* { box-sizing: border-box; }
body { margin: 0; background: var(--canvas); color: var(--text); font: 16px/1.6 var(--font-sans); }
a { color: var(--info); text-decoration: none; }
a:hover { text-decoration: underline; }
code, pre { font-family: var(--font-mono); font-size: 14px; }
h1, h2, h3, header.top, nav.side, .badge, .crumbs, figcaption, dl.meta dt, nav.pager small, th, .label { font-family: var(--font-mono); }

header.top { position: sticky; top: 0; z-index: 3; display: flex; flex-wrap: wrap; gap: 6px 18px; align-items: baseline; padding: 11px 22px; background: var(--title); border-bottom: 1px solid var(--bezel-edge); }
header.top .brand { font-weight: 700; color: var(--text); font-size: 16px; letter-spacing: .02em; }
header.top .platform { margin-left: auto; color: var(--muted); font-size: 13px; }
header.top .platform select { margin-left: 6px; font: inherit; color: var(--text); background: var(--panel, transparent); border: 1px solid var(--bezel-edge); border-radius: 4px; padding: 2px 6px; }
header.top .summary { color: var(--muted); font-size: 13px; }

.layout { display: grid; grid-template-columns: 300px minmax(0, 1fr); }
nav.side { position: sticky; top: 47px; align-self: start; height: calc(100vh - 47px); overflow: auto; padding: 18px 14px 40px; background: var(--title); border-right: 1px solid var(--bezel-edge); font-size: 13px; }
.tree, .tree ul { list-style: none; margin: 0; padding: 0; }
.tree ul { padding-left: 14px; border-left: 1px solid var(--bezel-edge); margin-left: 6px; }
.tree li { margin: 1px 0; }
.tree a { display: block; padding: 3px 8px; border-radius: var(--radius-control); color: var(--text); border: 1px solid transparent; }
.tree a:hover { background: var(--control-hover); text-decoration: none; }
.tree a.current { background: var(--ok-fill); color: var(--ok); border-color: var(--ok-dim); font-weight: 700; }
.tree li.root > a { font-weight: 700; }
.tree details > summary { list-style: none; cursor: pointer; display: flex; align-items: center; }
.tree details > summary::-webkit-details-marker { display: none; }
.tree details > summary::before { content: ""; flex: none; width: 0; height: 0; margin: 0 5px 0 3px; border: 4px solid transparent; border-left: 6px solid var(--muted); border-right: 0; transition: transform .15s; }
.tree details[open] > summary::before { transform: rotate(90deg); }
.tree details > summary > a { flex: 1; font-weight: 700; }
.tree li.label { color: var(--muted); font-size: 11px; text-transform: uppercase; letter-spacing: .08em; padding: 10px 8px 2px; }
.tree.extra { margin-top: 18px; padding-top: 12px; border-top: 1px solid var(--bezel-edge); }

main { min-width: 0; max-width: 940px; padding: 26px 44px 60px; }
h1 { font-size: 28px; line-height: 1.25; margin: 6px 0 14px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; letter-spacing: -.01em; }
h2 { font-size: 19px; margin: 36px 0 12px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
h3 { font-size: 15px; margin: 0 0 6px; }
.lede { font-size: 17px; }
.muted { color: var(--muted); }
.crumbs { margin: 0; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.crumbs span { margin: 0 4px; }
blockquote { margin: 0 0 16px; padding: 10px 16px; border-left: 3px solid var(--ok-dim); background: var(--bezel); border-radius: 0 var(--radius-screen) var(--radius-screen) 0; font-style: italic; }

/* Badges are annunciator lamps. */
.badge { display: inline-block; font-size: 11px; font-weight: 700; line-height: 1; padding: 5px 7px; border-radius: var(--radius-control); white-space: nowrap; vertical-align: middle; text-transform: uppercase; letter-spacing: .06em; border: 1px solid; }
.badge.ok { color: var(--ok); background: var(--ok-fill); border-color: var(--ok-dim); }
.badge.bad { color: var(--on-warning); background: var(--warning-fill); border-color: var(--warning); }
.badge.warn { color: var(--caution); background: var(--caution-fill); border-color: var(--caution); }
.badge.idle { color: var(--muted); background: var(--off-fill); border-color: var(--off-edge); }
.tally { display: flex; flex-wrap: wrap; gap: 6px; }

