:root {
  --text: #111;
  --text-secondary: #555;
  --text-muted: #777;
  --bg: #fff;
  --bg-code: #f5f5f5;
  --border: #e0e0e0;
  --link: #2563eb;
  --link-hover: #1d4ed8;
}

@media (prefers-color-scheme: dark) {
  :root {
    --text: #e0e0e0;
    --text-secondary: #aaa;
    --text-muted: #888;
    --bg: #1a1a1a;
    --bg-code: #2a2a2a;
    --border: #333;
    --link: #60a5fa;
    --link-hover: #93bbfd;
  }
}

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

html {
  height: 100%;
  font-size: 17px;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100%;
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif;
  font-weight: 400;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.site {
  max-width: 740px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */

.site-header {
  margin-bottom: 2.5rem;
}

.site-name {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--text);
  text-decoration: none;
}

.site-name:hover {
  color: var(--text-secondary);
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1.25rem;
  margin-top: 0.35rem;
}

nav a {
  font-size: 0.85rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s;
}

nav a:hover {
  color: var(--text);
}

.nav-current {
  font-size: 0.85rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* Footer */

.site-footer {
  margin-top: auto;
  padding-top: 2rem;
}

/* Social icons */

.social {
  display: flex;
  gap: 1rem;
}

.social a {
  color: var(--text-muted);
  font-size: 1.1rem;
  transition: color 0.15s;
}

.social a:hover {
  color: var(--text);
}

/* Main content */

main {
  margin-top: 1rem;
}

/* Page heading */

.page-heading {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--text);
  margin-bottom: 1.25rem;
}

/* Post detail */

article .page-heading {
  font-size: 1.6rem;
  font-family: Georgia, "Times New Roman", Times, serif;
  text-transform: none;
  letter-spacing: normal;
}

.post-subtitle {
  font-family: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: -0.75rem;
  margin-bottom: 1rem;
}

.post-meta {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.post-date {
  font-size: 0.95rem;
  cursor: default;
}

.post-updated {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
  font-style: italic;
}

/* Post list */

.post-list {
  list-style: none;
}

.post-list li {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 0.3rem 0;
}

.post-list .meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  min-width: 6rem;
}

.post-list a {
  color: var(--text);
  text-decoration: none;
}

.post-list a:hover {
  color: var(--link);
}

/* Links */

a {
  color: var(--link);
  text-decoration: none;
  transition: color 0.15s;
}

a:hover {
  color: var(--link-hover);
}

/* Markdown / prose content */

.prose h1,
.prose h2,
.prose h3,
.prose h4 {
  font-weight: 700;
  line-height: 1.3;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  color: var(--text);
}

.prose h2 {
  font-size: 1.25rem;
}
.prose h3 {
  font-size: 1.1rem;
}
.prose h4 {
  font-size: 1rem;
}

.prose p {
  margin-bottom: 1rem;
}

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

.prose li {
  list-style-type: disc;
  margin-bottom: 0.25rem;
}

.prose li ul {
  margin-top: 0.25rem;
  margin-bottom: 0.25rem;
}

.prose li li {
  list-style-type: circle;
}

.prose li li li {
  list-style-type: square;
}

.prose em {
  font-style: italic;
}

.prose strong {
  font-weight: 700;
}

.prose blockquote {
  padding: 0.5rem 1rem;
  margin: 1rem 0;
  color: var(--text-muted);
  border-left: 3px solid var(--border);
}

.prose blockquote p:last-child {
  margin-bottom: 0;
}

.prose code,
.prose pre {
  font-family: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
  font-size: 0.9rem;
  background: var(--bg-code);
  border-radius: 3px;
}

.prose code {
  padding: 0.15em 0.4em;
}

.prose pre {
  display: block;
  padding: 1rem;
  margin: 1rem 0 1.5rem;
  line-height: 1.5;
  overflow-x: auto;
  white-space: pre;
}

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

.prose hr {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

.prose img {
  max-width: 100%;
  border-radius: 4px;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
}

.prose td,
.prose th {
  padding: 0.4rem 0.6rem;
  border: 1px solid var(--border);
  text-align: left;
}

.prose tbody tr:nth-child(odd) {
  background: var(--bg-code);
}

/* 404 */

.four-oh-four {
  text-align: center;
  padding: 3rem 0;
}

.four-oh-four .num {
  font-size: 3rem;
  font-weight: 200;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.four-oh-four .detail {
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
}

/* Header photo */

.header-photo {
  width: 100%;
  height: 200px;
  border-radius: 4px;
  margin-bottom: 2rem;
  overflow: hidden;
}

.header-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  display: block;
}

/* Footnotes */

.footnote-ref {
  text-decoration: none;
  font-size: 0.75em;
  cursor: pointer;
}

.fn-tooltip {
  display: none;
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  width: 280px;
  padding: 0.75rem 1rem;
  margin-bottom: 0.5rem;
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--text-secondary);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  z-index: 10;
}

.fn-tooltip.visible {
  display: block;
}

.fn-tooltip p {
  margin-bottom: 0.25rem;
}

.fn-tooltip p:last-child {
  margin-bottom: 0;
}

.prose .footnotes {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.prose .footnotes ol {
  padding-left: 1.25rem;
}

.prose .footnotes li {
  margin-bottom: 0.5rem;
  list-style-type: decimal;
}

/* Responsive */

@media (max-width: 480px) {
  html {
    font-size: 16px;
  }
  .site {
    padding: 2rem 1.25rem;
  }
  .post-list li {
    flex-direction: column;
    gap: 0;
  }
  .post-list .meta {
    min-width: 0;
  }
}