* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  color: #e2e8f0;
  background: #0b111a;
}

a {
  color: inherit;
}

.shell {
  min-height: 100vh;
  padding: 40px 24px 80px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
}

.hero {
  width: min(960px, 100%);
  text-align: center;
  display: grid;
  gap: 10px;
}

.hero__eyebrow {
  margin: 0;
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: rgba(148, 163, 184, 0.7);
}

.hero h1 {
  margin: 0;
  font-size: 32px;
  color: #f8fafc;
}

.hero__subhead {
  margin: 0;
  font-size: 14px;
  color: rgba(226, 232, 240, 0.7);
}

.banner {
  margin: 10px auto 0;
  padding: 12px 18px;
  border-radius: 14px;
  background: rgba(20, 83, 45, 0.28);
  border: 1px solid rgba(34, 197, 94, 0.5);
  color: #bbf7d0;
  font-size: 13px;
}

.assessment {
  width: min(960px, 100%);
  display: grid;
  gap: 20px;
}

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
}

.stat {
  padding: 14px 16px;
  border-radius: 14px;
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(148, 163, 184, 0.2);
}

.stat__label {
  margin: 0 0 8px;
  font-size: 11px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: rgba(148, 163, 184, 0.7);
}

.stat__value {
  margin: 0;
  font-size: 18px;
  font-weight: 600;
}

.card {
  background: rgba(15, 23, 42, 0.65);
  border-radius: 20px;
  padding: 24px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  box-shadow:
    0 24px 48px rgba(2, 6, 23, 0.4),
    inset 0 0 0 1px rgba(148, 163, 184, 0.05);
}

.card--setup {
  display: grid;
  gap: 18px;
}

.card--guide {
  display: grid;
  gap: 14px;
}

.setup__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.panel {
  padding: 18px;
  border-radius: 16px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(15, 23, 42, 0.6);
  display: grid;
  gap: 14px;
}

.panel__header h2 {
  margin: 0 0 6px;
  font-size: 18px;
}

.panel__header p {
  margin: 0;
  font-size: 13px;
}

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

.option {
  display: grid;
  grid-template-columns: 18px 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(2, 6, 23, 0.35);
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.option input {
  margin: 0;
}

.option:hover {
  border-color: rgba(148, 163, 184, 0.5);
}

.option.is-selected {
  border-color: rgba(59, 130, 246, 0.6);
  background: rgba(30, 64, 175, 0.2);
}

.option__label {
  font-weight: 600;
}

.option__meta {
  font-size: 12px;
  color: rgba(148, 163, 184, 0.8);
}

.mode-cards {
  display: grid;
  gap: 12px;
}

.mode-card {
  padding: 14px;
  border-radius: 14px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(2, 6, 23, 0.35);
  display: grid;
  gap: 6px;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.mode-card input {
  display: none;
}

.mode-card__title {
  font-size: 15px;
  font-weight: 600;
}

.mode-card__desc {
  font-size: 12px;
  color: rgba(148, 163, 184, 0.8);
}

.mode-card.is-selected {
  border-color: rgba(59, 130, 246, 0.6);
  background: rgba(30, 64, 175, 0.2);
}

.checkbox {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: rgba(226, 232, 240, 0.8);
}

.checkbox input {
  accent-color: #38bdf8;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 10px;
}

.guide-item {
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(2, 6, 23, 0.3);
  font-size: 13px;
}

.guide-link {
  font-size: 13px;
  text-decoration: none;
  color: #93c5fd;
}

.guide-link:hover {
  text-decoration: underline;
}

.choices {
  display: grid;
  gap: 12px;
  margin: 20px 0;
}

.choice {
  display: grid;
  grid-template-columns: 20px 1fr;
  gap: 12px;
  align-items: start;
  padding: 12px 14px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  border-radius: 12px;
  background: rgba(2, 6, 23, 0.35);
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.choice:hover {
  border-color: rgba(148, 163, 184, 0.5);
}