.setup { background: var(--screen); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); padding: 0 18px 10px; margin: 20px 0; overflow: hidden; }
.setup h2 { font-size: 13px; margin: 0 -18px 10px; padding: 7px 18px; gap: 8px; background: var(--title); border-bottom: 1px solid var(--bezel-edge); text-transform: uppercase; letter-spacing: .12em; color: var(--muted); }
.setup h2::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--ok); box-shadow: 0 0 6px var(--ok-dim); }
details.setup { padding: 10px 18px; background: var(--bezel); }
details.setup summary { cursor: pointer; color: var(--muted); }
ol.route li { margin: 4px 0; }
ol.route .kw { color: var(--ok); font-weight: 700; font-family: var(--font-mono); font-size: 14px; }

pre.gherkin { background: var(--screen); color: var(--text); border: 1px solid var(--bezel-edge); border-radius: var(--radius-screen); padding: 12px 16px; overflow-x: auto; line-height: 1.6; margin: 12px 0; }
pre.gherkin .kw { color: var(--ok); font-weight: 700; }

.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 14px; }
.card { display: flex; flex-direction: column; gap: 6px; padding: 14px 16px; background: var(--bezel); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); color: var(--text); }
.card:hover { border-color: var(--ok-dim); text-decoration: none; }
.card > strong { font-family: var(--font-mono); }
.card > span { color: var(--muted); font-size: 14px; }
/* A card's summary is its first lines, not the whole paragraph. */
.card > span, .card.story .body > span { display: -webkit-box; -webkit-box-orient: vertical; -webkit-line-clamp: 4; line-clamp: 4; overflow: hidden; }
.card.story { padding: var(--bezel-pad); gap: 0; }
.card.story img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; display: block; border-radius: var(--radius-screen); background: var(--screen); }
.card.story .body { display: flex; flex-direction: column; gap: 6px; padding: 10px 9px 9px; align-items: flex-start; color: var(--muted); font-size: 14px; }
.card.story .body strong { color: var(--text); font-size: 14px; font-family: var(--font-mono); }

.kicker { margin: 0; font: 700 12px var(--font-mono); color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
ul.before { margin: 6px 0 10px; padding-left: 20px; }
ul.before li, ul.related li { margin: 3px 0; }
dl.topics dt { font-family: var(--font-mono); font-weight: 700; margin-top: 14px; }
dl.topics dd { margin: 2px 0 0; color: var(--muted); }
ul.exps, ul.related { margin: 0; padding-left: 18px; }
ul.exps li { margin: 4px 0; }
dl.glossary dt { font-family: var(--font-mono); font-weight: 700; margin-top: 18px; scroll-margin-top: 60px; }
dl.glossary dd { margin: 4px 0 0; }
dl.glossary dd p { margin: 0 0 8px; }

/* A tutorial's steps, numbered. */
ol.steps { list-style: none; counter-reset: step; padding: 0; margin: 26px 0; }
ol.steps > li { counter-increment: step; position: relative; padding-left: 46px; margin: 0 0 30px; }
ol.steps > li::before { content: counter(step); position: absolute; left: 0; top: 0; display: grid; place-items: center; width: 30px; height: 30px; border-radius: var(--radius-control); background: var(--ok-fill); color: var(--ok); border: 1px solid var(--ok-dim); font: 700 14px var(--font-mono); }
ol.steps p.do { font-size: 17px; font-weight: 600; margin: 2px 0 4px; }
ol.steps p.see { margin: 0 0 8px; }
p.how { font-size: 17px; }
.see-also { color: var(--muted); font-size: 15px; }
details.tested { margin: 14px 0; padding: 8px 16px; background: var(--bezel); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); }
details.tested > summary { cursor: pointer; color: var(--muted); font: 12px var(--font-mono); text-transform: uppercase; letter-spacing: .06em; }
details.tested[open] > summary { margin-bottom: 8px; }

