/* control-plane — the look of a precise instrument at night: a near-black ground tinted toward the accent, one accent
   used only for what is live (the next move, a held gate, a line being written), a grotesk for what is said and a mono
   for everything the machine says (states, files, commands, sources). Thin rules, 4px corners, panels of smoked glass.
   Colours and fonts come only from the theme variables (site.json: theme). */
:root {
  --g: clamp(18px, 3.2vw, 56px); --nav: 68px; --ease: cubic-bezier(.2, .7, .2, 1); --ease-s: cubic-bezier(.65, 0, .35, 1);
  /* four tiers of ink; the quietest (small mono: sources, keys, counts) still clears WCAG AA on the panels (≥ 4.5:1) */
  --tx: var(--fg); --tx2: color-mix(in srgb, var(--fg) 78%, transparent); --tx3: color-mix(in srgb, var(--fg) 68%, transparent); --tx4: color-mix(in srgb, var(--fg) 62%, transparent);
  --ln: color-mix(in srgb, var(--fg) 9%, transparent); --ln2: color-mix(in srgb, var(--fg) 16%, transparent); --ln3: color-mix(in srgb, var(--fg) 28%, transparent);
  --panel: color-mix(in srgb, var(--bg) 78%, transparent); --panel2: color-mix(in srgb, var(--bg) 90%, transparent);
  --hi: inset 0 1px 0 color-mix(in srgb, var(--fg) 7%, transparent);
  --r: 4px; --r2: 8px;
  --s0: 11px; --s1: clamp(14px, .95vw, 15.5px); --s2: clamp(15px, 1.12vw, 17.5px); --s3: clamp(22px, 1.9vw, 30px);
  --s4: clamp(30px, 3.1vw, 48px); --s5: clamp(40px, 4.6vw, 74px);
  color-scheme: dark;
}
html { background: var(--bg); color: var(--tx); font-family: var(--font-sans); -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
body { margin: 0; background: transparent; }
a { color: inherit; }
::selection { background: var(--accent); color: var(--bg); }
button, input { font: inherit; color: inherit; }
html.is-settling *, html.is-settling *::before, html.is-settling *::after { transition: none !important; }
code, pre, .mono-k, .label, .kicker, .btn, .nav a, .sound, .facts, .stats .mono-k, .rail, .st-k, .src, .sc-foot, .files, .snap dt, .ranked, .chip, .dl-list, .ask-line, .hint, .loader, .foot .mono-k, .ft-bot, .tip, .tag { font-family: var(--font-mono); }
.mono-k { font-size: var(--s0); font-weight: 500; letter-spacing: .14em; text-transform: uppercase; color: var(--tx3); }
.dim { color: var(--tx3); }
a:focus-visible, button:focus-visible, input:focus-visible { outline: 1px solid var(--accent); outline-offset: 3px; }

/* ---------- loader: the command the session opens with, real progress ---------- */
.loader { background: var(--bg); display: grid; place-items: center; }
.loader-in { width: min(440px, 82vw); display: grid; gap: 14px; }
.ld-cmd { margin: 0; font-size: 15px; color: var(--tx); display: flex; align-items: center; gap: 10px; }
.ld-p { color: var(--accent); }
.ld-caret { width: 8px; height: 15px; background: var(--accent); animation: caret 1s steps(1) infinite; }
@keyframes caret { 50% { opacity: 0; } }
.ld-l { margin: 0; display: flex; justify-content: space-between; font-size: var(--s0); letter-spacing: .14em; text-transform: uppercase; color: var(--tx3); }
.ld-l b { color: var(--tx); font-weight: 500; font-variant-numeric: tabular-nums; }
.ld-line { position: relative; height: 1px; background: var(--ln2); overflow: hidden; }
.loader-bar { position: absolute; inset: 0; background: var(--accent); transform-origin: 0 50%; transform: scaleX(var(--p, 0)); box-shadow: 0 0 12px var(--accent); }
.ld-m { margin: 0; font-size: var(--s0); letter-spacing: .12em; text-transform: uppercase; color: var(--tx4); }
.reduced .ld-caret { animation: none; }

/* ---------- header ---------- */
