*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(900px 480px at 78% -12%, rgba(255, 153, 0, .12), transparent 62%),
    radial-gradient(760px 420px at -8% 72%, rgba(79, 179, 199, .09), transparent 58%),
    var(--bg-0, #0a0908);
  color: var(--fg-2, #d8c29d);
  font-family: "Noto Sans", system-ui, sans-serif;
  font-size: clamp(15px, .9rem + .2vw, 17px);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
.mono { font-family: "Intel One Mono", ui-monospace, monospace; font-variant-numeric: tabular-nums; }
a { color: var(--orange-1, #f3c46c); text-decoration: none; }
a:hover { color: var(--orange-3, #ff9900); }
:focus-visible { outline: 2px solid var(--blue-1, #7ab8ff); outline-offset: 3px; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 clamp(1rem, 4vw, 2.5rem); }
code, pre { font-family: "Intel One Mono", ui-monospace, monospace; }
code {
  border: 1px solid var(--border-warm, #3a2a18);
  border-radius: 6px;
  padding: .08rem .28rem;
  background: rgba(0, 0, 0, .2);
  color: var(--fg-1, #f6d7a7);
}
pre {
  margin: 0;
  overflow-x: auto;
  border: 1px solid var(--border-2, #2a2a2a);
  border-radius: 8px;
  padding: 1rem;
  background: var(--bg-1, #0f0f10);
  color: var(--blue-1, #7ab8ff);
}
header.bar {
  position: sticky; top: 0; z-index: 10;
  background: #15120c;
  border-bottom: 1px solid var(--border-2, #2a2a2a);
}
.bar .wrap { display: flex; align-items: center; gap: 1rem; min-height: 56px; }
.wordmark {
  display: flex; align-items: center; gap: .6rem;
  color: var(--fg-1, #f6d7a7);
  font-weight: 700; letter-spacing: .14em; text-transform: uppercase;
}
.wordmark img { height: 39px; width: auto; display: block; }
footer .wordmark img { height: 22px; }
.bar nav { margin-left: auto; display: flex; align-items: center; gap: .95rem; font-size: .82rem; }
.bar nav a,
.nav-trigger { color: var(--fg-4, #9f9f9f); }
.bar nav a:hover,
.bar nav a.active,
.nav-trigger:hover,
.nav-trigger.active,
.nav-group[open] .nav-trigger { color: var(--orange-1, #f3c46c); }
.nav-group { position: relative; }
.nav-trigger { list-style: none; cursor: pointer; outline-offset: 4px; white-space: nowrap; }
.nav-trigger::-webkit-details-marker { display: none; }
.nav-trigger::after { content: " v"; color: var(--fg-5, #737373); font-size: .72rem; }
.nav-group[open] .nav-trigger::after { content: " ^"; color: var(--orange-1, #f3c46c); }
.nav-menu {
  position: absolute;
  top: calc(100% + .9rem);
  left: 50%;
  z-index: 12;
  min-width: 210px;
  max-height: min(72vh, 520px);
  overflow-y: auto;
  padding: .55rem;
  border: 1px solid var(--border-2, #2a2a2a);
  border-radius: 8px;
  background: #15120c;
  transform: translateX(-50%);
}
.nav-menu a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .75rem;
  padding: .45rem .55rem;
  border-radius: 6px;
  color: var(--fg-3, #d4c19a);
}
.nav-menu a::after { content: "->"; color: var(--fg-5, #737373); }
.nav-menu a:hover { background: var(--bg-2, #121212); }
.hm-btn {
  display: none;
  margin-left: auto;
  border: 0;
  background: none;
  color: var(--fg-2, #d8c29d);
  font-size: 1.2rem;
  line-height: 1;
  cursor: pointer;
}
.hm-btn:hover { color: var(--orange-1, #f3c46c); }
.hm-scrim {
  position: fixed;
  inset: 0;
  z-index: 19;
  background: rgba(0, 0, 0, .5);
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s ease;
}
.hm-scrim.open { opacity: 1; pointer-events: auto; }
.hm-overlay {
  position: fixed;
  top: 0;
  right: 0;
  z-index: 20;
  width: min(86vw, 320px);
  height: 100vh;
  overflow-y: auto;
  padding: 1.5rem;
  background: #15120c;
  border-left: 1px solid var(--border-2, #2a2a2a);
  transform: translateX(100%);
  transition: transform .2s ease;
}
.hm-overlay.open { transform: translateX(0); }
.hm-close {
  position: absolute; top: 1rem; right: 1rem;
  border: 0;
  background: none;
  color: var(--fg-2, #d8c29d);
  cursor: pointer;
  font-size: 1.2rem;
}
.hm-close:hover { color: var(--orange-1, #f3c46c); }
.hm-head {
  margin-top: .5rem;
  margin-bottom: .15rem;
  color: var(--fg-5, #737373);