nav.toc { background: var(--bezel); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); padding: 10px 18px; margin: 18px 0; font-size: 15px; }
nav.toc strong { font-family: var(--font-mono); font-size: 12px; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); }
nav.toc ul { margin: 6px 0 0; padding-left: 18px; }

section.exp { border-top: 1px solid var(--bezel-edge); margin-top: 30px; }
section.exp:first-of-type { border-top: 0; }
/* A screenshot is a screen in a bezel: concentric corners. */
figure { margin: 14px 0; max-width: 870px; padding: var(--bezel-pad); background: var(--bezel); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); }
figure img { display: block; width: 100%; aspect-ratio: 16 / 9; object-fit: cover; border-radius: var(--radius-screen); background: var(--screen); }
figcaption { color: var(--muted); font-size: 12px; padding: 7px 4px 2px; }
/* A missing screenshot is a gap to note, not something to look at: keep it small. */
figure.placeholder { max-width: 360px; }
dl.meta { display: grid; grid-template-columns: max-content 1fr; gap: 4px 16px; font-size: 15px; margin: 12px 0 0; }
dl.meta dt { color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: .06em; padding-top: 2px; }
dl.meta dd { margin: 0; }

section.step { margin-top: 28px; }
section.step h2 .n { display: inline-grid; place-items: center; min-width: 28px; height: 28px; padding: 0 6px; border-radius: var(--radius-control); background: var(--ok-fill); color: var(--ok); border: 1px solid var(--ok-dim); font-size: 14px; }
ul.checks { list-style: none; padding: 0; margin: 10px 0; }
ul.checks li { padding: 6px 10px 6px 30px; position: relative; border-radius: var(--radius-control); }
ul.checks li::before { position: absolute; left: 10px; font-weight: 700; font-family: var(--font-mono); }
ul.checks li.ok::before { content: "✓"; color: var(--ok); }
ul.checks li.bad { background: var(--warning-fill); color: var(--on-warning); }
ul.checks li.bad::before { content: "✕"; color: var(--warning); }
ul.checks li.idle::before { content: "○"; color: var(--muted); }
.note { margin: 12px 0; padding: 10px 14px; border-radius: var(--radius-screen); background: var(--bezel); border: 1px solid var(--bezel-edge); border-left: 3px solid var(--caution); }
.note.warn { background: var(--caution-fill); color: var(--caution); border-color: var(--caution); }
.note.bad { background: var(--warning-fill); color: var(--on-warning); border-color: var(--warning); }

/* The DAG is drawn on the tactical map's screen. */
.map { overflow-x: auto; background: var(--map); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); padding: 8px; margin: 10px 0 20px; }
svg.dag { display: block; font: 12px var(--font-mono); }
svg.dag .edge { fill: none; stroke: var(--muted); stroke-width: 1.3; opacity: .7; }
svg.dag .override { fill: none; stroke: var(--caution); stroke-width: 1.5; stroke-dasharray: 5 4; }
svg.dag .conflict { fill: none; stroke: var(--warning); stroke-width: 2; }
svg.dag .head { fill: var(--muted); }
svg.dag .node rect { fill: var(--off-fill); stroke: var(--off-edge); stroke-width: 1.5; }
svg.dag .node text { fill: var(--text); text-anchor: middle; }
svg.dag .node.start rect { fill: var(--screen); stroke: var(--bezel-edge); }
svg.dag .node.v-ok rect { fill: var(--ok-fill); stroke: var(--ok); }
svg.dag .node.v-bad rect { fill: var(--warning-fill); stroke: var(--warning); }
svg.dag .node.v-warn rect { fill: var(--caution-fill); stroke: var(--caution); }
svg.dag .node.invariant rect { stroke-dasharray: 4 3; }
svg.dag .node.unreachable { opacity: .55; }
svg.dag .node.outside { opacity: .5; }
svg.dag .node.outside rect { stroke-dasharray: 2 3; }
svg.dag a:hover rect { stroke-width: 2.5; }

