/* ─────────────────────────────────────────────────────────────
   Blitsen — documentation site
   The palette, type pairing and datasheet treatment are inherited
   from docs/product.html: paper and ink, ultramarine accent, a
   serif measure with mono display type. Formal, ruled, unhurried —
   the register of the crest the project is named for.
   ───────────────────────────────────────────────────────────── */

:root {
  color-scheme: light;

  --paper:        #E7E6E1;
  --raised:       #F3F2EE;
  --sunken:       #DEDDD7;
  --ink:          #16171A;
  --ink-soft:     #5B5D63;
  --ink-faint:    #86878C;
  --rule:         #CBC9C2;
  --rule-soft:    #DAD8D1;
  --accent:       #2B44C7;
  --accent-deep:  #1E31A0;
  --accent-wash:  #DCE0F8;
  --accent-line:  #A9B4EE;

  --ok:           #1E6B4A;
  --ok-bg:        #D7E7DE;

  --shadow: 0 1px 0 rgba(22, 23, 26, .05);

  --font-mono: ui-monospace, "SFMono-Regular", "JetBrains Mono", "Cascadia Mono",
               Menlo, Consolas, "DejaVu Sans Mono", monospace;
  --font-serif: "Iowan Old Style", Charter, "Palatino Linotype", Palatino, Georgia,
                "Liberation Serif", "DejaVu Serif", serif;

  --measure: 67ch;
  --rail: 15.5rem;
  --toc: 14rem;
  --mast: 3.5rem;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --dark: 1; }
}
:root[data-theme="dark"] { --dark: 1; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --paper: #16171A; --raised: #1E2024; --sunken: #101114;
    --ink: #E9E8E3; --ink-soft: #9B9DA4; --ink-faint: #74767D;
    --rule: #2E3138; --rule-soft: #24262B;
    --accent: #7B92FF; --accent-deep: #A5B4FF;
    --accent-wash: #1E2445; --accent-line: #3A4470;
    --ok: #58BF92; --ok-bg: #122C22;
    --shadow: 0 1px 0 rgba(0, 0, 0, .35);
  }
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #16171A; --raised: #1E2024; --sunken: #101114;
  --ink: #E9E8E3; --ink-soft: #9B9DA4; --ink-faint: #74767D;
  --rule: #2E3138; --rule-soft: #24262B;
  --accent: #7B92FF; --accent-deep: #A5B4FF;
  --accent-wash: #1E2445; --accent-line: #3A4470;
  --ok: #58BF92; --ok-bg: #122C22;
  --shadow: 0 1px 0 rgba(0, 0, 0, .35);
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--mast) + 1.5rem); }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: 1.0625rem;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-underline-offset: .16em; text-decoration-thickness: .06em; }
a:hover { color: var(--accent-deep); }

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--accent); color: #fff; padding: .6rem 1rem;
}
.skip:focus { left: 0; }

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

/* ── masthead ───────────────────────────────────────────────── */

.masthead {
  grid-area: mast;
  position: sticky; top: 0; z-index: 40;
  display: flex; align-items: center; gap: 1.5rem;
  height: var(--mast);
  padding: 0 1.25rem;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule);
}
.brand { display: flex; align-items: center; gap: .6rem; text-decoration: none; color: var(--ink); }
.brand-crest { width: 1.6rem; height: 1.6rem; color: var(--ink); flex: none; }
.brand-name {
  font-family: var(--font-mono); font-size: .95rem; font-weight: 600;
  letter-spacing: .1em; text-transform: uppercase;
}
.top { display: flex; gap: 1.25rem; margin-left: auto; }
.top a {
  font-family: var(--font-mono); font-size: .74rem; letter-spacing: .08em;
  text-transform: uppercase; color: var(--ink-soft); text-decoration: none;
}
.top a:hover { color: var(--accent); }
.mast-actions { display: flex; gap: .35rem; }
.icon-btn {
  display: grid; place-items: center; width: 2rem; height: 2rem;
  background: none; border: 1px solid var(--rule); border-radius: 3px;
  color: var(--ink-soft); cursor: pointer;
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent-line); }
.nav-only { display: none; }

/* ── documentation frame ────────────────────────────────────── */

body.with-rail {
  display: grid;
  grid-template-columns: var(--rail) minmax(0, 1fr) var(--toc);
  grid-template-areas: "mast mast mast" "rail main toc" "foot foot foot";
  align-items: start;
}