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

.choice.is-selected {
  border-color: rgba(59, 130, 246, 0.6);
  background: rgba(37, 99, 235, 0.2);
}

.choice.is-correct {
  border-color: rgba(16, 185, 129, 0.7);
  background: rgba(16, 185, 129, 0.2);
}

.choice.is-wrong {
  border-color: rgba(248, 113, 113, 0.7);
  background: rgba(248, 113, 113, 0.2);
}

.feedback {
  min-height: 42px;
  margin-bottom: 12px;
}

.feedback .correct {
  color: #34d399;
  font-weight: 600;
}

.feedback .wrong {
  color: #f87171;
  font-weight: 600;
}

.exam__meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 14px;
  color: rgba(226, 232, 240, 0.75);
  gap: 16px;
}

.exam-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 24px;
}

.exam-main {
  margin-bottom: 0;
}

.exam-sidebar .card {
  margin-bottom: 16px;
}

.progress {
  flex: 1;
}

.progress__text {
  font-weight: 600;
  margin-bottom: 8px;
}

.progress__track {
  width: 100%;
  height: 6px;
  background: rgba(148, 163, 184, 0.2);
  border-radius: 999px;
  overflow: hidden;
}

.progress__bar {
  height: 100%;
  width: 0%;
  background: #60a5fa;
  transition: width 0.3s ease;
}

.question-count {
  margin: 12px 0 8px;
  color: rgba(226, 232, 240, 0.75);
  font-weight: 600;
}

.timer-card h3,
.nav-card h3 {
  margin-top: 0;
}

.timer-grid {
  display: grid;
  gap: 16px;
}

.timer-label {
  margin: 0;
  color: rgba(226, 232, 240, 0.7);
  font-size: 13px;
}

.timer-value {
  margin: 6px 0 0;
  font-size: 22px;
  font-weight: 700;
  color: #e2e8f0;
}

.timer-hint {
  margin: 12px 0 0;
  font-size: 12px;
  color: rgba(226, 232, 240, 0.7);
}

.question-nav {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
  margin-top: 12px;
}

.nav-item {
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(2, 6, 23, 0.35);
  border-radius: 8px;
  height: 36px;
  font-size: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: inherit;
}

.nav-item.is-current {
  border-color: rgba(59, 130, 246, 0.7);
  background: rgba(59, 130, 246, 0.2);
  font-weight: 700;
}

.nav-item.is-answered {
  border-color: rgba(148, 163, 184, 0.6);
  background: rgba(148, 163, 184, 0.2);
}

.legend {
  display: grid;
  gap: 6px;
  margin-top: 12px;
  font-size: 12px;
  color: rgba(226, 232, 240, 0.7);
}

.legend__item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.legend__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

.legend__dot--current {
  background: #60a5fa;
}

.legend__dot--answered {
  background: rgba(148, 163, 184, 0.8);
}

.legend__dot--empty {
  background: rgba(148, 163, 184, 0.3);
}

.actions {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

.btn {
  border-radius: 12px;
  border: 1px solid transparent;
  padding: 10px 18px;
  font-weight: 600;
  cursor: pointer;
}

.btn--primary {
  background: #60a5fa;
  color: #0b1220;
}

.btn--ghost {
  background: rgba(148, 163, 184, 0.15);
  color: #e2e8f0;
  border: 1px solid rgba(148, 163, 184, 0.25);
}

.muted {
  color: rgba(226, 232, 240, 0.7);
}

.is-hidden {
  display: none;
}

.review {
  display: grid;
  gap: 16px;
  margin: 16px 0 24px;
}

.review__item {
  border: 1px solid rgba(148, 163, 184, 0.2);
  border-radius: 12px;
  padding: 16px;
  background: rgba(2, 6, 23, 0.35);
}

.review__item h3 {
  margin: 0 0 8px;
}

.review__item p {
  margin: 6px 0;
}

@media (max-width: 720px) {
  .hero h1 {
    font-size: 26px;
  }

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

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

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