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.hm-head:first-of-type { margin-top: 2rem; }
.hm-overlay a { display: block; padding: .35rem 0; color: var(--fg-2, #d8c29d); font-size: .85rem; }
.hm-overlay a:hover,
.hm-overlay a.active { color: var(--orange-1, #f3c46c); }
.hero {
  border-bottom: 1px solid var(--border-2, #2a2a2a);
  padding: clamp(2.8rem, 8vw, 5.5rem) 0 clamp(1.8rem, 4vw, 3rem);
}
.crumbs { display: flex; flex-wrap: wrap; gap: .45rem; align-items: center; margin-bottom: .9rem; color: var(--fg-5, #737373); font-size: .78rem; }
.crumbs a { color: var(--fg-4, #9f9f9f); }
.crumbs a:hover { color: var(--orange-1, #f3c46c); }
.crumbs span::before { content: "/"; margin-right: .45rem; color: var(--fg-5, #737373); }
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, .42fr);
  gap: clamp(1.25rem, 4vw, 3rem);
  align-items: end;
}
h1 { margin: 0; max-width: 900px; color: var(--fg-1, #f6d7a7); font-size: clamp(2.2rem, 1.1rem + 5vw, 4.9rem); line-height: 1.04; letter-spacing: 0; }
.lede { max-width: 70ch; margin: 1.1rem 0 0; color: var(--fg-2, #d8c29d); font-family: "Noto Serif", Georgia, serif; font-size: clamp(1.03rem, 1rem + .32vw, 1.22rem); }
.summary-panel {
  border: 1px solid var(--border-warm, #3a2a18);
  border-radius: 8px;
  background: linear-gradient(180deg, rgba(29, 24, 18, .96), rgba(18, 18, 18, .98));
  padding: 1rem;
}
.summary-panel h2 { margin: 0 0 .8rem; color: var(--orange-1, #f3c46c); font-size: .82rem; letter-spacing: .08em; text-transform: uppercase; }
.summary-panel ul { margin: 0; padding: 0; list-style: none; display: grid; gap: .55rem; color: var(--fg-3, #d4c19a); font-size: .9rem; }
.summary-panel li::before { content: "-> "; color: var(--orange-1, #f3c46c); }
.article {
  display: grid;
  grid-template-columns: minmax(180px, .26fr) minmax(0, .74fr);
  gap: clamp(1.25rem, 4vw, 3rem);
  padding: clamp(2rem, 5vw, 3.5rem) 0 clamp(3rem, 7vw, 5rem);
}
.toc { position: sticky; top: 78px; align-self: start; border-left: 1px solid var(--border-warm, #3a2a18); padding-left: 1rem; }
.toc a { display: block; padding: .28rem 0; color: var(--fg-4, #9f9f9f); font-size: .82rem; }
.toc a:hover { color: var(--orange-1, #f3c46c); }
.lesson { display: grid; gap: 1.45rem; min-width: 0; }
.lesson section { border-top: 1px solid var(--border-2, #2a2a2a); padding-top: 1.25rem; }
.lesson section:first-child { border-top: 0; padding-top: 0; }
.lesson h2 { margin: 0 0 .55rem; color: var(--fg-1, #f6d7a7); font-size: clamp(1.28rem, 1rem + 1.4vw, 2rem); }
.lesson h3 { margin: .9rem 0 .35rem; color: var(--blue-1, #7ab8ff); font-size: 1rem; }
.lesson p { margin: .6rem 0 0; }
.lesson ul { margin: .7rem 0 0; padding-left: 1.1rem; }
.lesson li { margin: .35rem 0; }
.callout { border: 1px solid var(--border-warm, #3a2a18); border-radius: 8px; padding: 1rem; background: rgba(29, 24, 18, .75); }
.split { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .8rem; }
.mini-card { border: 1px solid var(--border-2, #2a2a2a); border-radius: 8px; padding: .9rem; background: var(--bg-2, #121212); }
.mini-card strong { display: block; color: var(--orange-1, #f3c46c); margin-bottom: .25rem; }
footer { border-top: 1px solid var(--border-2, #2a2a2a); }
footer .wrap { display: flex; flex-wrap: wrap; gap: 1.2rem 2rem; align-items: center; padding-top: 2rem; padding-bottom: 3rem; }
footer .links { display: flex; flex-wrap: wrap; gap: 1.4rem; font-size: .82rem; }
footer .meta { margin-left: auto; color: var(--fg-5, #737373); font-size: .74rem; }
@media (max-width: 860px) {
  .bar .wrap { min-height: auto; padding-top: .75rem; padding-bottom: .9rem; }
  .bar nav { display: none; }
  .hm-btn { display: block; }
  .hero-grid,
  .article,
  .split { grid-template-columns: 1fr; }
  .toc { position: static; display: flex; flex-wrap: wrap; gap: .25rem .9rem; border-left: 0; border-top: 1px solid var(--border-warm, #3a2a18); padding: 1rem 0 0; }
  footer .meta { margin-left: 0; width: 100%; }
}
@media (max-width: 540px) {
  h1 { font-size: 2rem; }
  .summary-panel,
  .mini-card,
  .callout { padding: .9rem; }
}