.rail {
  grid-area: rail;
  position: sticky; top: var(--mast);
  max-height: calc(100vh - var(--mast));
  overflow-y: auto;
  padding: 2rem 1rem 3rem 1.25rem;
  border-right: 1px solid var(--rule);
}
.rail-group + .rail-group { margin-top: 1.6rem; }
.rail h2 {
  margin: 0 0 .5rem;
  font-family: var(--font-mono); font-size: .68rem; font-weight: 600;
  letter-spacing: .12em; text-transform: uppercase; color: var(--ink-faint);
}
.rail ul { list-style: none; margin: 0; padding: 0; }
.rail li a {
  display: block; padding: .22rem 0 .22rem .7rem;
  border-left: 2px solid var(--rule-soft);
  font-size: .95rem; color: var(--ink-soft); text-decoration: none;
}
.rail li a:hover { color: var(--accent); border-left-color: var(--accent-line); }
.rail li a[aria-current="page"] {
  color: var(--accent); border-left-color: var(--accent); font-weight: 600;
}

main.doc { grid-area: main; padding: 2.5rem 3rem 5rem; min-width: 0; }

.toc {
  grid-area: toc;
  position: sticky; top: var(--mast);
  max-height: calc(100vh - var(--mast));
  overflow-y: auto;
  padding: 2.5rem 1.25rem 3rem 0;
}
.toc h2 {
  margin: 0 0 .55rem;
  font-family: var(--font-mono); font-size: .68rem; font-weight: 600;
  letter-spacing: .12em; text-transform: uppercase; color: var(--ink-faint);
}
.toc ul { list-style: none; margin: 0; padding: 0; border-left: 1px solid var(--rule); }
.toc li a {
  display: block; padding: .18rem 0 .18rem .7rem;
  font-size: .82rem; line-height: 1.4; color: var(--ink-soft); text-decoration: none;
}
.toc li.d3 a { padding-left: 1.5rem; font-size: .78rem; color: var(--ink-faint); }
.toc li a:hover { color: var(--accent); }

/* ── prose ──────────────────────────────────────────────────── */

.prose { max-width: var(--measure); }
.crumb {
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .08em;
  text-transform: uppercase; color: var(--ink-faint); margin: 0 0 1.5rem;
}
.crumb a { color: var(--ink-soft); text-decoration: none; }
.crumb a:hover { color: var(--accent); }

.prose h1 {
  margin: 0 0 1.2rem;
  font-family: var(--font-mono); font-size: 1.85rem; font-weight: 600;
  line-height: 1.2; letter-spacing: -.01em;
}
.prose h2 {
  margin: 2.8rem 0 .9rem; padding-top: .9rem;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono); font-size: 1.22rem; font-weight: 600; line-height: 1.3;
}
.prose h3 {
  margin: 2rem 0 .6rem;
  font-family: var(--font-mono); font-size: 1.02rem; font-weight: 600;
}
.prose h4, .prose h5, .prose h6 {
  margin: 1.5rem 0 .5rem;
  font-family: var(--font-mono); font-size: .9rem; font-weight: 600;
  letter-spacing: .04em; color: var(--ink-soft);
}
.prose p { margin: 0 0 1.05rem; }
.prose ul, .prose ol { margin: 0 0 1.15rem; padding-left: 1.35rem; }
.prose li { margin: .3rem 0; }
.prose li::marker { color: var(--ink-faint); }
.prose ul.tasks { list-style: none; padding-left: .1rem; }
.prose li.task { display: flex; gap: .6rem; align-items: baseline; }
.prose li.task input { accent-color: var(--accent); }

.anchor {
  margin-left: .45rem; color: var(--ink-faint); text-decoration: none;
  opacity: 0; font-weight: 400;
}
h2:hover .anchor, h3:hover .anchor, h4:hover .anchor, .anchor:focus { opacity: 1; }

.prose blockquote {
  margin: 1.4rem 0; padding: .9rem 1.15rem;
  background: var(--accent-wash);
  border-left: 3px solid var(--accent);
}
.prose blockquote p:last-child { margin-bottom: 0; }

.prose hr { margin: 2.4rem 0; border: 0; border-top: 1px solid var(--rule); }

code {
  font-family: var(--font-mono); font-size: .855em;
  background: var(--sunken); border: 1px solid var(--rule-soft);
  border-radius: 3px; padding: .05em .22em;
  overflow-wrap: break-word;
}

figure.code {
  position: relative; margin: 1.4rem 0;
  background: var(--raised); border: 1px solid var(--rule);
  border-radius: 4px; box-shadow: var(--shadow);
}
figure.code pre { margin: 0; padding: .95rem 1.1rem; overflow-x: auto; }
figure.code code {
  background: none; border: 0; padding: 0;
  font-size: .855rem; line-height: 1.6; color: var(--ink);
}
.code-lang {
  position: absolute; top: 0; right: 0;
  padding: .18rem .5rem;
  font-family: var(--font-mono); font-size: .62rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-faint);
  background: var(--sunken); border-left: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule); border-radius: 0 4px 0 4px;
}