.top { position: fixed; z-index: 30; top: 0; left: 0; right: 0; height: var(--nav); display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 28px; padding: 0 var(--g); }
.top::before { content: ''; position: absolute; inset: 0; z-index: -1; pointer-events: none; background: color-mix(in srgb, var(--bg) 72%, transparent); border-bottom: 1px solid var(--ln); backdrop-filter: blur(14px) saturate(1.2); -webkit-backdrop-filter: blur(14px) saturate(1.2); }
.brand { display: flex; align-items: center; text-decoration: none; }
.brand img { height: 26px; width: auto; display: block; }
.nav { display: flex; justify-content: center; gap: 4px; }
.nav a { position: relative; padding: 10px 12px; font-size: var(--s0); font-weight: 500; letter-spacing: .14em; text-transform: uppercase; text-decoration: none; color: var(--tx3); transition: color .3s; white-space: nowrap; }
.nav a:hover, .nav a:focus-visible, .nav a[aria-current] { color: var(--tx); }
.nav a[aria-current]::after { content: ''; position: absolute; left: 12px; right: 12px; bottom: 4px; height: 1px; background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.top-r { display: flex; gap: 10px; align-items: center; }
.sound { display: inline-flex; align-items: center; gap: 9px; height: 36px; padding: 0 12px; border-radius: var(--r); background: transparent; border: 1px solid var(--ln2); font-size: var(--s0); letter-spacing: .14em; text-transform: uppercase; color: var(--tx2); cursor: pointer; transition: border-color .3s, color .3s; }
.sound:hover, .sound.is-on { border-color: var(--accent); color: var(--tx); }
/* phones: the chapters behind a Menu button (hidden on wide screens, where the nav is in the header) */
.menu-btn { display: none; align-items: center; gap: 9px; height: 34px; padding: 0 11px; border-radius: var(--r); background: transparent; border: 1px solid var(--ln2); font-family: var(--font-mono); font-size: var(--s0); letter-spacing: .14em; text-transform: uppercase; color: var(--tx2); cursor: pointer; }
.menu-i { display: grid; gap: 4px; width: 12px; } .menu-i i { height: 1px; background: currentColor; transition: transform .3s var(--ease); }
.menu-btn[aria-expanded="true"] { border-color: var(--accent); color: var(--tx); }
.menu-btn[aria-expanded="true"] .menu-i i:first-child { transform: translateY(2.5px) rotate(45deg); } .menu-btn[aria-expanded="true"] .menu-i i:last-child { transform: translateY(-2.5px) rotate(-45deg); }

/* ---------- buttons ---------- */
.btn { display: inline-flex; align-items: center; gap: 12px; height: 44px; padding: 0 18px; border-radius: var(--r); font-size: 12px; font-weight: 500; letter-spacing: .12em; text-transform: uppercase; text-decoration: none;
  border: 1px solid var(--ln2); background: color-mix(in srgb, var(--bg) 70%, transparent); color: var(--tx); transition: border-color .3s, background .3s, box-shadow .3s, transform .3s var(--ease); white-space: nowrap; }
.btn:hover { border-color: var(--ln3); background: color-mix(in srgb, var(--fg) 6%, var(--bg)); }
.btn i { font-style: normal; transition: transform .3s var(--ease); }
.btn:hover i { transform: translateX(3px); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: color-mix(in srgb, var(--bg) 88%, #000); box-shadow: 0 0 0 1px color-mix(in srgb, var(--accent) 25%, transparent), 0 10px 34px color-mix(in srgb, var(--accent) 14%, transparent); }
.btn-primary:hover { background: color-mix(in srgb, var(--accent) 88%, var(--fg)); border-color: var(--accent); }
.btn-s { height: 36px; padding: 0 14px; }
