/* ---------- Fonts ---------- */
@font-face {
  font-family: 'Inter';
  src: url('/assets/fonts/Inter-Regular.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Inter';
  src: url('/assets/fonts/Inter-Medium.woff2') format('woff2');
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Inter';
  src: url('/assets/fonts/Inter-SemiBold.woff2') format('woff2');
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Inter';
  src: url('/assets/fonts/Inter-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'JetBrains Mono';
  src: url('/assets/fonts/JetBrainsMono-Regular.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'JetBrains Mono';
  src: url('/assets/fonts/JetBrainsMono-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

/* ---------- Theme tokens ---------- */
:root, [data-theme="dark"] {
  --bg: #0b0c10;
  --surface: #1f2833;
  --surface-elevated: #242e3a;
  --text: #c5c6c7;
  --text-muted: #8892a0;
  --heading: #66fcf1;
  --accent: #45a29e;
  --border: #2a3340;
  --code-bg: #11151a;
  --header-bg: rgba(31, 40, 51, 0.75);
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 4px 24px rgba(0,0,0,0.35);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.25);
  --transition: 0.2s ease;
}

[data-theme="light"] {
  --bg: #fafafa;
  --surface: #ffffff;
  --surface-elevated: #f4f4f5;
  --text: #18181b;
  --text-muted: #52525b;
  --heading: #0e7490;
  --accent: #4338ca;
  --border: #e4e4e7;
  --code-bg: #f4f4f5;
  --header-bg: rgba(255, 255, 255, 0.75);
  --shadow: 0 4px 24px rgba(0,0,0,0.08);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.05);
}

/* ---------- Base ---------- */
* { box-sizing: border-box; margin: 0; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-feature-settings: 'cv11', 'ss01';
  background: var(--bg);
  color: var(--text);
  font-size: clamp(0.95rem, 0.9rem + 0.2vw, 1.05rem);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background var(--transition), color var(--transition);
}

a {
  color: var(--heading);
  text-decoration: none;
  transition: opacity var(--transition);
}
a:hover { opacity: 0.85; text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ---------- Header ---------- */
.site-header {
  padding: 1.1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--header-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--heading);
  transition: opacity var(--transition);
}
.site-brand:hover { opacity: 0.85; text-decoration: none; }
.site-logo {
  width: 32px;
  height: 32px;
  display: block;
  border-radius: 8px;
}
.site-title {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--heading);
  letter-spacing: 0.02em;
}

.site-header nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}
.site-header nav a {
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--text-muted);
  transition: color var(--transition);
}
.site-header nav a:hover { color: var(--heading); opacity: 1; text-decoration: none; }

.theme-toggle {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 999px;
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  cursor: pointer;
  transition: color var(--transition), border-color var(--transition), background var(--transition);
}
.theme-toggle:hover {
  color: var(--heading);
  border-color: var(--accent);
  background: var(--surface-elevated);
}
[data-theme="dark"] .theme-toggle .icon-sun { display: inline; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
[data-theme="light"] .theme-toggle .icon-sun { display: none; }
[data-theme="light"] .theme-toggle .icon-moon { display: inline; }

/* ---------- Layout ---------- */
.page-content {
  max-width: 740px;
  margin: 5.5rem auto 3rem;
  padding: 0 1.5rem;
  min-height: 60vh;
}

h1, h2, h3, h4 { line-height: 1.25; }

/* Generic typography for any markdown page rendered via default layout */
.page-content > h2 {
  color: var(--heading);
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-top: 3rem;
  margin-bottom: 1.25rem;
  scroll-margin-top: 5rem;
}
.page-content > h3 {
  color: var(--heading);
  font-size: 1.2rem;
  font-weight: 600;
  margin-top: 2rem;
  margin-bottom: 0.85rem;
  scroll-margin-top: 5rem;
}
.page-content > p { margin-bottom: 1.1rem; }
.page-content > ul,
.page-content > ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}
.page-content > ul li,
.page-content > ol li { margin-bottom: 0.5rem; }
.page-content a {
  border-bottom: 1px solid color-mix(in srgb, var(--heading) 30%, transparent);
  transition: border-color var(--transition);
}
.page-content a:hover {
  border-color: var(--heading);
  opacity: 1;
  text-decoration: none;
}

/* ---------- Intro block ---------- */
.intro {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}
.intro-eyebrow {
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}
.intro h1 {
  color: var(--heading);
  font-size: clamp(1.75rem, 1.4rem + 1.5vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}
.intro p {
  color: var(--text-muted);
  font-size: 1.05rem;
  line-height: 1.7;
  margin-bottom: 0.75rem;
}
.intro p:last-child { margin-bottom: 0; }

