:root {
  /* Light mode colors */
  --bg: #FDFCF8;
  --on-bg: #1A1A1A;
  --surface: #FFFFFF;
  --on-surface: #1A1A1A;
  --on-surface-variant: #6B6B6B;
  --primary: #1A1A1A;
  --on-primary: #FDFCF8;
  --primary-container: #EAE8E1;
  --on-primary-container: #1A1A1A;
  --secondary: #8B4513;
  --on-secondary: #FFFFFF;
  --secondary-container: #F5E6D3;
  --on-secondary-container: #5A2D0C;
  --outline: #D4D0C8;
  --outline-variant: #EAE8E1;
  --muted: #9B9B9B;
  --accent: #8B4513;
  --accent-hover: #6B3410;
  --success: #2D6A4F;
  --warning: #B35900;
  --error: #C0392B;
  --info: #2874A6;
}

[data-theme="dark"] {
  --bg: #121212;
  --on-bg: #E8E6E1;
  --surface: #1E1E1E;
  --on-surface: #E8E6E1;
  --on-surface-variant: #A8A5A0;
  --primary: #E8E6E1;
  --on-primary: #121212;
  --primary-container: #2A2A2A;
  --on-primary-container: #E8E6E1;
  --secondary: #C9A87C;
  --on-secondary: #121212;
  --secondary-container: #3D2A1A;
  --on-secondary-container: #F5E6D3;
  --outline: #3D3D3D;
  --outline-variant: #2A2A2A;
  --muted: #7A7875;
  --accent: #C9A87C;
  --accent-hover: #D4B896;
  --success: #4CAF50;
  --warning: #FF9800;
  --error: #F44336;
  --info: #2196F3;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: Inter, -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 1rem;
  line-height: 1.7;
  color: var(--on-bg);
  background-color: var(--bg);
  transition: background-color 200ms ease, color 200ms ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Typography */
h1, h2, h3, .display {
  font-family: Georgia, 'Times New Roman', serif;
  font-weight: 400;
}

.display {
  font-size: 3.5rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 2.5rem;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

h2 {
  font-size: 1.875rem;
  line-height: 1.3;
}

h3 {
  font-size: 1.5rem;
  line-height: 1.4;
}

.body-lg {
  font-size: 1.125rem;
  line-height: 1.75;
}

.body-sm {
  font-size: 0.875rem;
  line-height: 1.6;
}

.label {
  font-size: 0.75rem;
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.mono {
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 0.875rem;
  line-height: 1.6;
}

/* Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.reading-column {
  max-width: 680px;
  margin: 0 auto;
}

section {
  padding: 80px 0;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--outline-variant);
  background-color: var(--bg);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color 200ms ease;
}

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

.site-title {
  font-family: Georgia, 'Times New Roman', serif;
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--primary);
  text-decoration: none;
}

.site-title:hover {
  color: var(--accent);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.site-nav a {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--on-surface-variant);
  text-decoration: none;
  transition: color 150ms ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--primary);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 8px;
  color: var(--on-surface-variant);
  transition: background-color 150ms ease, color 150ms ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background-color: var(--primary-container);
  color: var(--primary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--on-surface-variant);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--outline-variant);
  padding: 48px 0;
  margin-top: auto;
}

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

.footer-left {
  color: var(--muted);
  font-size: 0.875rem;
}

.footer-right {
  display: flex;
  gap: 24px;
}

.footer-right a {
  color: var(--on-surface-variant);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color 150ms ease;
}

.footer-right a:hover {
  color: var(--accent);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: background-color 150ms ease, color 150ms ease;
}

.btn-primary {
  background-color: var(--primary);
  color: var(--on-primary);
}

.btn-primary:hover {
  background-color: var(--accent);
  color: var(--on-primary);
}

.btn-ghost {
  background-color: transparent;
  color: var(--primary);
}

.btn-ghost:hover {
  background-color: var(--primary-container);
}

/* Cards */
.card {
  background-color: var(--surface);
  border-radius: 12px;
  padding: 24px;
  border: 1px solid var(--outline-variant);
  transition: border-color 150ms ease, background-color 200ms ease;
}

.card:hover {
  border-color: var(--outline);
}

/* App Cards */
.app-card {
  background-color: var(--surface);
  border-radius: 8px;
  padding: 16px;
  border: 1px solid var(--outline-variant);
  transition: border-color 150ms ease, background-color 150ms ease;
}

.app-card:hover {
  border-color: var(--outline);
  background-color: var(--primary-container);
}

.app-card h3 {
  font-size: 1.25rem;
  margin-bottom: 8px;
}

.app-card p {
  color: var(--on-surface-variant);
  font-size: 0.875rem;
  margin-bottom: 12px;
}

.app-card .app-link {
  color: var(--accent);
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 0.75rem;
  text-decoration: none;
}

.app-card .app-link:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

/* Article Cards */
.article-card {
  display: block;
  text-decoration: none;
  color: inherit;
  padding: 24px 0;
  border-bottom: 1px solid var(--outline-variant);
}

