:root {
  --bg: #0b0c10;
  --card: rgba(17, 19, 26, 0.92);
  --text: #e7e7ea;
  --text-strong: #f2f3f8;
  --muted: #b5b6bf;
  --link: #7aa2f7;
  --link-hover: #a5c7ff;
  --border: rgba(255, 255, 255, 0.08);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --radius: 14px;
  --max-width: 78ch;
  --pad: clamp(1.25rem, 2.4vw, 2.25rem);
  --code-bg: rgba(255, 255, 255, 0.06);
  --code-block-bg: rgba(6, 7, 12, 0.70);
  --code-border: rgba(255, 255, 255, 0.10);

  /* Syntax highlighting (Pandoc + Pygments-style tokens). */
  --code-fg: #c8d3f5;
  --code-muted: #6b7396;
  --code-red: #f7768e;
  --code-orange: #ff9e64;
  --code-yellow: #e0af68;
  --code-green: #9ece6a;
  --code-cyan: #2ac3de;
  --code-blue: #7aa2f7;
  --code-purple: #bb9af7;
}

* { box-sizing: border-box; }

html { font-size: 18px; }

body {
  margin: 0;
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", Times, serif;
  line-height: 1.7;
  color: var(--text);
  background: radial-gradient(1200px 800px at 20% 0%, rgba(122, 162, 247, 0.18), transparent 55%),
              radial-gradient(900px 700px at 100% 30%, rgba(36, 204, 142, 0.10), transparent 55%),
              var(--bg);
  min-height: 100vh;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background: rgba(122, 162, 247, 0.28);
}

a { color: var(--link); text-decoration: none; text-underline-offset: 0.14em; }
a:hover { color: var(--link-hover); text-decoration: underline; }

:focus-visible {
  outline: 2px solid rgba(122, 162, 247, 0.75);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0.75rem;
  z-index: 9999;
  padding: 0.55rem 0.75rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(17, 19, 26, 0.98);
  color: var(--text);
}

.skip-link:focus {
  left: var(--pad);
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(11, 12, 16, 0.85);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}

.site-nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.9rem var(--pad);
  display: flex;
  gap: 0.25rem 0.6rem;
  align-items: center;
  flex-wrap: wrap;
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.55rem;
  border-radius: 12px;
  color: var(--muted);
}

.site-nav a:hover {
  text-decoration: none;
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
}

.site-nav a.brand {
  color: var(--text-strong);
  font-weight: 650;
  letter-spacing: 0.01em;
}

.content {
  width: min(var(--max-width), calc(100% - (2 * var(--pad))));
  margin: clamp(1.75rem, 3vw, 2.6rem) auto 1.5rem auto;
  padding: clamp(1.4rem, 3vw, 2.6rem);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.035), transparent 45%), var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.content img { max-width: 100%; height: auto; }
.content img, .content video { border-radius: 10px; }

.content h1, .content h2, .content h3, .content h4 {
  line-height: 1.25;
  margin-top: 1.75em;
  margin-bottom: 0.65em;
  text-wrap: balance;
  scroll-margin-top: 5.5rem;
}

.content h1 { font-size: 2.0rem; margin-top: 0; }
.content h2 { font-size: 1.5rem; }
.content h3 { font-size: 1.25rem; }
.content h2 { padding-bottom: 0.25rem; border-bottom: 1px solid rgba(255, 255, 255, 0.10); }

.content p { margin: 1rem 0; }
.content > :first-child { margin-top: 0; }
.content > :last-child { margin-bottom: 0; }

.content strong, .content b { color: var(--text-strong); }
.content em { color: rgba(231, 231, 234, 0.96); }

.content ul, .content ol { margin: 1rem 0; padding-left: 1.25em; }
.content li { margin: 0.35rem 0; }
.content li > p { margin: 0.55rem 0; }

.content code, .content pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

.content code {
  background: var(--code-bg);
  padding: 0.12em 0.35em;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.09);
}

.content pre {
  background: var(--code-block-bg);
  margin: 1.1rem 0;
  padding: 0.9rem;
  border-radius: 10px;
  overflow-x: auto;
  white-space: pre;
  overflow-wrap: normal;
  word-break: normal;
  tab-size: 2;
  border: 1px solid var(--code-border);
}

.content div.sourceCode {
  margin: 1.1rem 0;
}

.codeblock {
  position: relative;
  margin: 1.1rem 0;
}

.codeblock[data-lang]::before {
  content: attr(data-lang);
  position: absolute;
  top: 0.55rem;
  left: 0.75rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.72rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  color: var(--code-muted);
  user-select: none;
}