.table-scroll { margin: 1.4rem 0; overflow-x: auto; border: 1px solid var(--rule); border-radius: 4px; }
table { width: 100%; border-collapse: collapse; font-size: .92rem; }
caption {
  caption-side: top; padding: .7rem .9rem; text-align: left;
  font-size: .84rem; color: var(--ink-soft); border-bottom: 1px solid var(--rule);
}
th, td { padding: .5rem .8rem; text-align: left; vertical-align: top; }
thead th {
  background: var(--sunken);
  font-family: var(--font-mono); font-size: .72rem; font-weight: 600;
  letter-spacing: .07em; text-transform: uppercase; color: var(--ink-soft);
  border-bottom: 1px solid var(--rule);
}
tbody tr + tr td { border-top: 1px solid var(--rule-soft); }
td .num, th.num, td.num { text-align: right; font-variant-numeric: tabular-nums; }
tr.mine { background: var(--accent-wash); }
tr.mine td { font-weight: 600; }

figure.shot { margin: 1.8rem 0; }
figure.shot img {
  display: block; width: 100%; height: auto;
  border: 1px solid var(--rule); border-radius: 4px; background: var(--raised);
}
figcaption {
  margin-top: .6rem; font-size: .86rem; line-height: 1.5; color: var(--ink-soft);
}

/* ── landing ────────────────────────────────────────────────── */

body.landing { display: block; }
main.home { max-width: 62rem; margin: 0 auto; padding: 0 1.5rem 5rem; }

.hero { padding: 4.5rem 0 3.5rem; text-align: center; }
.hero-crest { width: 6.5rem; height: 6.5rem; color: var(--ink); margin-bottom: 1.2rem; }
.eyebrow {
  margin: 0 0 .8rem;
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .16em;
  text-transform: uppercase; color: var(--ink-faint);
}
.hero h1 {
  margin: 0 0 1rem;
  font-family: var(--font-mono); font-size: clamp(2.4rem, 7vw, 3.6rem);
  font-weight: 600; letter-spacing: -.02em; line-height: 1;
}
.lede { margin: 0 auto 1rem; max-width: 34rem; font-size: 1.28rem; line-height: 1.45; }
.sub { margin: 0 auto 2rem; max-width: 40rem; color: var(--ink-soft); font-size: 1.02rem; }
.cta { display: flex; gap: .75rem; justify-content: center; flex-wrap: wrap; margin-bottom: 2.2rem; }
.btn {
  display: inline-block; padding: .6rem 1.2rem;
  font-family: var(--font-mono); font-size: .8rem; letter-spacing: .06em;
  text-transform: uppercase; text-decoration: none;
  color: var(--ink); background: var(--raised);
  border: 1px solid var(--rule); border-radius: 3px;
}
.btn:hover { border-color: var(--accent-line); color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-deep); border-color: var(--accent-deep); color: #fff; }
.hero-code { max-width: 26rem; margin-inline: auto; text-align: left; }
.fineprint {
  margin: 1rem auto 0; max-width: 40rem;
  font-size: .84rem; line-height: 1.55; color: var(--ink-faint);
}

.band { padding: 3.2rem 0; border-top: 1px solid var(--rule); }
.band > h2 {
  margin: 0 0 1rem;
  font-family: var(--font-mono); font-size: 1.5rem; font-weight: 600; letter-spacing: -.01em;
}
.band-lede { max-width: var(--measure); font-size: 1.1rem; margin: 0 0 1rem; }
.band-note { max-width: var(--measure); color: var(--ink-soft); margin: 0 0 1rem; }

.grid-3 { display: grid; gap: 1.5rem; grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr)); }
.grid-3 article {
  padding: 1.2rem; background: var(--raised);
  border: 1px solid var(--rule); border-radius: 4px;
}
.grid-3 h3 {
  margin: 0 0 .6rem;
  font-family: var(--font-mono); font-size: .95rem; font-weight: 600; line-height: 1.35;
}
.grid-3 p { margin: 0 0 .7rem; font-size: .95rem; color: var(--ink-soft); }
.more a {
  font-family: var(--font-mono); font-size: .78rem; text-decoration: none;
}