.article-card:first-child {
  padding-top: 0;
}

.article-card:hover h3 {
  color: var(--accent);
}

.article-card .tag {
  display: inline-block;
  margin-bottom: 12px;
}

.article-card h3 {
  margin-bottom: 8px;
  transition: color 150ms ease;
}

.article-card .excerpt {
  color: var(--on-surface-variant);
  font-size: 0.875rem;
  line-height: 1.6;
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card .meta {
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

/* Tags */
.tag {
  background-color: var(--primary-container);
  color: var(--on-primary-container);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 4px 12px;
  border-radius: 4px;
  text-decoration: none;
  transition: background-color 150ms ease, color 150ms ease;
  display: inline-block;
}

.tag:hover {
  background-color: var(--accent);
  color: #FFFFFF;
}

/* Status Badges */
.status-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: #FFFFFF;
}

.status-live { background-color: var(--success); }
.status-beta { background-color: var(--warning); }
.status-archived { background-color: var(--muted); }
.status-experimental { background-color: var(--info); }

/* Grids */
.grid {
  display: grid;
  gap: 16px;
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

/* Hero */
.hero {
  padding: 120px 0 80px;
}

.hero .display {
  max-width: 800px;
  margin-bottom: 24px;
}

.hero .body-lg {
  max-width: 600px;
  color: var(--on-surface-variant);
  margin-bottom: 32px;
}

/* Section Header */
.section-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 32px;
}

.section-header h2 {
  margin: 0;
}

.section-header a {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--accent);
  text-decoration: none;
}

.section-header a:hover {
  color: var(--accent-hover);
}

/* Filters */
.filter-bar {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.filter-btn {
  background: none;
  border: 1px solid var(--outline);
  color: var(--on-surface-variant);
  padding: 8px 16px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 150ms ease;
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--primary);
  color: var(--on-primary);
  border-color: var(--primary);
}

/* Article Page */
.article-header {
  padding: 80px 0 48px;
}

.article-header h1 {
  margin-bottom: 16px;
}

.article-meta {
  display: flex;
  gap: 16px;
  align-items: center;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.article-body {
  padding-bottom: 80px;
}

.article-body p {
  margin-bottom: 24px;
}

.article-body p:first-child {
  font-size: 1.125rem;
  line-height: 1.75;
}

.article-body h2 {
  margin-top: 48px;
  margin-bottom: 16px;
}

.article-body h3 {
  margin-top: 32px;
  margin-bottom: 12px;
}

.article-body blockquote {
  border-left: 4px solid var(--accent);
  padding: 16px 24px;
  margin: 32px 0;
  background-color: var(--primary-container);
  font-family: Georgia, 'Times New Roman', serif;
  font-style: italic;
  border-radius: 0 8px 8px 0;
}

.article-body code {
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 0.875rem;
  background-color: var(--surface);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--outline-variant);
}

.article-body pre {
  background-color: var(--surface);
  padding: 16px;
  border-radius: 8px;
  border: 1px solid var(--outline-variant);
  overflow-x: auto;
  margin: 24px 0;
}

.article-body pre code {
  background: none;
  border: none;
  padding: 0;
}

.article-body img {
  width: 100%;
  border-radius: 12px;
  margin: 32px 0;
}

/* Contact Form */
.contact-form {
  max-width: 600px;
}

.form-group {
  margin-bottom: 24px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--on-surface-variant);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border-radius: 8px;
  border: 1px solid var(--outline);
  background-color: var(--surface);
  color: var(--on-surface);
  font-family: Inter, -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
  transition: border-color 150ms ease, outline 150ms ease;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: 2px solid var(--accent);
  border-color: var(--accent);
}

.form-group textarea {
  min-height: 150px;
  resize: vertical;
}

/* About Page */
.about-hero {
  padding: 80px 0 48px;
}

.about-content {
  padding-bottom: 80px;
}

.about-content p {
  margin-bottom: 24px;
}

/* Mobile Menu */
.mobile-menu {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--bg);
  padding: 32px 24px;
  z-index: 99;
  flex-direction: column;
  gap: 24px;
}

.mobile-menu.open {
  display: flex;
}

.mobile-menu a {
  font-size: 1.25rem;
  font-family: Georgia, 'Times New Roman', serif;
  color: var(--on-bg);
  text-decoration: none;
  padding: 8px 0;
  border-bottom: 1px solid var(--outline-variant);
}

/* Responsive */
@media (max-width: 768px) {
  .display {
    font-size: 2.5rem;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .site-nav {
    display: none;
  }

  .mobile-menu-btn {
    display: block;
  }

  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .section-header {
    flex-direction: column;
    gap: 16px;
    align-items: flex-start;
  }

  .hero {
    padding: 80px 0 48px;
  }

  .site-footer .container {
    flex-direction: column;
    text-align: center;
  }
}

/* Hidden utility */
.hidden {
  display: none !important;
}