.link-btn { background: none; border: 0; padding: 6px 0; font-family: var(--font-mono); font-size: 12px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx2); text-decoration: underline; text-decoration-color: var(--ln3); text-underline-offset: 5px; cursor: pointer; }
.link-btn:hover { color: var(--tx); text-decoration-color: var(--accent); }

/* ---------- chapters ---------- */
main { position: relative; z-index: 2; overflow-x: clip; }
.ch { position: relative; min-height: var(--h, 120vh); padding: calc(var(--nav) + 9vh) var(--g) 10vh; box-sizing: border-box; }
.label { display: flex; gap: 14px; align-items: center; margin: 0 0 20px; font-size: var(--s0); font-weight: 500; letter-spacing: .16em; text-transform: uppercase; color: var(--tx3); }
.label::before { content: ''; width: 28px; height: 1px; background: var(--ln3); }
.label-n { color: var(--tx); }
.ch-title { font: 500 var(--s4)/1.06 var(--font-display); letter-spacing: -.028em; margin: 0 0 20px; text-wrap: balance; max-width: 16em; }
.body { max-width: 34em; font-size: var(--s2); line-height: 1.55; color: var(--tx2); }
.body p { margin: 0 0 12px; }
.src { margin: 12px 0 0; font-size: 10.5px; letter-spacing: .06em; color: var(--tx4); line-height: 1.5; }
.panel, .sess-card, .con-card, .dials, .finder, .harness, .card { background: var(--panel); border: 1px solid var(--ln2); border-radius: var(--r2); box-shadow: var(--hi), 0 30px 80px -40px rgba(0, 0, 0, .9);
  backdrop-filter: blur(16px) saturate(1.15); -webkit-backdrop-filter: blur(16px) saturate(1.15); }

/* ---------- hero ---------- */
.ch-hero { display: flex; flex-direction: column; justify-content: center; padding-top: calc(var(--nav) + 4vh); padding-bottom: 150px; }
/* a soft shade behind the words: the world stays whole, the copy stays crisp (tall enough to hold the harness list under
   the buttons on a large screen, where the lit plane reaches the words' row) */
.ch-hero::before, .ch-install::before { content: ''; position: absolute; inset: 0 auto 0 0; width: min(62vw, 980px); z-index: -1; pointer-events: none;
  background: radial-gradient(125% 90% at 0% 50%, color-mix(in srgb, var(--bg) 78%, transparent) 0%, color-mix(in srgb, var(--bg) 56%, transparent) 48%, transparent 80%); }
/* the closing chapter's words are long and the lit gate stands beside them: a deeper shade */
.ch-install::before { width: min(66vw, 1040px); background: radial-gradient(130% 100% at 0% 62%, color-mix(in srgb, var(--bg) 84%, transparent) 0%, color-mix(in srgb, var(--bg) 64%, transparent) 48%, transparent 80%);
  -webkit-mask-image: linear-gradient(to bottom, transparent 0, #000 24vh); mask-image: linear-gradient(to bottom, transparent 0, #000 24vh); }   /* the shade fades in: no straight edge where the chapter starts */
.ch-hero > *, .ch-install > * { position: relative; }
.ch-constraint::before, .ch-plane::before, .ch-phase0::before, .ch-system::before { content: ''; position: absolute; inset: 0 auto 0 0; width: min(58vw, 900px); z-index: -1; pointer-events: none;
  background: linear-gradient(90deg, color-mix(in srgb, var(--bg) 84%, transparent) 0%, color-mix(in srgb, var(--bg) 62%, transparent) 55%, transparent 100%); }
.hero-in { max-width: min(640px, 48vw); }
.kicker { display: inline-flex; align-items: center; gap: 12px; margin: 0 0 26px; font-size: var(--s0); font-weight: 500; letter-spacing: .16em; text-transform: uppercase; color: var(--tx2); }
.kicker i { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); animation: pulse 2.4s ease-in-out infinite; }
@keyframes pulse { 50% { opacity: .35; } }
.reduced .kicker i { animation: none; }
.hero-title { font: 500 var(--s5)/1.0 var(--font-display); letter-spacing: -.035em; margin: 0 0 26px; text-wrap: balance; }
