:root {
  color-scheme: light;
  --bg: #f7faf7;
  --paper: #ffffff;
  --paper-soft: #f0f6f2;
  --ink: #17211b;
  --muted: #69766f;
  --line: #dbe6df;
  --accent: #28785a;
  --accent-strong: #155f45;
  --amber: #b7791f;
  --wrong: #b43a3a;
  --shadow: 0 18px 46px rgba(22, 45, 34, 0.12);
  --radius: 8px;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    linear-gradient(180deg, rgba(40, 120, 90, 0.08), transparent 260px),
    var(--bg);
  color: var(--ink);
}

button,
input,
select {
  font: inherit;
}

.app-shell {
  width: min(100%, 460px);
  min-height: 100vh;
  margin: 0 auto;
  padding: max(18px, env(safe-area-inset-top)) 16px max(18px, env(safe-area-inset-bottom));
  display: grid;
  grid-template-rows: auto auto auto auto 1fr auto;
  gap: 14px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.school {
  margin: 0 0 4px;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 700;
}

h1 {
  margin: 0;
  font-size: 24px;
  line-height: 1.15;
  letter-spacing: 0;
}

.icon-button,
.pager-btn {
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
  display: inline-grid;
  place-items: center;
  cursor: pointer;
  box-shadow: 0 8px 18px rgba(23, 33, 27, 0.08);
}

.icon-button {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  font-size: 20px;
}

.status-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.status-strip > div {
  min-height: 64px;
  padding: 10px 8px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.82);
  display: grid;
  align-content: center;
  gap: 2px;
}

.status-strip strong {
  font-size: 20px;
  line-height: 1;
}

.status-strip span {
  color: var(--muted);
  font-size: 12px;
}

.module-tabs {
  min-height: 46px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper-soft);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 4px;
}

.tab {
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
}

.tab.is-active {
  background: var(--paper);
  color: var(--accent-strong);
  box-shadow: 0 6px 14px rgba(22, 45, 34, 0.08);
}

.controls {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
}

.select-wrap,
.search-wrap {
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  display: flex;
  align-items: center;
}

.select-wrap {
  padding: 0 10px;
  gap: 8px;
}

.select-wrap span,
.search-wrap span {
  color: var(--muted);
  font-size: 12px;
}

select,
input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--ink);
}

select {
  font-size: 13px;
  font-weight: 700;
}

.search-wrap {
  padding: 0 12px;
  gap: 8px;
}

@media (max-width: 460px) {
  .controls {
    grid-template-columns: 1fr 1fr;
  }

  .search-wrap {
    grid-column: 1 / -1;
  }
}

@media (max-width: 360px) {
  .controls {
    grid-template-columns: 1fr;
  }

  .stem {
    font-size: 18px;
  }
}

.card-stage {
  min-height: 420px;
  display: flex;
  min-width: 0;
}

.question-card {
  width: 100%;
  min-height: 100%;
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.chip {
  padding: 4px 8px;
  border-radius: 999px;
  background: var(--paper-soft);
  color: var(--accent-strong);
  font-size: 12px;
  font-weight: 700;
}

.chip-order {
  background: #eef3ff;
  color: #38538f;
}

.bookmark {
  width: 36px;
  height: 36px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--paper);
  color: var(--muted);
  cursor: pointer;
}

.bookmark.is-active {
  color: var(--amber);
  border-color: rgba(183, 121, 31, 0.5);
  background: #fff7e8;
}

.stem {
  margin: 0;
  font-size: 20px;
  line-height: 1.55;
  font-weight: 800;
  overflow-wrap: anywhere;
}

.question-figure {
  margin: 0;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fbfdfb;
}

.question-figure img {
  display: block;
  width: 100%;
  max-height: 260px;
  object-fit: contain;
}

.question-figure figcaption {
  margin-top: 7px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.45;
  overflow-wrap: anywhere;
}

.options {
  display: grid;
  gap: 10px;
}

.option {
  min-height: 50px;
  padding: 12px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  text-align: left;
  color: var(--ink);
  cursor: pointer;
}

.option.is-correct {
  border-color: rgba(40, 120, 90, 0.55);
  background: #edf8f1;
}

.option.is-wrong {
  border-color: rgba(180, 58, 58, 0.45);
  background: #fff0f0;
}

.answer-panel {
  min-width: 0;
  border-left: 4px solid var(--accent);
  padding: 12px 12px 12px 14px;
  background: #f6fbf7;
  border-radius: 0 var(--radius) var(--radius) 0;
}

.answer-panel[hidden] {
  display: none;
}

.answer-panel h2 {
  margin: 0 0 8px;
  font-size: 15px;
}

.answer-panel p {
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.65;
  overflow-wrap: anywhere;
}

.source {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
  overflow-wrap: anywhere;
}

.audit-box {
  display: grid;
  gap: 4px;
  margin-top: 10px;
  padding: 9px 10px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #ffffff;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
  overflow-wrap: anywhere;
}

.audit-box strong {
  color: var(--accent-strong);
}

.audit-needs-review {
  border-color: rgba(183, 121, 31, 0.45);
  background: #fffaf0;
}

.audit-needs-review strong {
  color: #8a5b12;
}

.audit-unreviewed {
  border-color: rgba(180, 58, 58, 0.4);
  background: #fff5f5;
}

.audit-unreviewed strong {
  color: var(--wrong);
}

.action-row {
  margin-top: auto;
  display: flex;
  gap: 10px;
}

.primary-action,
.secondary-action {
  min-height: 44px;
  border-radius: var(--radius);
  cursor: pointer;
  font-weight: 800;
}

.primary-action {
  flex: 1;
  border: 0;
  background: var(--accent);
  color: white;
}

.secondary-action {
  width: 112px;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
}

.pager {
  min-height: 52px;
  display: grid;
  grid-template-columns: 52px 1fr 52px;
  align-items: center;
  gap: 12px;
}

.pager-btn {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  font-size: 34px;
  line-height: 1;
}

.pager-btn:disabled {
  opacity: 0.38;
  cursor: default;
}

.page-indicator {
  text-align: center;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.empty-state {
  margin: auto;
  text-align: center;
  color: var(--muted);
}

.empty-state h2 {
  color: var(--ink);
  font-size: 18px;
}

@media (max-width: 360px) {
  .app-shell {
    padding-inline: 12px;
  }

  .controls {
    grid-template-columns: 1fr;
  }

  .stem {
    font-size: 18px;
  }
}