:root {
  --color-bg: #f7faf8;
  --color-surface: #ffffff;
  --color-text: #1d3229;
  --color-text-secondary: #4b6357;
  --color-text-muted: #7d9488;
  --color-border: #dce8e0;
  --color-accent: #1f8a5d;
  --color-accent-dark: #14683f;
  --color-accent-soft: #e6f4ec;
  --color-warn: #c05621;
  --color-warn-soft: #fdf1e7;
  --radius-md: 14px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 3px rgba(29, 50, 41, 0.06);
  --shadow-md: 0 6px 18px rgba(29, 50, 41, 0.09);
  --transition: 0.25s ease;
  --container-max: 1080px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background-color: rgba(247, 250, 248, 0.88);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-accent-dark);
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--color-accent);
}

/* ---------- Hero ---------- */

.hero {
  padding: 88px 24px 72px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero-tag {
  display: inline-block;
  padding: 6px 18px;
  border-radius: 999px;
  background-color: var(--color-accent-soft);
  color: var(--color-accent-dark);
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.05em;
}

.hero-title {
  margin-top: 22px;
  font-size: 2.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-accent-dark);
}

.hero-sub {
  margin-top: 16px;
  max-width: 620px;
  color: var(--color-text-secondary);
  font-size: 1.02rem;
}

.hero-stats {
  margin-top: 40px;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.stat {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: 20px 30px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 200px;
}

.stat-num {
  font-size: 1.7rem;
  font-weight: 700;
  color: var(--color-accent);
}

.stat-label {
  font-size: 0.88rem;
  color: var(--color-text-muted);
}

.hero-links {
  margin-top: 36px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  display: inline-block;
  padding: 11px 26px;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background-color var(--transition), color var(--transition),
    box-shadow var(--transition), transform var(--transition);
}

.btn:hover {
  transform: translateY(-1px);
}

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

.btn-primary:hover {
  background-color: var(--color-accent-dark);
  box-shadow: var(--shadow-md);
}

.btn-ghost {
  border: 1px solid var(--color-border);
  background-color: var(--color-surface);
  color: var(--color-text-secondary);
}

.btn-ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ---------- Sections ---------- */

.section {
  padding: 72px 24px;
}

.section-alt {
  background-color: #eef5f0;
}

.section-title {
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  text-align: center;
}

.section-subtitle {
  margin-top: 8px;
  color: var(--color-text-muted);
  font-size: 0.98rem;
  text-align: center;
}

/* ---------- Causes cards ---------- */

.card-grid {
  margin-top: 44px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.info-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition),
    border-color var(--transition);
}

.info-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.card-icon {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background-color: var(--color-accent-soft);
  color: var(--color-accent-dark);
  font-size: 1.15rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.info-card h3 {
  font-size: 1.08rem;
  font-weight: 650;
}

.info-card p {
  margin-top: 10px;
  font-size: 0.92rem;
  color: var(--color-text-secondary);
}

.card-scene {
  border-top: 1px dashed var(--color-border);
  padding-top: 12px;
  margin-top: 14px;
  font-size: 0.85rem !important;
  color: var(--color-text-muted) !important;
}

/* ---------- Prevention tips ---------- */

.tip-list {
  margin-top: 44px;
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.tip-item {
  display: flex;
  align-items: flex-start;
  gap: 22px;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition),
    border-color var(--transition);
}

.tip-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.tip-num {
  flex-shrink: 0;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-accent);
  background-color: var(--color-accent-soft);
  border-radius: 50%;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.tip-item h3 {
  font-size: 1.05rem;
  font-weight: 650;
}

.tip-item p {
  margin-top: 6px;
  font-size: 0.93rem;
  color: var(--color-text-secondary);
}

/* ---------- Correction steps ---------- */

.steps {
  margin-top: 44px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.step-card {
  position: relative;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 30px 24px 26px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition),
    border-color var(--transition);
}

.step-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.step-badge {
  position: absolute;
  top: -14px;
  left: 22px;
  padding: 4px 16px;
  border-radius: 999px;
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 600;
}

.step-card h3 {
  margin-top: 6px;
  font-size: 1.08rem;
  font-weight: 650;
}

.step-card p {
  margin-top: 10px;
  font-size: 0.92rem;
  color: var(--color-text-secondary);
}

/* ---------- Correction methods ---------- */

.correction-grid {
  margin-top: 40px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.correction-card {
  border-radius: var(--radius-md);
  padding: 26px 24px;
  background-color: var(--color-accent-soft);
  border: 1px solid #cfe8da;
}

.correction-card h3 {
  font-size: 1.05rem;
  font-weight: 650;
  color: var(--color-accent-dark);
}

.correction-card p {
  margin-top: 10px;
  font-size: 0.92rem;
  color: var(--color-text-secondary);
}

/* ---------- Myths ---------- */

.myths {
  margin-top: 56px;
}

.myths-title {
  font-size: 1.25rem;
  font-weight: 700;
  text-align: center;
}

.myth-grid {
  margin-top: 28px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.myth-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.myth {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-warn);
  background-color: var(--color-warn-soft);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
}

.truth {
  margin-top: 12px;
  font-size: 0.92rem;
  color: var(--color-text-secondary);
}

/* ---------- Notice ---------- */

.notice {
  margin-top: 48px;
  border-left: 4px solid var(--color-accent);
  background-color: var(--color-surface);
  border-radius: var(--radius-sm);
  padding: 18px 22px;
  font-size: 0.92rem;
  color: var(--color-text-secondary);
  box-shadow: var(--shadow-sm);
}

.notice strong {
  color: var(--color-accent-dark);
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 28px 24px;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

/* ---------- Reveal animation ---------- */

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .steps,
  .correction-grid {
    grid-template-columns: 1fr;
  }

  .step-card {
    margin-top: 14px;
  }
}

@media (max-width: 768px) {
  .hero {
    padding: 56px 24px 52px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .card-grid,
  .myth-grid {
    grid-template-columns: 1fr;
  }

  .stat {
    min-width: 150px;
    padding: 16px 20px;
  }

  .section {
    padding: 52px 24px;
  }

  .tip-item {
    flex-direction: column;
    gap: 12px;
  }
}