.codeblock .code-copy {
  position: absolute;
  top: 0.4rem;
  right: 0.45rem;
  font: inherit;
  font-size: 0.85rem;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--code-border);
  border-radius: 10px;
  padding: 0.25rem 0.55rem;
  cursor: pointer;
}

.codeblock .code-copy:hover {
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
}

.codeblock > pre {
  margin: 0;
  padding-top: 2.25rem;
}

.content pre code {
  color: var(--code-fg);
}

/* Hide Pandoc’s per-line anchor links but keep them for deep-linking. */
.content code.sourceCode > span > a[aria-hidden="true"] {
  display: none;
}

/* Pandoc syntax highlighting token colors (classes from highlight-kate). */
.content code.sourceCode span.kw { color: var(--code-purple); font-weight: 600; }
.content code.sourceCode span.dt { color: var(--code-cyan); }
.content code.sourceCode span.dv,
.content code.sourceCode span.bn,
.content code.sourceCode span.fl { color: var(--code-orange); }
.content code.sourceCode span.ch,
.content code.sourceCode span.st { color: var(--code-green); }
.content code.sourceCode span.co { color: var(--code-muted); font-style: italic; }
.content code.sourceCode span.ot { color: var(--code-blue); }
.content code.sourceCode span.al,
.content code.sourceCode span.er { color: var(--code-red); font-weight: 600; }
.content code.sourceCode span.fu { color: var(--code-blue); }
.content code.sourceCode span.va { color: var(--code-cyan); }
.content code.sourceCode span.bu { color: var(--code-cyan); }
.content code.sourceCode span.op { color: var(--code-cyan); }
.content code.sourceCode span.at { color: var(--code-fg); }
.content code.sourceCode span.pp { color: var(--code-yellow); }
.content code.sourceCode span.in { color: var(--code-yellow); }
.content code.sourceCode span.cn { color: var(--code-orange); }

.content pre.mermaid {
  text-align: left;
  cursor: zoom-in;
}

.content pre.mermaid svg {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
}

.mermaid-modal {
  position: fixed;
  inset: 0;
  padding: clamp(0.75rem, 3vw, 1.5rem);
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.mermaid-modal__panel {
  width: min(1100px, 96vw);
  max-height: 96vh;
  background: rgba(17, 19, 26, 0.98);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.mermaid-modal__toolbar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 0.75rem;
  border-bottom: 1px solid var(--border);
  background: rgba(11, 12, 16, 0.65);
}

.mermaid-modal__toolbar button {
  font: inherit;
  color: var(--text);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.35rem 0.55rem;
  cursor: pointer;
}

.mermaid-modal__toolbar button:hover {
  background: rgba(255, 255, 255, 0.07);
  border-color: rgba(255, 255, 255, 0.14);
}

.mermaid-modal__toolbar .spacer { flex: 1; }

.mermaid-modal__viewport {
  max-height: calc(96vh - 3rem);
  overflow: auto;
  padding: 0.75rem;
}

.mermaid-modal__viewport svg {
  width: 100%;
  height: auto;
  max-width: none;
  display: block;
  margin: 0 auto;
}

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

.content blockquote {
  margin: 1.2rem 0;
  padding: 0.6rem 0.9rem;
  border-left: 3px solid rgba(122, 162, 247, 0.8);
  color: var(--muted);
  background: rgba(255,255,255,0.03);
}

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

.content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2rem 0;
}

.content th, .content td {
  padding: 0.55rem 0.65rem;
  border: 1px solid rgba(255, 255, 255, 0.09);
  vertical-align: top;
}

.content th { text-align: left; color: var(--text-strong); background: rgba(255, 255, 255, 0.03); }

.part-title {
  font-variant: small-caps;
  letter-spacing: 0.04em;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.page-nav {
  max-width: var(--max-width);
  margin: 0 auto 2.5rem auto;
  padding: 0 var(--pad);
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

.prev-link, .next-link {
  display: inline-block;
  padding: 0.6rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: rgba(17, 19, 26, 0.65);
  transition: background 150ms ease, border-color 150ms ease, transform 150ms ease;
}

.prev-link:hover, .next-link:hover {
  background: rgba(17, 19, 26, 0.85);
  border-color: rgba(255, 255, 255, 0.14);
  transform: translateY(-1px);
}

.site-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem var(--pad) 2rem var(--pad);
  color: var(--muted);
}

@media (max-width: 640px) {
  html { font-size: 16px; }

  .site-nav {
    padding: 0.75rem var(--pad);
  }

  .page-nav {
    flex-direction: column;
  }

  .prev-link, .next-link {
    width: 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}