/* Shared shell for the landing sites. Per-site colour comes from the inline
   :root block build.py writes (--accent, --accent-d); per-site character from
   the body class (handbook / industrial / trade / hub).
   No web fonts on purpose: nothing here makes the browser contact a third
   party, and system stacks render instantly. */

:root {
  --bg: #fbfaf7; --surface: #ffffff; --ink: #1b1d21; --muted: #5d636d; --line: #e3e0d8;
  --code: #f1efe9; --shadow: 0 1px 2px rgba(20,20,30,.06), 0 6px 24px rgba(20,20,30,.05);
  --a: var(--accent); --on-a: #fff;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial,
          "Apple SD Gothic Neo", "Malgun Gothic", "Noto Sans KR", sans-serif;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;
  --display: var(--sans);
  --maxw: 1080px; --measure: 70ch; --r: 10px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111317; --surface: #181b21; --ink: #e8e9ec; --muted: #9aa0aa; --line: #2a2e36;
    --code: #1f232a; --shadow: 0 1px 2px rgba(0,0,0,.4); --a: var(--accent-d); --on-a: #121417;
  }
}
:root[data-theme="dark"] {
  --bg: #111317; --surface: #181b21; --ink: #e8e9ec; --muted: #9aa0aa; --line: #2a2e36;
  --code: #1f232a; --shadow: 0 1px 2px rgba(0,0,0,.4); --a: var(--accent-d); --on-a: #121417;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 17px/1.65 var(--sans); }
body.handbook { --display: var(--serif); }
body.industrial { --display: var(--sans); }
body.industrial h1, body.industrial h2 { letter-spacing: -.01em; }
img, svg { max-width: 100%; height: auto; }
a { color: var(--a); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 16px; }
@media (min-width: 720px) { .wrap { padding: 0 28px; } }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; background: var(--surface); padding: 8px 12px; z-index: 10; }
:focus-visible { outline: 2px solid var(--a); outline-offset: 2px; }

/* header */
.top { border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--bg) 88%, transparent);
       position: sticky; top: 0; z-index: 5; backdrop-filter: blur(8px); }
.bar { display: flex; align-items: center; gap: 16px; min-height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none;
         font: 700 18px/1 var(--display); letter-spacing: -.01em; margin-right: auto; }
.brand svg { width: 28px; height: 28px; flex: none; }
.brand svg .fg { fill: var(--on-a); } .brand svg .fgs { stroke: var(--on-a); }
.brand b { color: var(--a); font-weight: inherit; }
.nav { display: flex; gap: 4px; align-items: center; flex-wrap: wrap; }
.nav a { color: var(--muted); text-decoration: none; padding: 6px 10px; border-radius: 6px; font-size: 15px; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); background: var(--code); }
.langsw { display: inline-flex; margin-left: 8px; border: 1px solid var(--line); border-radius: 6px; overflow: hidden; }
.langsw a { border-radius: 0; font-size: 13px; padding: 4px 9px; }
.langsw a[aria-current="true"] { background: var(--a); color: var(--on-a); }
.navtoggle { display: none; background: none; border: 0; padding: 8px; cursor: pointer; }
.navtoggle span { display: block; width: 20px; height: 2px; background: var(--ink); margin: 4px 0; }
@media (max-width: 820px) {
  .navtoggle { display: block; }
  .nav { display: none; position: absolute; left: 0; right: 0; top: 60px; background: var(--bg);
         border-bottom: 1px solid var(--line); flex-direction: column; align-items: stretch; padding: 8px 16px 16px; }
  .nav.open { display: flex; }
  .langsw { margin: 8px 0 0; align-self: flex-start; }
}

/* type */
main { padding-bottom: 56px; }
h1, h2, h3 { font-family: var(--display); line-height: 1.2; text-wrap: balance; }
h1 { font-size: clamp(30px, 5vw, 46px); margin: 0 0 16px; letter-spacing: -.02em; }
h2 { font-size: clamp(22px, 3vw, 28px); margin: 48px 0 12px; }
h3 { font-size: 19px; margin: 28px 0 8px; }
p, ul, ol, table, .callout, details { max-width: var(--measure); }
.lede { font-size: clamp(18px, 2.4vw, 20px); color: var(--muted); max-width: 62ch; }
.kicker { font: 600 13px/1 var(--mono); letter-spacing: .08em; text-transform: uppercase; color: var(--a); margin: 0 0 14px; }
code { font-family: var(--mono); font-size: .88em; background: var(--code); padding: 1px 5px; border-radius: 4px; }
.crumb { font-size: 14px; color: var(--muted); padding-top: 22px; }
.crumb a { color: var(--muted); }
.updated { color: var(--muted); font-size: 14px; margin-top: 40px; }
article, .prose { max-width: var(--measure); }

.hero { padding: 48px 0 16px; }
.is-home .hero { padding: 64px 0 24px; }
.hero .lede { margin-bottom: 0; }