table { border-collapse: separate; border-spacing: 0; width: 100%; font-size: 15px; background: var(--bezel); border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); overflow: hidden; }
th, td { text-align: left; padding: 8px 12px; border-bottom: 1px solid var(--bezel-edge); vertical-align: top; }
tr:last-child td { border-bottom: 0; }
th { color: var(--muted); font-weight: 700; background: var(--title); font-size: 12px; text-transform: uppercase; letter-spacing: .06em; }

nav.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 48px; }
nav.pager a { flex: 1; max-width: 48%; padding: 10px 14px; border: 1px solid var(--bezel-edge); border-radius: var(--radius-panel); background: var(--bezel); }
nav.pager a.next { text-align: right; margin-left: auto; }
nav.pager small { display: block; color: var(--muted); font-size: 11px; text-transform: uppercase; letter-spacing: .06em; }
footer { margin-top: 40px; color: var(--muted); font-size: 13px; }

/* The theme page: swatches, and the components drawn in each variant. */
.swatches { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 8px; margin: 10px 0 24px; }
.swatch { border: 1px solid var(--bezel-edge); border-radius: var(--radius-screen); overflow: hidden; background: var(--bezel); font-family: var(--font-mono); font-size: 12px; }
.swatch .chip { height: 44px; border-bottom: 1px solid var(--bezel-edge); }
.swatch .meta { padding: 6px 8px; display: flex; flex-direction: column; }
.swatch .meta span { color: var(--muted); }
.previews { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: var(--gap); }
.preview { background: var(--canvas); color: var(--text); padding: var(--gap); border-radius: var(--radius-window); border: 1px solid var(--bezel-edge); }
.preview .panel { background: var(--bezel); border-radius: var(--radius-panel); padding: var(--bezel-pad); }
.preview .panel + .panel { margin-top: var(--gap); }
.preview .title { font: 700 11px var(--font-mono); color: var(--muted); text-transform: uppercase; letter-spacing: .08em; padding: 4px 6px 6px; }
.preview .screen { background: var(--screen); border-radius: var(--radius-screen); padding: 10px 12px; font: 13px/1.7 var(--font-mono); }
.preview .row { display: flex; flex-wrap: wrap; gap: 6px; padding: 4px 2px; }
.btn, .lamp { font: 700 12px var(--font-mono); padding: 4px 9px; border-radius: var(--radius-control); border: 1px solid; }
.btn { background: var(--control); color: var(--text); border-color: var(--bezel-edge); }
.btn.active { background: var(--ok-fill); color: var(--ok); border-color: var(--ok-dim); }
.btn.caution { background: var(--caution-fill); color: var(--caution); border-color: var(--caution); }
.btn.danger { background: var(--warning-fill); color: var(--on-warning); border-color: var(--warning); }
.lamp { min-width: 52px; text-align: center; }
.lamp.off { background: var(--off-fill); color: var(--faint); border-color: var(--off-edge); }
.lamp.ok { background: var(--lamp-ok); color: var(--ok); border-color: var(--ok-dim); }
.lamp.caution { background: var(--caution); color: var(--canvas); border-color: var(--caution); }
.lamp.warn { background: var(--lamp-warning); color: var(--on-warning); border-color: var(--warning); }
.ink-ok { color: var(--ok); } .ink-caution { color: var(--caution); } .ink-warning { color: var(--warning); } .ink-info { color: var(--info); } .ink-highlight { color: var(--highlight); } .ink-muted { color: var(--muted); }

@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; }
  nav.side { position: static; height: auto; max-height: 50vh; border-right: 0; border-bottom: 1px solid var(--bezel-edge); }
  main { padding: 18px 16px 40px; }
  h1 { font-size: 23px; }
}