:root {
  --ink: #14282c;
  --muted: #5d6a6e;
  --line: #d9e0df;
  --panel: #fff;
  --bg: #f4f2ed;
  --accent: #005f6b;
  --danger: #b91f31;
  --ok: #176d42;
  --warn: #8a5a00;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.45;
}

header {
  background: #111;
  color: #fff;
  padding: 20px 24px;
}

header h1 {
  margin: 0;
  font-size: 24px;
}

header p {
  margin: 6px 0 0;
  color: #dce4e3;
}

main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 24px;
}

.hidden {
  display: none !important;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 20px;
  margin-bottom: 18px;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  margin-top: 14px;
}

.toolbar.compact {
  display: grid;
}

button {
  min-height: 40px;
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
  padding: 8px 12px;
  font: inherit;
  cursor: pointer;
}

button.secondary {
  background: #fff;
  color: var(--accent);
}

button.danger,
button.secondary.danger {
  border-color: var(--danger);
  background: var(--danger);
  color: #fff;
}

button:disabled {
  opacity: .45;
  cursor: default;
}

.meta,
small {
  color: var(--muted);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(130px, 1fr));
  gap: 10px;
  margin: 16px 0;
}

.stat-card {
  border: 1px solid var(--line);
  background: #fbfcfb;
  padding: 12px;
}

.stat-card span {
  display: block;
  color: var(--muted);
  font-size: 13px;
}

.stat-card strong {
  display: block;
  margin-top: 4px;
  font-size: 24px;
}

.exam-topbar {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: center;
  border-bottom: 1px solid var(--line);
  padding-bottom: 14px;
  margin-bottom: 18px;
}

.timer {
  font-size: 28px;
  font-weight: 700;
  white-space: nowrap;
}

.timer.warning {
  color: var(--danger);
}

.exam-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 20px;
  align-items: start;
}

.question-nav {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 6px;
  max-height: 420px;
  overflow: auto;
}

.nav-dot {
  min-height: 34px;
  padding: 4px;
  border-color: var(--line);
  background: #fff;
  color: var(--ink);
}

.nav-dot.active {
  border-color: var(--accent);
  box-shadow: inset 0 -4px 0 var(--accent);
}

.nav-dot.answered {
  background: #eaf5ef;
  border-color: var(--ok);
}

.nav-dot.flagged {
  color: var(--warn);
  border-color: var(--warn);
}

.question-card h2 {
  font-size: 22px;
  line-height: 1.35;
  margin-top: 0;
}

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

.choice {
  width: 100%;
  text-align: left;
  background: #fff;
  color: var(--ink);
  border-color: var(--line);
  min-height: 48px;
}

.choice.selected {
  border-color: var(--accent);
  box-shadow: inset 4px 0 0 var(--accent);
}

.dashboard-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.stat-list {
  display: grid;
  gap: 8px;
}

.stat-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  border-top: 1px solid var(--line);
  padding-top: 8px;
}

.review-list {
  display: grid;
  gap: 10px;
}

.failed-item {
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.failed-item p {
  margin: 8px 0;
}

.source-excerpt {
  background: #f6faf8;
  border-left: 4px solid var(--accent);
  padding: 10px 12px;
}

@media (max-width: 820px) {
  main {
    padding: 14px;
  }

  .stats-grid,
  .exam-layout,
  .dashboard-columns {
    grid-template-columns: 1fr;
  }

  .exam-topbar {
    align-items: flex-start;
  }
}