.hero-title .hl { display: block; }
.hero-title .is-accent { color: var(--accent); }
.hero-sub { max-width: 31em; font-size: var(--s2); line-height: 1.55; color: var(--tx2); margin: 0 0 30px; }
.ctas { display: flex; flex-wrap: wrap; gap: 12px; margin: 0 0 34px; }
.works { display: grid; gap: 10px; margin: 0 0 16px; }
.works .mono-k { margin: 0; }
.works ul { display: flex; flex-wrap: wrap; gap: 6px 18px; list-style: none; margin: 0; padding: 0; font-size: 13.5px; color: var(--tx2); }
.works-note { margin: 0; font-size: 13.5px; color: var(--tx3); }
.facts { display: flex; flex-wrap: wrap; gap: 8px 22px; margin: 0; font-size: var(--s0); letter-spacing: .14em; text-transform: uppercase; color: var(--tx2); }
.facts span::before { content: ''; display: inline-block; width: 4px; height: 4px; margin-right: 10px; vertical-align: 2px; background: var(--ln3); }
.stats { position: absolute; left: var(--g); right: var(--g); bottom: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--ln2); }
/* the facts row leaves the hero over the lit plane: a shade under it, strongest behind the words */
.stats::before { content: ''; position: absolute; z-index: -1; pointer-events: none; left: calc(-1 * var(--g)); right: calc(-1 * var(--g)); top: -40px; bottom: 0;
  background: linear-gradient(to bottom, transparent, color-mix(in srgb, var(--bg) 74%, transparent) 40px, color-mix(in srgb, var(--bg) 82%, transparent)); }
.stats li { display: grid; gap: 6px; align-content: start; padding: 18px 22px 22px 0; }
.stats li + li { padding-left: 22px; border-left: 1px solid var(--ln); }
.stats b { font: 500 var(--s3)/1.1 var(--font-display); letter-spacing: -.02em; }
.stat-t { font-size: 13px; line-height: 1.45; color: var(--tx3); max-width: 24em; }
.hint { position: absolute; right: var(--g); bottom: 160px; display: flex; align-items: center; gap: 12px; margin: 0; padding: 9px 16px 9px 14px; font-size: var(--s0); letter-spacing: .14em; text-transform: uppercase; color: var(--tx2);
  /* it points at the lit pins, so it sits over them: a backing of its own keeps it readable there */
  background: var(--panel2); border: 1px solid var(--ln2); border-radius: 999px; backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); }
.hint i { width: 34px; height: 1px; background: var(--ln3); }
.no-hover .hint { display: none; }

/* ---------- the session: a sticky card that steps through six states of the world ---------- */
.sess-head { position: relative; max-width: 760px; margin-bottom: 7vh; }
/* the intro reads over the plane: a shade behind it from the left edge, soft at the top and bottom (the pool of light
   sits to the right of the words: the session's first key moves it there) */
.ch-session .sess-head::before { content: ''; position: absolute; z-index: -1; pointer-events: none; left: calc(-1 * var(--g)); top: -9vh; bottom: -6vh; width: min(68vw, 1060px);
  background: linear-gradient(90deg, color-mix(in srgb, var(--bg) 80%, transparent) 0%, color-mix(in srgb, var(--bg) 56%, transparent) 58%, transparent 100%);
  -webkit-mask-image: linear-gradient(to bottom, transparent, #000 22%, #000 80%, transparent); mask-image: linear-gradient(to bottom, transparent, #000 22%, #000 80%, transparent); }
.sess { position: relative; }
.sess-card { position: relative; width: min(590px, 44vw); overflow: hidden; }
.sc-top { display: flex; align-items: center; gap: 14px; padding: 12px 18px; border-bottom: 1px solid var(--ln); }
.dots { display: flex; gap: 6px; } .dots i { width: 7px; height: 7px; border-radius: 50%; border: 1px solid var(--ln3); }
.sc-src { margin-left: auto; color: var(--accent); }
