:root {
  --bg: #ffffff;
  --bg-soft: #f6f6f4;
  --text: #1a1a1a;
  --muted: #555555;
  --line: #e6e3df;
  --accent: #0b646f;
  --accent-soft: #e5f0f0;
  --code-bg: #f2f2f0;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: linear-gradient(180deg, #ffffff 0%, #f7f7f6 100%);
  color: var(--text);
  font-family: "Noto Serif SC", "Source Han Serif SC", "Noto Serif", serif;
  line-height: 1.7;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 20px;
}

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

.site-header .container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 20px;
}

.brand-title {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: var(--text);
}

.brand-subtitle {
  margin: 6px 0 0;
  font-size: 14px;
  color: var(--muted);
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  font-size: 15px;
}

.nav a {
  color: var(--text);
  padding: 6px 10px;
  border-radius: 999px;
  background: transparent;
}

.nav a:hover {
  background: var(--bg-soft);
  text-decoration: none;
}

.page {
  padding: 28px 0 56px;
  animation: fadeIn 240ms ease-out;
}

.hero {
  padding: 32px 0 24px;
}

.hero-title {
  font-size: 36px;
  margin: 0 0 8px;
}

.hero-subtitle {
  margin: 0 0 18px;
  color: var(--muted);
  font-size: 17px;
}

.notice {
  display: inline-block;
  padding: 6px 12px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 12px;
  border-radius: 999px;
}

.section-title {
  font-size: 20px;
  margin: 28px 0 12px;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
  background: var(--bg);
}

.card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.post-list {
  display: grid;
  gap: 18px;
}

.post-card {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg);
}

.post-card h2 {
  margin: 0 0 8px;
  font-size: 22px;
}

.post-meta {
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 10px;
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.badge {
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--muted);
}

.post-detail h1 {
  margin-top: 0;
  font-size: 30px;
}

.post-detail p {
  margin: 12px 0;
}

.post-detail h2 {
  margin: 26px 0 10px;
  font-size: 22px;
}

pre {
  background: var(--code-bg);
  padding: 14px;
  border-radius: 10px;
  overflow-x: auto;
}

code {
  font-family: "Fira Code", "JetBrains Mono", "SFMono-Regular", monospace;
  font-size: 13px;
}

.form-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
  background: var(--bg);
  max-width: 420px;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 14px;
}

.form-field input {
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--line);
  font-size: 14px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 16px;
  background: var(--accent);
  color: #ffffff;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  font-size: 14px;
}

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

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

.site-footer {
  border-top: 1px solid var(--line);
  padding: 20px 0 30px;
  background: var(--bg);
  color: var(--muted);
}

.footer-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  justify-content: space-between;
}

.footer-title {
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.footer-note {
  margin: 0;
  font-size: 13px;
}

.footer-meta {
  font-size: 12px;
  margin-top: 6px;
}

.small-text {
  font-size: 13px;
  color: var(--muted);
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page {
    animation: none;
  }
}

@media (max-width: 1000px) {
  .container {
    padding: 0 22px;
  }

  .site-header .container {
    flex-direction: column;
    align-items: flex-start;
  }

  .page {
    padding: 22px 22px 44px 22px;
  }

  .hero {
    padding: 24px 0 18px;
  }

  .hero-title {
    font-size: 30px;
  }

  .nav {
    width: 100%;
  }

  .card,
  .post-card,
  .form-card {
    padding: 18px;
  }

  .site-footer {
    padding: 24px 0 32px;
  }
}