.stats { display: grid; gap: 1.2rem; grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); margin-top: 1.8rem; }
.stat { padding: 1.1rem; border: 1px solid var(--rule); border-radius: 4px; background: var(--raised); }
.stat-n {
  display: block; font-family: var(--font-mono); font-size: 1.7rem; font-weight: 600;
  color: var(--accent); letter-spacing: -.02em; margin-bottom: .4rem;
}
.stat-l { display: block; font-size: .88rem; line-height: 1.5; color: var(--ink-soft); }

.showcase figure.shot { margin: 2rem 0; }

.docs-index .doc-group { margin-top: 2rem; }
.doc-group h2, .doc-group h3 {
  margin: 0 0 .3rem;
  font-family: var(--font-mono); font-size: 1rem; font-weight: 600;
  letter-spacing: .05em; text-transform: uppercase; color: var(--ink);
}
.group-note { margin: 0 0 .9rem; font-size: .92rem; color: var(--ink-faint); }
.card-list {
  list-style: none; margin: 0; padding: 0;
  display: grid; gap: .7rem; grid-template-columns: repeat(auto-fit, minmax(17rem, 1fr));
}
.card-list a {
  display: block; height: 100%; padding: .85rem 1rem;
  background: var(--raised); border: 1px solid var(--rule); border-radius: 4px;
  text-decoration: none; color: var(--ink);
}
.card-list a:hover { border-color: var(--accent-line); background: var(--accent-wash); }
.card-title {
  display: block; font-family: var(--font-mono); font-size: .9rem; font-weight: 600;
  margin-bottom: .3rem;
}
.card-blurb { display: block; font-size: .87rem; line-height: 1.45; color: var(--ink-soft); }

.notfound { padding-top: 6rem; }

/* ── footer ─────────────────────────────────────────────────── */

.foot {
  grid-area: foot;
  border-top: 1px solid var(--rule);
  background: var(--sunken);
  padding: 2rem 1.5rem 2.5rem;
}
.foot-inner { max-width: 62rem; margin: 0 auto; }
.foot-note { margin: 0 0 .7rem; max-width: var(--measure); font-size: .9rem; color: var(--ink-soft); }
.foot-meta {
  margin: 0; font-family: var(--font-mono); font-size: .72rem;
  letter-spacing: .06em; text-transform: uppercase; color: var(--ink-faint);
}
.foot-meta a { color: var(--ink-soft); text-decoration: none; }
.foot-meta a:hover { color: var(--accent); }

/* ── narrow ─────────────────────────────────────────────────── */

@media (max-width: 68rem) {
  body.with-rail { grid-template-columns: var(--rail) minmax(0, 1fr); grid-template-areas: "mast mast" "rail main" "foot foot"; }
  .toc { display: none; }
  main.doc { padding: 2.5rem 2rem 4rem; }
}

@media (max-width: 52rem) {
  .nav-only { display: grid; }
  .top { display: none; }

  /* Each page type has exactly one nav surface, and the button opens whichever
     one that page has. Documentation pages have the rail, which already lists
     everything the top bar does; the landing and 404 pages have no rail, so
     there the top links themselves become the panel. */

  body.landing .top {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; gap: 0;
    margin-left: 0;
    padding: .35rem 1.25rem .9rem;
    background: var(--raised);
    border-bottom: 1px solid var(--rule);
    box-shadow: 0 8px 20px rgb(0 0 0 / 14%);
  }
  body.landing.nav-open .top { display: flex; }
  body.landing .top a { padding: .7rem 0; border-bottom: 1px solid var(--rule-soft); }
  body.landing .top a:last-child { border-bottom: 0; }

  /* The rail gets its own grid row. It previously shared "main" with the
     article, so opening it drew the nav on top of the page content. */
  body.with-rail {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas: "mast" "rail" "main" "foot";
  }
  .rail {
    display: none; grid-area: rail;
    position: static; max-height: none;
    padding: 1.1rem 1.25rem 1.4rem;
    border-right: 0; border-bottom: 1px solid var(--rule);
    background: var(--raised);
  }
  body.nav-open .rail { display: block; }

  main.doc { padding: 2rem 1.25rem 3.5rem; }
  .hero { padding-top: 3rem; }
  .hero-crest { width: 5rem; height: 5rem; }
}

@media print {
  .masthead, .rail, .toc, .foot, .cta, .anchor { display: none; }
  body { background: #fff; color: #000; }
  main.doc { padding: 0; }
}