.rail { display: grid; grid-template-columns: repeat(6, 1fr); margin: 0; padding: 14px 10px 12px; list-style: none; border-bottom: 1px solid var(--ln); position: relative; }
.rail::before { content: ''; position: absolute; left: calc(100% / 12); right: calc(100% / 12); top: 30px; height: 1px; background: var(--ln2); }
.rail::after { content: ''; position: absolute; left: calc(100% / 12); top: 30px; height: 1px; width: calc((100% - 100% / 6) * var(--rp, 0)); background: var(--accent); box-shadow: 0 0 8px var(--accent); transition: width .6s var(--ease); }
.rail a { position: relative; z-index: 1; display: grid; justify-items: center; gap: 8px; text-decoration: none; color: var(--tx3); }
.rd-n { width: 30px; height: 30px; display: grid; place-items: center; border-radius: 50%; border: 1px solid var(--ln3); background: var(--panel2); font-size: 10.5px; transition: background .4s, color .4s, border-color .4s, box-shadow .4s; }
.rd-l { font-size: 10px; letter-spacing: .14em; text-transform: uppercase; }
.rail li.is-done .rd-n { border-color: var(--accent); color: var(--accent); }
.rail li.is-on .rd-n { background: var(--accent); border-color: var(--accent); color: var(--bg); box-shadow: 0 0 18px color-mix(in srgb, var(--accent) 45%, transparent); }
.rail li.is-on .rd-l { color: var(--tx); }
.sc-body { position: relative; padding: 20px 22px 18px; }
.step + .step { margin-top: 42px; padding-top: 42px; border-top: 1px solid var(--ln); }
.st-k { margin: 0 0 10px; font-size: 10.5px; letter-spacing: .14em; text-transform: uppercase; color: var(--tx4); }
/* phones: each step is its own screen, so each one says again whose data it is (the card's top line scrolls away) */
.st-ex { display: none; margin: -4px 0 10px; font-family: var(--font-mono); font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: var(--tx3); }
.st-t { margin: 0 0 8px; font: 500 var(--s3)/1.15 var(--font-display); letter-spacing: -.02em; }
.st-p { margin: 0 0 16px; font-size: 14.5px; line-height: 1.55; color: var(--tx2); max-width: 36em; }
.sc-foot { display: flex; align-items: center; gap: 16px; padding: 0 0 0 18px; border-top: 1px solid var(--ln); height: 50px; }
.sc-count { font-size: 11px; color: var(--tx3); } .sc-count b { color: var(--tx); font-weight: 500; }
.sc-next { margin-left: auto; height: 100%; display: flex; align-items: center; gap: 12px; padding: 0 18px; border-left: 1px solid var(--ln); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; text-decoration: none; color: var(--accent); }
.sc-next i { font-style: normal; }
.sess-track { display: none; }
/* live (desktop): the card sticks and shows one step; the track below gives each step a screen of scroll */
/* the sticky card never runs past the screen: it is capped to what is left under its top; its body gives way (the ledger
   scrolls inside first; the body only scrolls if a step still does not fit) */
html.cp-live .sess-card { --card-top: calc(var(--nav) + 3.5vh); position: sticky; top: var(--card-top); max-height: calc(100vh - var(--card-top) - 12px); display: flex; flex-direction: column; }
html.cp-live .sess-card > .sc-body { flex: 1 1 auto; min-height: 0; overflow: auto; overscroll-behavior: contain; scrollbar-width: thin; }
html.cp-live .sess-card > .sc-top, html.cp-live .sess-card > .rail, html.cp-live .sess-card > .sc-foot { flex: none; }
html.cp-live .sess-track { display: block; margin-top: calc(-1 * var(--card-h, 600px)); }
html.cp-live .st-stop { height: 100vh; }
html.cp-live .st-stop:last-child { height: 115vh; }
html.cp-live .sc-body { display: grid; }
