/* Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* Variables */
:root {
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-text: #222;
  --color-text-muted: #666;
  --color-accent: #2563eb;
  --color-accent-hover: #1d4ed8;
  --color-border: #e5e5e5;
  --color-code-bg: #f3f4f6;
  --font-sans: system-ui, -apple-system, sans-serif;
  --font-serif: Georgia, 'Times New Roman', serif;
  --font-mono: ui-monospace, 'SFMono-Regular', monospace;
  --max-width: 52rem;
  --spacing: 1.5rem;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --radius: 0.75rem;
  --radius-sm: 0.5rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1a1a1a;
    --color-surface: #242424;
    --color-text: #e5e5e5;
    --color-text-muted: #999;
    --color-accent: #60a5fa;
    --color-accent-hover: #93bbfd;
    --color-border: #333;
    --color-code-bg: #2a2a2a;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.2);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.3);
  }
}

/* Base */
html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--spacing);
}

/* Typography */
h1, h2, h3, h4 {
  line-height: 1.2;
  margin-bottom: 0.5em;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }

p { margin-bottom: 1em; }

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

a:hover {
  text-decoration: underline;
  color: var(--color-accent-hover);
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing);
}

.site-header nav {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--color-text-muted);
  transition: color 0.15s;
}

.nav-links a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.nav-links a[aria-current="page"] {
  color: var(--color-text);
  font-weight: 600;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--spacing);
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing);
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s, transform 0.2s;
  display: flex;
  flex-direction: column;
}

.card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  text-decoration: none;
}

.card-image {
  display: block;
  width: 100%;
  max-width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.card-body {
  padding: var(--spacing);
}

.card h3 {
  margin-bottom: 0.25em;
  color: var(--color-text);
}

.card p {
  color: var(--color-text-muted);
}

.card .meta {
  color: var(--color-text-muted);
  font-size: 0.875rem;
  margin-bottom: 0.5em;
}

/* Prose (article content) */
.content {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.75;
}

.content h2 {
  font-family: var(--font-sans);
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
}

.content h3 {
  font-family: var(--font-sans);
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.content blockquote {
  border-left: 3px solid var(--color-accent);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
  color: var(--color-text-muted);
  font-style: italic;
}

.content pre {
  background: var(--color-code-bg);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin: 1.5rem 0;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
}

.content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--color-code-bg);
  padding: 0.15em 0.4em;
  border-radius: 0.25rem;
}

.content pre code {
  background: none;
  padding: 0;
}

.content ul,
.content ol {
  padding-left: 1.5rem;
  margin-bottom: 1em;
}

.content li {
  margin-bottom: 0.25em;
}

.content hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 2rem 0;
}

.content img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
}

.content a {
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* Responsive */
@media (max-width: 640px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }

  .nav-links {
    gap: 1rem;
    font-size: 0.875rem;
  }

  .content {
    font-size: 1rem;
  }
}