* {
  box-sizing: border-box;
}

:root {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #1f2937;
  background: #f5f7fa;
}

body {
  margin: 0;
  min-height: 100vh;
}

.site-header {
  background: #111827;
  color: white;
}

.header-inner {
  max-width: 1000px;
  margin: 0 auto;
  padding: 18px 20px;
  display: flex;
  align-items: center;
  gap: 18px;
}

.logo {
  color: white;
  text-decoration: none;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 1px;
}

.subtitle {
  opacity: 0.75;
  font-size: 14px;
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

.hero {
  background: white;
  border-radius: 18px;
  padding: 42px;
  margin-bottom: 24px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.07);
}

.hero.compact {
  text-align: center;
}

.eyebrow {
  font-size: 12px;
  letter-spacing: 1.5px;
  font-weight: 700;
  color: #6b7280;
}

h1 {
  margin: 10px 0 16px;
  font-size: clamp(28px, 5vw, 42px);
}

h2 {
  margin-top: 0;
}

.lead {
  color: #667085;
  line-height: 1.8;
  margin-bottom: 28px;
}

.primary-button {
  display: inline-block;
  border: 0;
  border-radius: 10px;
  padding: 13px 22px;
  background: #111827;
  color: white;
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}

.primary-button:hover {
  opacity: 0.9;
}

.full {
  width: 100%;
  margin-top: 24px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: white;
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.05);
}

.stat-label {
  color: #667085;
  font-size: 14px;
}

.stat-value {
  display: inline-block;
  margin-top: 8px;
  font-size: 34px;
  font-weight: 800;
}

.stat-unit {
  display: inline-block;
  margin-left: 4px;
  color: #667085;
}

.panel {
  background: white;
  border-radius: 16px;
  padding: 28px;
  margin-bottom: 24px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.05);
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag-list span,
.category {
  border-radius: 999px;
  background: #eef2f7;
  padding: 7px 12px;
  font-size: 13px;
}

.muted {
  color: #667085;
  line-height: 1.7;
  margin-bottom: 0;
}

.quiz-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  color: #667085;
}

.quiz-card {
  background: white;
  border-radius: 18px;
  padding: 38px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.07);
}

.quiz-card h1 {
  font-size: clamp(22px, 4vw, 32px);
  line-height: 1.6;
  margin-bottom: 30px;
}

.choices {
  display: grid;
  gap: 12px;
}

.choice {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 17px;
  border: 1px solid #d9dee7;
  border-radius: 12px;
  cursor: pointer;
  line-height: 1.5;
}

.choice:hover {
  background: #f8fafc;
}

.choice input {
  width: 18px;
  height: 18px;
}

.choice-key {
  font-weight: 800;
  min-width: 24px;
}

.result-card {
  background: white;
  border-radius: 18px;
  padding: 38px;
  box-shadow: 0 8px 30px rgba(15, 23, 42, 0.07);
  border-left: 6px solid #111827;
}

.result-card.correct {
  border-left-color: #16a34a;
}

.result-card.incorrect {
  border-left-color: #dc2626;
}

.result-icon {
  font-size: 52px;
  font-weight: 800;
}

.correct .result-icon {
  color: #16a34a;
}

.incorrect .result-icon {
  color: #dc2626;
}

.answer-line {
  color: #667085;
}

.explanation {
  margin-top: 28px;
  padding: 20px;
  background: #f7f8fa;
  border-radius: 12px;
  line-height: 1.8;
}

.actions {
  margin-top: 20px;
  text-align: right;
}

.score {
  font-size: 64px;
  font-weight: 800;
}

.score span {
  font-size: 30px;
  color: #667085;
}

.score-rate {
  font-size: 20px;
  margin-bottom: 28px;
}

.answer-list {
  display: grid;
  gap: 12px;
}

.answer-item {
  display: flex;
  gap: 14px;
  padding: 16px;
  border-radius: 12px;
  background: #f7f8fa;
  border-left: 4px solid #111827;
}

.answer-item.is-correct {
  border-left-color: #16a34a;
}

.answer-item.is-wrong {
  border-left-color: #dc2626;
}

.answer-number {
  font-weight: 800;
}

.answer-body {
  flex: 1;
}

.answer-body p {
  line-height: 1.6;
}

.answer-status {
  font-weight: 700;
}

.answer-status span {
  margin-left: 8px;
  color: #667085;
  font-weight: 400;
}

.answer-body small {
  color: #667085;
}

.site-footer {
  text-align: center;
  color: #98a2b3;
  padding: 24px;
  font-size: 12px;
}

@media (max-width: 700px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 4px;
  }

  .container {
    padding: 20px 12px 40px;
  }

  .hero,
  .quiz-card,
  .result-card,
  .panel {
    padding: 24px 18px;
  }

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

  .quiz-top {
    align-items: flex-start;
    gap: 10px;
    flex-direction: column;
  }
}