/* ── Variables ──────────────────────────────────────────────────────────── */

:root {
  --bg: #fafaf8;
  --bg-alt: #eaeef8;
  --bg-code: #e8eef8;
  --header-bg: rgba(250,250,248,0.92);
  --border: #ddd5cc;
  --text: #1c1c1c;
  --text-muted: #6b6458;
  --link: #002366;
  --link-hover: #001444;
  --accent: #002366;
  --tag-bg: #e8eef8;
  --tag-text: #002366;
  --font: "Merriweather", Georgia, "Times New Roman", serif;
  --font-heading: "Merriweather", Georgia, "Times New Roman", serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --radius: 4px;
  --transition: 140ms ease;
}

[data-theme="dark"] {
  --bg: #1a1816;
  --bg-alt: #0d1a2e;
  --bg-code: #091526;
  --header-bg: rgba(26,24,22,0.92);
  --border: #3d3830;
  --text: #f0ece8;
  --text-muted: #9e9488;
  --link: #6699cc;
  --link-hover: #88b0dc;
  --accent: #6699cc;
  --tag-bg: #0d1f3c;
  --tag-text: #6699cc;
}

/* ── Reset ──────────────────────────────────────────────────────────────── */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

/* ── Base ───────────────────────────────────────────────────────────────── */

body {
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text);
  background: var(--bg);
  transition: background var(--transition), color var(--transition);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a { color: var(--link); text-decoration: none; }
a:hover { color: var(--link-hover); text-decoration: underline; }

h1,h2,h3,h4,h5,h6 {
  font-family: var(--font-heading);
  line-height: 1.25;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  color: var(--text);
}
h1 { font-size: 1.875rem; letter-spacing: -.02em; }
h2 { font-size: 1.375rem; letter-spacing: -.01em; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }
h1:first-child, h2:first-child, h3:first-child { margin-top: 0; }

p { margin-bottom: 1.25rem; }

ul, ol { margin-bottom: 1.25rem; padding-left: 1.5rem; }
li { margin-bottom: .375rem; }

blockquote {
  border-left: 3px solid var(--accent);
  padding: .75rem 1.25rem;
  margin: 1.5rem 0;
  color: var(--text-muted);
  background: var(--bg-alt);
  border-radius: 0 var(--radius) var(--radius) 0;
}
blockquote p:last-child { margin-bottom: 0; }

code {
  font-family: var(--mono);
  font-size: .875em;
  background: var(--bg-code);
  padding: .1em .4em;
  border-radius: 4px;
}

pre {
  font-family: var(--mono);
  font-size: .875rem;
  line-height: 1.6;
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.125rem 1.5rem;
  overflow-x: auto;
  margin: 1.5rem 0;
}
pre code { background: none; padding: 0; font-size: inherit; }

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

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

table { width: 100%; border-collapse: collapse; margin: 1.5rem 0; font-size: .9375rem; }
th,td { padding: .5rem 1rem; border: 1px solid var(--border); text-align: left; }
th { background: var(--bg-alt); font-weight: 600; }
tr:nth-child(even) td { background: var(--bg-alt); }

::selection { background: var(--accent); color: #fff; }

/* ── Layout ─────────────────────────────────────────────────────────────── */

.container { max-width: 740px; margin: 0 auto; padding: 0 1.5rem; }

header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
}

.header-inner {
  max-width: 740px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -.01em;
  white-space: nowrap;
}
.site-title:hover { color: var(--accent); text-decoration: none; }

nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

nav a {
  font-size: .9375rem;
  font-weight: 500;
  color: var(--text-muted);
}
nav a:hover { color: var(--text); text-decoration: none; }

main { flex: 1; padding: 3rem 0; }

footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  transition: border-color var(--transition);
}

.footer-inner {
  max-width: 740px;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: .875rem;
  color: var(--text-muted);
}

.footer-links { display: flex; gap: 1.25rem; }
.footer-links a { color: var(--text-muted); }
.footer-links a:hover { color: var(--text); text-decoration: none; }

/* ── Theme Toggle ───────────────────────────────────────────────────────── */

#theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: color var(--transition), background var(--transition);
  padding: 0;
  flex-shrink: 0;
}
#theme-toggle:hover { color: var(--text); background: var(--bg-alt); }

.icon-sun  { display: none; }
.icon-moon { display: block; }
[data-theme="dark"] .icon-sun  { display: block; }
[data-theme="dark"] .icon-moon { display: none; }

/* ── Post Card (homepage) ───────────────────────────────────────────────── */

.post-card { padding: 2rem 0; border-bottom: 1px solid var(--border); }
.post-card:first-child { padding-top: 0; }
.post-card:last-child { border-bottom: none; }

.post-meta {
  display: flex;
  gap: .75rem;
  font-size: .875rem;
  color: var(--text-muted);
  margin-bottom: .5rem;
}

.post-card h2 { font-size: 1.3125rem; margin: 0 0 .5rem; }
.post-card h2 a { color: var(--text); }
.post-card h2 a:hover { color: var(--accent); text-decoration: none; }

.excerpt { color: var(--text-muted); font-size: .9375rem; margin-bottom: .875rem; }

/* ── Tags ───────────────────────────────────────────────────────────────── */

.tags { display: flex; flex-wrap: wrap; gap: .375rem; }

.tag {
  display: inline-flex;
  align-items: center;
  padding: .2em .75em;
  background: var(--tag-bg);
  color: var(--tag-text);
  border-radius: 9999px;
  font-size: .8125rem;
  font-weight: 500;
}
.tag:hover { opacity: .75; text-decoration: none; color: var(--tag-text); }

