:root {
  --bg: #f3f7fb;
  --panel: #ffffff;
  --ink: #12263a;
  --muted: #5d7083;
  --accent: #0067b8;
  --accent-strong: #004d8a;
  --ok-bg: #e7f8ef;
  --ok-ink: #107341;
  --bad-bg: #fdeced;
  --bad-ink: #a5252f;
  --border: #d2deea;
  --reveal-bg: #edf6ff;
  --reveal-border: #9cc5ea;
  --topbar-sticky-offset: 82px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", "Calibri", "Helvetica Neue", sans-serif;
  color: var(--ink);
  min-height: 100vh;
  background: radial-gradient(circle at 10% 20%, #ffffff 0%, #eef5fc 35%, #e5eef7 100%);
}

.app-shell {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(243, 247, 251, 0.96);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
  margin-bottom: 18px;
}

.eyebrow {
  margin: 0;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-size: 0.75rem;
  color: var(--muted);
}

h1 {
  margin: 4px 0 0;
  font-size: clamp(1.2rem, 2vw, 1.8rem);
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 8px 30px rgba(13, 46, 79, 0.08);
}

.hidden {
  display: none;
}

.instruction-list {
  margin: 12px 0 20px;
  padding-left: 18px;
  color: var(--muted);
}

.instruction-list li {
  margin-bottom: 8px;
}

.field-row {
  display: grid;
  gap: 8px;
  max-width: 260px;
  margin-top: 14px;
}

.field-row label {
  font-size: 0.9rem;
  color: var(--muted);
}

.select {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 9px 10px;
  background: #ffffff;
  color: var(--ink);
  font-weight: 600;
}

.exam-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: var(--topbar-sticky-offset);
  z-index: 30;
  background: var(--panel);
  gap: 12px;
  margin-bottom: 16px;
  padding-top: 8px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
  color: var(--muted);
}

.progress-summary {
  margin: 0;
  color: var(--muted);
}

#questionText {
  margin-top: 0;
  margin-bottom: 12px;
  line-height: 1.6;
  white-space: pre-line;
}

.question-media {
  display: grid;
  gap: 10px;
  margin-bottom: 18px;
}

.options {
  display: grid;
  gap: 12px;
  margin-top: 0;
  margin-bottom: 18px;
}

.option {
  display: flex;
  gap: 10px;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  align-items: flex-start;
}

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

.option input {
  margin-top: 3px;
}

.option b {
  margin-right: 8px;
}

.option-content {
  display: grid;
  gap: 8px;
}

.media-group {
  display: grid;
  gap: 8px;
}

.exam-image {
  width: 100%;
  max-width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #ffffff;
}

.media-fallback {
  font-size: 0.85rem;
  color: var(--muted);
}

.answer-reveal {
  margin: 0 0 16px;
  padding: 10px 12px;
  border: 1px solid var(--reveal-border);
  border-radius: 10px;
  background: var(--reveal-bg);
  color: var(--accent-strong);
  font-weight: 600;
}

.answer-list {
  display: grid;
  gap: 8px;
  margin-top: 8px;
}

.answer-item {
  display: grid;
  gap: 8px;
}

.result-answer-row {
  margin-top: 8px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.actions.between {
  justify-content: space-between;
  margin-bottom: 16px;
}

.answer-actions {
  margin-bottom: 16px;
}

.pager {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

.page-numbers {
  display: flex;
  justify-content: center;
  gap: 6px;
  flex-wrap: wrap;
}

.page-btn {
  min-width: 42px;
  padding-left: 10px;
  padding-right: 10px;
}

.page-btn.answered {
  border-color: #8ec5ea;
  background: #eaf5ff;
}

.page-btn.current {
  border-color: var(--accent);
  background: var(--accent);
  color: #ffffff;
}

.btn {
  border: 1px solid var(--border);
  background: #f8fbff;
  color: var(--ink);
  padding: 10px 14px;
  border-radius: 10px;
  cursor: pointer;
  font-weight: 600;
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

.btn.primary:hover {
  background: var(--accent-strong);
}

.btn.ghost {
  background: #ffffff;
}

#scoreSummary {
  margin-top: 0;
  color: var(--muted);
}

.result-list {
  display: grid;
  gap: 10px;
  margin-bottom: 20px;
}

.result-item {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
}

.result-item.ok {
  border-color: #b8e6c9;
  background: var(--ok-bg);
}

.result-item.bad {
  border-color: #f4c8cb;
  background: var(--bad-bg);
}

.result-state {
  font-weight: 700;
  margin-bottom: 6px;
}

.result-item.ok .result-state {
  color: var(--ok-ink);
}

.result-item.bad .result-state {
  color: var(--bad-ink);
}

@media (max-width: 820px) {
  :root {
    --topbar-sticky-offset: 98px;
  }

  .card {
    padding: 18px;
  }

  .exam-header {
    flex-direction: column;
    align-items: stretch;
  }

  .pager {
    gap: 6px;
  }

  .pager .btn,
  .page-btn {
    min-height: 40px;
  }
}