.section-heading {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--heading);
  margin-bottom: 1.5rem;
  letter-spacing: -0.01em;
}

/* ---------- Post list ---------- */
.post-list { list-style: none; padding: 0; }
.post-list li {
  position: relative;
  margin-bottom: 1.25rem;
  padding: 1.25rem 1.5rem 1.25rem 1.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  overflow: hidden;
}
.post-list li::before {
  content: '';
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: linear-gradient(180deg, var(--heading), var(--accent));
}
.post-list li:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  border-color: var(--accent);
}
.post-list h2 {
  margin: 0 0 0.35rem;
  font-size: clamp(1.1rem, 1rem + 0.5vw, 1.3rem);
  font-weight: 600;
}
.post-list h2 a { color: var(--heading); }
.post-list h2 a:hover { opacity: 0.85; text-decoration: none; }
.post-list .post-meta { color: var(--text-muted); font-size: 0.85rem; margin: 0 0 0.5rem; }
.post-list p { color: var(--text-muted); font-size: 0.95rem; line-height: 1.55; margin: 0; }

/* ---------- Post ---------- */
.post-header h1 {
  margin-bottom: 0.35rem;
  color: var(--heading);
  font-size: clamp(1.5rem, 1.2rem + 1vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.01em;
}
.post-meta { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 1.5rem; }

.post-content h2, .post-content h3 {
  color: var(--heading);
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  font-weight: 600;
  position: relative;
  scroll-margin-top: 5rem;
}
.post-content h2 { font-size: 1.4rem; }
.post-content h3 { font-size: 1.15rem; }
.post-content h2[id]:hover::before,
.post-content h3[id]:hover::before {
  content: '#';
  position: absolute;
  left: -1.25rem;
  color: var(--accent);
  font-weight: 400;
  opacity: 0.6;
}
.post-content p { margin-bottom: 1.1rem; }
.post-content pre, .post-content code {
  background: var(--code-bg);
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
}
.post-content code { padding: 0.2rem 0.4rem; }
.post-content pre { padding: 1rem; overflow-x: auto; line-height: 1.5; border: 1px solid var(--border); }
.post-content pre code { padding: 0; background: none; border: 0; }

.post-content .highlight { position: relative; }
.copy-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  padding: 0.25rem 0.6rem;
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition), color var(--transition), border-color var(--transition);
}
.post-content .highlight:hover .copy-btn,
.copy-btn:focus-visible { opacity: 1; }
.copy-btn:hover { color: var(--heading); border-color: var(--accent); }
.copy-btn.copied { color: var(--accent); border-color: var(--accent); }
@media (hover: none) {
  .copy-btn { opacity: 1; }
}
.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
  margin-left: 0;
  color: var(--text-muted);
  font-style: italic;
}
.post-content ul, .post-content ol { margin-bottom: 1.1rem; padding-left: 1.5rem; }
.post-content li { margin-bottom: 0.35rem; }
.post-content a { border-bottom: 1px solid color-mix(in srgb, var(--heading) 30%, transparent); transition: border-color var(--transition); }
.post-content a:hover { border-color: var(--heading); opacity: 1; text-decoration: none; }

.post-content table {
  border-collapse: collapse;
  margin: 1rem 0;
  width: 100%;
}
.post-content th, .post-content td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.75rem;
  text-align: left;
}
.post-content th { background: var(--surface-elevated); }

/* TOC (kramdown {:toc}) */
.post-content .toc, .post-content #markdown-toc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  font-size: 0.9rem;
}

.post-tags { margin-top: 1.5rem; font-size: 0.85rem; color: var(--text-muted); }
.post-tags a {
  background: var(--surface-elevated);
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  display: inline-block;
  margin-right: 0.4rem;
  border: 1px solid var(--border);
  color: var(--text-muted);
  transition: color var(--transition), border-color var(--transition);
}
.post-tags a:hover {
  color: var(--heading);
  border-color: var(--accent);
  text-decoration: none;
  opacity: 1;
}

/* Tag cloud (tags page) */
.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 3rem;
}
.tag-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text);
  font-size: 0.9rem;
  transition: transform var(--transition), border-color var(--transition), color var(--transition);
}
.tag-chip:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  color: var(--heading);
  text-decoration: none;
  opacity: 1;
}
.tag-chip-count {
  background: var(--surface-elevated);
  color: var(--text-muted);
  padding: 0.05rem 0.5rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-variant-numeric: tabular-nums;
}