/* ── Pagination ─────────────────────────────────────────────────────────── */

.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  font-size: .9375rem;
}

.pagination a,
.pagination span {
  padding: .375rem .875rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
}
.pagination a:hover { background: var(--bg-alt); text-decoration: none; color: var(--text); }
.pagination .disabled { color: var(--text-muted); opacity: .45; cursor: default; }

/* ── Post Page ──────────────────────────────────────────────────────────── */

.back-link {
  display: inline-flex;
  align-items: center;
  gap: .375rem;
  font-size: .9375rem;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 2rem;
}
.back-link::before { content: "←"; }
.back-link:hover { color: var(--text); text-decoration: none; }

.post-header { margin-bottom: 1.75rem; }
.post-header h1 { font-size: 2.125rem; line-height: 1.2; margin: .5rem 0 1rem; }
.post-header .post-meta { margin-bottom: .75rem; }

.post-content > *:first-child { margin-top: 0; }

/* ── Tags Page ──────────────────────────────────────────────────────────── */

.all-tags { display: flex; flex-wrap: wrap; gap: .5rem; margin: 1.5rem 0 2.5rem; }

.tag-section { margin-bottom: 2.5rem; }
.tag-section h2 {
  font-size: .8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--text-muted);
  margin: 0 0 .75rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--border);
}

.tag-section ul { list-style: none; padding: 0; margin: 0; }

.tag-post-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  padding: .625rem 0;
  border-bottom: 1px solid var(--border);
}
.tag-post-item:last-child { border-bottom: none; }
.tag-post-item a { font-weight: 500; color: var(--text); flex: 1; }
.tag-post-item a:hover { color: var(--accent); text-decoration: none; }
.tag-post-item time { font-size: .875rem; color: var(--text-muted); white-space: nowrap; }

.muted { color: var(--text-muted); text-align: center; padding: 3rem 0; }

/* ── Syntax Highlighting ────────────────────────────────────────────────── */

.highlight { border-radius: var(--radius); overflow: hidden; margin: 1.5rem 0; border: 1px solid var(--border); }
.highlight pre { margin: 0; border: none; border-radius: 0; }

.highlight .c,.highlight .cm,.highlight .c1,.highlight .cs { color:#6a737d; font-style:italic }
.highlight .k,.highlight .kc,.highlight .kd,.highlight .kn,.highlight .kp,.highlight .kr { color:#7c3aed; font-weight:bold }
.highlight .o,.highlight .ow,.highlight .kt { color:#0e7490 }
.highlight .m,.highlight .mi,.highlight .mf { color:#d97706 }
.highlight .s,.highlight .s1,.highlight .s2,.highlight .sb,.highlight .sc,.highlight .se,.highlight .sh,.highlight .si,.highlight .sr,.highlight .ss { color:#059669 }
.highlight .na,.highlight .nf { color:#2563eb }
.highlight .nb { color:#0e7490 }
.highlight .nc,.highlight .no,.highlight .nd { color:#d97706; font-weight:bold }
.highlight .nt { color:#7c3aed }
.highlight .gd { color:#b91c1c; background:#fee2e2 }
.highlight .gi { color:#15803d; background:#dcfce7 }

[data-theme="dark"] .highlight .c,
[data-theme="dark"] .highlight .cm,
[data-theme="dark"] .highlight .c1,
[data-theme="dark"] .highlight .cs { color:#8b949e }
[data-theme="dark"] .highlight .k,
[data-theme="dark"] .highlight .kc,
[data-theme="dark"] .highlight .kd,
[data-theme="dark"] .highlight .kn,
[data-theme="dark"] .highlight .kp,
[data-theme="dark"] .highlight .kr { color:#c084fc }
[data-theme="dark"] .highlight .o,
[data-theme="dark"] .highlight .ow,
[data-theme="dark"] .highlight .kt { color:#67e8f9 }
[data-theme="dark"] .highlight .m,
[data-theme="dark"] .highlight .mi,
[data-theme="dark"] .highlight .mf { color:#f59e0b }
[data-theme="dark"] .highlight .s,
[data-theme="dark"] .highlight .s1,
[data-theme="dark"] .highlight .s2,
[data-theme="dark"] .highlight .sb,
[data-theme="dark"] .highlight .sc,
[data-theme="dark"] .highlight .se,
[data-theme="dark"] .highlight .sh,
[data-theme="dark"] .highlight .si,
[data-theme="dark"] .highlight .sr,
[data-theme="dark"] .highlight .ss { color:#86efac }
[data-theme="dark"] .highlight .na,
[data-theme="dark"] .highlight .nf { color:#60a5fa }
[data-theme="dark"] .highlight .nb { color:#67e8f9 }
[data-theme="dark"] .highlight .nc,
[data-theme="dark"] .highlight .no,
[data-theme="dark"] .highlight .nd { color:#fbbf24 }
[data-theme="dark"] .highlight .nt { color:#c084fc }
[data-theme="dark"] .highlight .gd { color:#fca5a5; background:#450a0a }
[data-theme="dark"] .highlight .gi { color:#86efac; background:#052e16 }

/* ── Responsive ─────────────────────────────────────────────────────────── */

@media (max-width: 600px) {
  .post-header h1 { font-size: 1.625rem; }
  nav { gap: .875rem; }
  main { padding: 2rem 0; }
}