
  .button { transition: background-color 120ms ease; }
}