.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.post-nav-link {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--text);
  transition: transform var(--transition), border-color var(--transition);
}
.post-nav-link:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  opacity: 1;
  text-decoration: none;
}
.post-nav-link.next { text-align: right; }
.post-nav-label { font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.05em; }
.post-nav-title { font-weight: 600; color: var(--heading); }

/* ---------- Footer ---------- */
.site-footer {
  text-align: center;
  padding: 2.5rem 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
}
.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem 0.75rem;
  margin-bottom: 0.75rem;
}
.footer-links a { color: var(--text-muted); font-size: 0.85rem; }
.footer-links a:hover { color: var(--heading); text-decoration: none; opacity: 1; }
.footer-links span { color: var(--border); }
.footer-copy { margin: 0; }

/* ---------- Micro-interactions ---------- */
@media (prefers-reduced-motion: no-preference) {
  .fade-in {
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.5s ease, transform 0.5s ease;
  }
  .fade-in.is-visible {
    opacity: 1;
    transform: none;
  }
}

::view-transition-old(root),
::view-transition-new(root) {
  animation-duration: 0.18s;
}

/* ---------- Responsive ---------- */
@media (max-width: 640px) {
  .site-header { padding: 0.9rem 1rem; }
  .site-header nav { gap: 0.85rem; }
  .page-content { padding: 0 1rem; margin: 1.5rem auto; }
  .post-list li { padding: 1rem 1rem 1rem 1.25rem; }
  .post-nav { grid-template-columns: 1fr; }
}

/* ---------- Syntax highlighting (Rouge) ---------- */
[data-theme="dark"] .highlight table td { padding: 5px; }
[data-theme="dark"] .highlight table pre { margin: 0; }
[data-theme="dark"] .highlight, [data-theme="dark"] .highlight .w {
  color: #f8f8f2;
  background-color: transparent;
}
[data-theme="dark"] .highlight .err { color: #272822; background-color: #f92672; }
[data-theme="dark"] .highlight .c, [data-theme="dark"] .highlight .ch, [data-theme="dark"] .highlight .cd, [data-theme="dark"] .highlight .cm, [data-theme="dark"] .highlight .cpf, [data-theme="dark"] .highlight .c1, [data-theme="dark"] .highlight .cs { color: #75715e; }
[data-theme="dark"] .highlight .cp { color: #f4bf75; }
[data-theme="dark"] .highlight .nt { color: #f4bf75; }
[data-theme="dark"] .highlight .o, [data-theme="dark"] .highlight .ow { color: #f8f8f2; }
[data-theme="dark"] .highlight .p, [data-theme="dark"] .highlight .pi { color: #f8f8f2; }
[data-theme="dark"] .highlight .gi { color: #a6e22e; }
[data-theme="dark"] .highlight .gd { color: #f92672; }
[data-theme="dark"] .highlight .gh { color: #66d9ef; font-weight: bold; }
[data-theme="dark"] .highlight .ge { font-style: italic; }
[data-theme="dark"] .highlight .ges { font-weight: bold; font-style: italic; }
[data-theme="dark"] .highlight .gs { font-weight: bold; }
[data-theme="dark"] .highlight .k, [data-theme="dark"] .highlight .kn, [data-theme="dark"] .highlight .kp, [data-theme="dark"] .highlight .kr, [data-theme="dark"] .highlight .kv { color: #ae81ff; }
[data-theme="dark"] .highlight .kc { color: #fd971f; }
[data-theme="dark"] .highlight .kt { color: #fd971f; }
[data-theme="dark"] .highlight .kd { color: #fd971f; }
[data-theme="dark"] .highlight .s, [data-theme="dark"] .highlight .sb, [data-theme="dark"] .highlight .sc, [data-theme="dark"] .highlight .dl, [data-theme="dark"] .highlight .sd, [data-theme="dark"] .highlight .s2, [data-theme="dark"] .highlight .sh, [data-theme="dark"] .highlight .sx, [data-theme="dark"] .highlight .s1 { color: #a6e22e; }
[data-theme="dark"] .highlight .sa { color: #ae81ff; }
[data-theme="dark"] .highlight .sr { color: #a1efe4; }
[data-theme="dark"] .highlight .si { color: #cc6633; }
[data-theme="dark"] .highlight .se { color: #cc6633; }
[data-theme="dark"] .highlight .nn { color: #f4bf75; }
[data-theme="dark"] .highlight .nc { color: #f4bf75; }
[data-theme="dark"] .highlight .no { color: #f4bf75; }
[data-theme="dark"] .highlight .na { color: #66d9ef; }
[data-theme="dark"] .highlight .m, [data-theme="dark"] .highlight .mb, [data-theme="dark"] .highlight .mf, [data-theme="dark"] .highlight .mh, [data-theme="dark"] .highlight .mi, [data-theme="dark"] .highlight .il, [data-theme="dark"] .highlight .mo, [data-theme="dark"] .highlight .mx { color: #a6e22e; }
[data-theme="dark"] .highlight .ss { color: #a6e22e; }