/* blocks */
.cards { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(min(100%, 400px), 1fr)); margin: 20px 0; max-width: none; }
.card { display: block; background: var(--surface); border: 1px solid var(--line); border-radius: var(--r);
        padding: 18px 20px; text-decoration: none; color: var(--ink); box-shadow: var(--shadow); }
a.card:hover { border-color: var(--a); }
.card h3 { margin: 0 0 6px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.card .go { display: inline-block; margin-top: 10px; color: var(--a); font-size: 14px; font-weight: 600; }

.callout { border-left: 3px solid var(--a); background: var(--surface); padding: 14px 18px; border-radius: 0 var(--r) var(--r) 0; margin: 22px 0; }
.callout p { margin: 0; }
.callout p + p { margin-top: 8px; }

.table-wrap { overflow-x: auto; margin: 18px 0; max-width: 100%; }
table { border-collapse: collapse; width: 100%; font-size: 15px; background: var(--surface); max-width: none; }
th, td { text-align: left; vertical-align: top; padding: 10px 12px; border-bottom: 1px solid var(--line); }
th { font-weight: 600; background: var(--code); }
.table-wrap table { min-width: 560px; }

ul.check { list-style: none; padding: 0; }
ul.check li { position: relative; padding-left: 30px; margin: 8px 0; }
ul.check li::before { content: ""; position: absolute; left: 2px; top: 6px; width: 16px; height: 16px;
                      border: 2px solid var(--a); border-radius: 3px; }
ol.steps { counter-reset: s; list-style: none; padding: 0; }
ol.steps > li { counter-increment: s; position: relative; padding-left: 44px; margin: 16px 0; }
ol.steps > li::before { content: counter(s); position: absolute; left: 0; top: 0; width: 30px; height: 30px;
                        border-radius: 50%; background: var(--a); color: var(--on-a); font: 600 14px/30px var(--mono); text-align: center; }
details { border: 1px solid var(--line); border-radius: var(--r); padding: 10px 16px; margin: 10px 0; background: var(--surface); }
summary { cursor: pointer; font-weight: 600; }
details p { margin: 8px 0 4px; }

figure { margin: 24px 0; max-width: var(--measure); }
figcaption { color: var(--muted); font-size: 14px; margin-top: 8px; }
.diagram { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r); padding: 16px; }
.diagram text { font-family: var(--sans); fill: var(--ink); }
.diagram .dim { fill: var(--muted); }
.diagram .ln { stroke: var(--ink); }
.diagram .acc { stroke: var(--a); }
.diagram .accf { fill: var(--a); }
.diagram .box { fill: var(--code); stroke: var(--line); }

.two { display: grid; gap: 28px; grid-template-columns: 1fr; }
@media (min-width: 900px) { .two { grid-template-columns: 1.4fr 1fr; align-items: start; } }

.btn { display: inline-block; background: var(--a); color: var(--on-a); text-decoration: none; font-weight: 600;
       padding: 10px 18px; border-radius: 8px; white-space: nowrap; }
.btn:hover { filter: brightness(1.08); }
.cta { display: flex; flex-wrap: wrap; gap: 16px; align-items: center; justify-content: space-between;
       margin: 56px 0 0; padding: 22px 24px; border: 1px solid var(--line); border-radius: var(--r); background: var(--surface); }
.cta-k { margin: 0; font: 600 12px/1.2 var(--mono); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.cta-t { margin: 4px 0 0; font-size: 17px; max-width: 58ch; }

/* footer */
.foot { border-top: 1px solid var(--line); padding: 32px 0 40px; font-size: 14px; color: var(--muted); }
.fgrid { display: grid; gap: 20px; grid-template-columns: 1fr; }
@media (min-width: 720px) { .fgrid { grid-template-columns: 1.3fr 1fr; } }
.fname { font: 700 16px/1.2 var(--display); color: var(--ink); margin: 0 0 6px; }
.fabout p { margin: 0 0 6px; }
.flinks { display: flex; flex-wrap: wrap; gap: 6px 16px; align-content: start; }
.flinks a, .legal a { color: var(--muted); }
.disclose { border-top: 1px solid var(--line); padding-top: 16px; margin-top: 20px; max-width: 90ch; }
.legal { margin: 8px 0 0; }

@media print { .top, .cta, .foot, .navtoggle { display: none; } body { background: #fff; } }

/* glossary */
dl.glossary { max-width: var(--measure); }
dl.glossary dt { font-weight: 700; margin-top: 22px; scroll-margin-top: 80px; }
dl.glossary dd { margin: 4px 0 0; color: var(--ink); }
body.trade h1 { letter-spacing: -.015em; }

/* Korean: break between words, not inside them; no tracking on Hangul labels */
:lang(ko) { word-break: keep-all; overflow-wrap: anywhere; }
:lang(ko) .kicker, :lang(ko) .cta-k { letter-spacing: .02em; }

/* wide diagrams scroll sideways on phones instead of shrinking past legibility */
.diagram.wide { overflow-x: auto; }
.diagram.wide svg { min-width: 600px; }