:root {
  color-scheme: light;
  --bg: #f7f8fb;
  --card: #ffffff;
  --text: #1a2340;
  --muted: #5b6478;
  --accent: #f5c400;
  --border: #e4e8f0;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

a {
  color: #1d4ed8;
}

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 20px;
}

.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}

.brand {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 16px;
  font-size: 0.92rem;
}

.nav a {
  text-decoration: none;
}

.content {
  padding: 32px 20px 48px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 28px;
}

h1 {
  margin: 0 0 12px;
  font-size: 1.8rem;
}

h2 {
  margin: 28px 0 10px;
  font-size: 1.1rem;
}

p,
li {
  color: var(--text);
}

.muted {
  color: var(--muted);
}

ul {
  padding-left: 1.2rem;
}

.emphasis {
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  border-radius: 12px;
  padding: 16px;
  margin: 20px 0;
}

.hero {
  text-align: center;
  padding: 48px 0 24px;
}

.hero h1 {
  font-size: 2rem;
}

.hero p {
  color: var(--muted);
  font-size: 1.05rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  margin-top: 24px;
}

.button {
  display: inline-block;
  padding: 12px 18px;
  border-radius: 10px;
  background: var(--accent);
  color: var(--text);
  text-decoration: none;
  font-weight: 700;
}

.button.secondary {
  background: var(--card);
  border: 1px solid var(--border);
}

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--card);
  padding: 24px 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer p {
  margin: 4px 0;
  color: var(--muted);
}

@media (max-width: 640px) {
  .site-header .container {
    flex-direction: column;
    align-items: flex-start;
    padding-top: 16px;
    padding-bottom: 16px;
  }

  .card {
    padding: 20px;
  }
}