[data-theme="light"] .highlight table td { padding: 5px; }
[data-theme="light"] .highlight table pre { margin: 0; }
[data-theme="light"] .highlight, [data-theme="light"] .highlight .w { color: #24292f; background-color: transparent; }
[data-theme="light"] .highlight .k, [data-theme="light"] .highlight .kd, [data-theme="light"] .highlight .kn, [data-theme="light"] .highlight .kp, [data-theme="light"] .highlight .kr, [data-theme="light"] .highlight .kt, [data-theme="light"] .highlight .kv { color: #cf222e; }
[data-theme="light"] .highlight .gr { color: #f6f8fa; }
[data-theme="light"] .highlight .gd { color: #82071e; background-color: #ffebe9; }
[data-theme="light"] .highlight .nb { color: #953800; }
[data-theme="light"] .highlight .nc { color: #953800; }
[data-theme="light"] .highlight .no { color: #953800; }
[data-theme="light"] .highlight .nn { color: #953800; }
[data-theme="light"] .highlight .sr { color: #116329; }
[data-theme="light"] .highlight .na { color: #116329; }
[data-theme="light"] .highlight .nt { color: #116329; }
[data-theme="light"] .highlight .gi { color: #116329; background-color: #dafbe1; }
[data-theme="light"] .highlight .ges { font-weight: bold; font-style: italic; }
[data-theme="light"] .highlight .kc { color: #0550ae; }
[data-theme="light"] .highlight .l, [data-theme="light"] .highlight .ld, [data-theme="light"] .highlight .m, [data-theme="light"] .highlight .mb, [data-theme="light"] .highlight .mf, [data-theme="light"] .highlight .mh, [data-theme="light"] .highlight .mi, [data-theme="light"] .highlight .il, [data-theme="light"] .highlight .mo, [data-theme="light"] .highlight .mx { color: #0550ae; }
[data-theme="light"] .highlight .sb { color: #0550ae; }
[data-theme="light"] .highlight .bp { color: #0550ae; }
[data-theme="light"] .highlight .ne { color: #0550ae; }
[data-theme="light"] .highlight .nl { color: #0550ae; }
[data-theme="light"] .highlight .py { color: #0550ae; }
[data-theme="light"] .highlight .nv, [data-theme="light"] .highlight .vc, [data-theme="light"] .highlight .vg, [data-theme="light"] .highlight .vi, [data-theme="light"] .highlight .vm { color: #0550ae; }
[data-theme="light"] .highlight .o, [data-theme="light"] .highlight .ow { color: #0550ae; }
[data-theme="light"] .highlight .gh { color: #0550ae; font-weight: bold; }
[data-theme="light"] .highlight .gu { color: #0550ae; font-weight: bold; }
[data-theme="light"] .highlight .s, [data-theme="light"] .highlight .sa, [data-theme="light"] .highlight .sc, [data-theme="light"] .highlight .dl, [data-theme="light"] .highlight .sd, [data-theme="light"] .highlight .s2, [data-theme="light"] .highlight .se, [data-theme="light"] .highlight .sh, [data-theme="light"] .highlight .sx, [data-theme="light"] .highlight .s1, [data-theme="light"] .highlight .ss { color: #0a3069; }
[data-theme="light"] .highlight .nd { color: #8250df; }
[data-theme="light"] .highlight .nf, [data-theme="light"] .highlight .fm { color: #8250df; }
[data-theme="light"] .highlight .err { color: #f6f8fa; background-color: #82071e; }
[data-theme="light"] .highlight .c, [data-theme="light"] .highlight .ch, [data-theme="light"] .highlight .cd, [data-theme="light"] .highlight .cm, [data-theme="light"] .highlight .cp, [data-theme="light"] .highlight .cpf, [data-theme="light"] .highlight .c1, [data-theme="light"] .highlight .cs { color: #6e7781; }
[data-theme="light"] .highlight .gl { color: #6e7781; }
[data-theme="light"] .highlight .gt { color: #6e7781; }
[data-theme="light"] .highlight .ni { color: #24292f; }
[data-theme="light"] .highlight .si { color: #24292f; }
[data-theme="light"] .highlight .ge { color: #24292f; font-style: italic; }
[data-theme="light"] .highlight .gs { color: #24292f; font-weight: bold; }