/* Learn SkrillaPlan — dark-first, zero external requests, system fonts only.
   Motif: an old typewriter and a money clip on the same desk. */

:root {
  --bg: #16130e;
  --bg-raised: #1e1a13;
  --ink: #e9e2d3;
  --ink-soft: #b3a98f;
  --accent: #d8a93d;
  --accent-ink: #16130e;
  --rule: #35301f;
  --link: #e6c979;
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
  --body: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg: #faf6ec;
    --bg-raised: #f1ebdc;
    --ink: #241f14;
    --ink-soft: #6b6250;
    --accent: #9a7415;
    --accent-ink: #faf6ec;
    --rule: #ddd3bc;
    --link: #7d5f0e;
  }
}
:root[data-theme="light"] {
  --bg: #faf6ec;
  --bg-raised: #f1ebdc;
  --ink: #241f14;
  --ink-soft: #6b6250;
  --accent: #9a7415;
  --accent-ink: #faf6ec;
  --rule: #ddd3bc;
  --link: #7d5f0e;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 1.0625rem;
  line-height: 1.65;
}

/* Header */
.site-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  padding: 0.9rem 1.25rem;
  border-bottom: 1px solid var(--rule);
}
.wordmark {
  white-space: nowrap;
  font-family: var(--mono);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: 0.02em;
}
.wordmark span { color: var(--accent); }
.wordmark em { font-style: normal; font-weight: 400; color: var(--ink-soft); }
.header-links { display: flex; align-items: baseline; gap: 1rem; }
.header-links a {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.9rem;
  font-family: var(--mono);
  white-space: nowrap;
}
.header-links a:hover { color: var(--link); }
#theme-toggle {
  background: none;
  border: 1px solid var(--rule);
  border-radius: 6px;
  color: var(--ink-soft);
  font-size: 0.85rem;
  padding: 0.15rem 0.5rem;
  cursor: pointer;
  white-space: nowrap;
}
#theme-toggle:hover { color: var(--ink); border-color: var(--ink-soft); }

/* Shell */
.shell {
  display: grid;
  grid-template-columns: 15rem minmax(0, 1fr);
  max-width: 66rem;
  margin: 0 auto;
  min-height: calc(100vh - 8rem);
}

/* Sidebar */
.sidebar {
  padding: 1.75rem 1rem 2rem 1.25rem;
  border-right: 1px solid var(--rule);
  font-size: 0.92rem;
}
.sidenav summary { display: none; }
.nav-group {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-soft);
  margin: 1.4rem 0 0.4rem;
}
.nav-group:first-child { margin-top: 0; }
.sidebar ul { list-style: none; margin: 0; padding: 0; }
.sidebar li { margin: 0.1rem 0; }
.sidebar a {
  display: block;
  padding: 0.22rem 0.55rem;
  border-radius: 6px;
  color: var(--ink);
  text-decoration: none;
}
.sidebar a:hover { background: var(--bg-raised); }
.sidebar a[aria-current="page"] {
  background: var(--bg-raised);
  color: var(--link);
  font-weight: 600;
}

/* Content */
.content {
  padding: 1.9rem 2.25rem 3.5rem;
  max-width: 46rem;
}
.content h1, .content h2, .content h3 {
  font-family: var(--mono);
  line-height: 1.25;
  letter-spacing: -0.01em;
}
.content h1 { font-size: 1.7rem; margin: 0.4rem 0 1rem; }
.content h2 {
  font-size: 1.18rem;
  margin: 2.2rem 0 0.6rem;
  padding-top: 1.1rem;
  border-top: 1px solid var(--rule);
}
.content h3 { font-size: 1.02rem; margin: 1.6rem 0 0.4rem; }
.content a { color: var(--link); text-decoration-thickness: 1px; text-underline-offset: 2px; }
.content strong { color: var(--ink); }
.content ul, .content ol { padding-left: 1.35rem; }
.content li { margin: 0.3rem 0; }
.content blockquote {
  margin: 1.2rem 0;
  padding: 0.1rem 1.1rem;
  border-left: 3px solid var(--accent);
  background: var(--bg-raised);
  border-radius: 0 8px 8px 0;
  color: var(--ink-soft);
}
.content code {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--bg-raised);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 0.08em 0.35em;
}
.content hr { border: 0; border-top: 1px solid var(--rule); margin: 2rem 0; }
.content table { border-collapse: collapse; width: 100%; display: block; overflow-x: auto; }
.content th, .content td { border: 1px solid var(--rule); padding: 0.4rem 0.7rem; text-align: left; }

/* Landing extras */
.lede {
  font-size: 1.2rem;
  color: var(--ink-soft);
  margin-bottom: 1.6rem;
}
.cta {
  display: inline-block;
  font-family: var(--mono);
  font-weight: 700;
  background: var(--accent);
  color: var(--accent-ink) !important;
  text-decoration: none !important;
  padding: 0.55rem 1.1rem;
  border-radius: 8px;
}
.cta:hover { filter: brightness(1.08); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 1.25rem;
  text-align: center;
  color: var(--ink-soft);
  font-size: 0.85rem;
  font-family: var(--mono);
}
.site-footer a { color: var(--link); }
.site-footer p { margin: 0.3rem 0; }

/* Mobile */
@media (max-width: 720px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar {
    border-right: 0;
    border-bottom: 1px solid var(--rule);
    padding: 0;
  }
  .sidenav summary {
    display: block;
    list-style: none;
    font-family: var(--mono);
    font-size: 0.85rem;
    letter-spacing: 0.06em;
    color: var(--ink-soft);
    padding: 0.85rem 1.25rem;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
  }
  .sidenav summary::-webkit-details-marker { display: none; }
  .sidenav summary::after { content: "  ▾"; }
  .sidenav[open] summary::after { content: "  ▴"; }
  .sidenav nav { padding: 0 1.25rem 1rem; }
  .sidebar a { padding: 0.5rem 0.55rem; }
  .content { padding: 1.5rem 1.25rem 3rem; }
}

@media (max-width: 400px) {
  .wordmark em { display: none; }
}