html.cp-live .step { grid-area: 1 / 1; margin: 0; padding: 0; border: 0; opacity: 0; visibility: hidden; transform: translate3d(0, 10px, 0); transition: opacity .45s var(--ease), transform .6s var(--ease), visibility 0s .45s; }
html.cp-live .step.is-on { opacity: 1; visibility: visible; transform: none; transition: opacity .55s var(--ease) .12s, transform .7s var(--ease) .12s, visibility 0s; }

/* step widgets */
.wg { font-size: 13px; }
.files { list-style: none; margin: 0 0 14px; padding: 0; border: 1px solid var(--ln); border-radius: var(--r); }
.files li { display: grid; grid-template-columns: 1.1fr 1fr auto; gap: 12px; align-items: center; padding: 7px 12px; font-size: 12px; }
.files li + li { border-top: 1px solid var(--ln); }
.f-n { color: var(--tx); } .f-r { color: var(--tx3); font-size: 11px; letter-spacing: .06em; text-transform: uppercase; }
.f-s { font-size: 10px; letter-spacing: .14em; text-transform: uppercase; color: var(--tx4); transition: color .4s; }
.files li.is-read .f-s { color: var(--accent); }
.files li.is-read .f-s::before { content: '✓ '; }
.snap { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 18px; margin: 0; }
.snap div { display: grid; gap: 3px; } .snap dt { font-size: 10px; letter-spacing: .14em; text-transform: uppercase; color: var(--tx4); } .snap dd { margin: 0; font-size: 13.5px; color: var(--tx); line-height: 1.35; }
.bc { display: grid; gap: 4px; padding: 12px 14px; margin: 0 0 12px; border: 1px solid var(--ln); border-left: 2px solid var(--accent); border-radius: var(--r); }
.bc .mono-k { margin: 0; } .bc-v { margin: 0; font: 500 22px/1.15 var(--font-display); letter-spacing: -.015em; } .bc-win { margin: 0; font-size: 12.5px; color: var(--tx2); }
.ranked { list-style: none; margin: 0; padding: 0; border: 1px solid var(--ln); border-radius: var(--r); }
.ranked li { display: grid; grid-template-columns: 30px 1fr 132px; gap: 10px; align-items: center; padding: 8px 12px; transition: background .4s; }
.ranked li + li { border-top: 1px solid var(--ln); }
.ranked li.is-top { background: color-mix(in srgb, var(--accent) 7%, transparent); }
.rk-n { font-size: 11px; color: var(--tx4); } .ranked li.is-top .rk-n { color: var(--accent); }
.rk-t { display: grid; gap: 2px; min-width: 0; } .rk-t b { font: 500 13.5px/1.3 var(--font-sans); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; } .rk-d { font-size: 9.5px; letter-spacing: .14em; text-transform: uppercase; color: var(--tx4); }
.rk-s { display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: center; }
.bar { height: 3px; background: var(--ln); position: relative; overflow: hidden; border-radius: 2px; }
.bar i { position: absolute; inset: 0 auto 0 0; width: var(--w); background: var(--tx3); transition: width .8s var(--ease); }
.ranked li.is-top .bar i { background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.rk-v { font-size: 11.5px; color: var(--tx2); font-variant-numeric: tabular-nums; }
.ranked.is-small li { padding: 6px 10px; } .ranked.is-small .rk-t b { font-size: 12.5px; }
.mk-h { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin: 0 0 10px; font-size: 12px; }
.mk-h code { color: var(--tx2); }
.draft { max-height: 300px; overflow: hidden; padding: 12px 14px; border: 1px solid var(--ln); border-radius: var(--r); background: color-mix(in srgb, var(--bg) 50%, transparent); font-family: var(--font-mono); font-size: 11.5px; line-height: 1.55; color: var(--tx2); }
.draft .dl { margin: 0; position: relative; }
.draft .dl.is-h { color: var(--tx); margin-top: 6px; }
.draft .dl-b { display: none; }
.draft .dl.is-flag { color: var(--tx); }
[data-review="flag"] .draft .dl.is-flag, .wg-review .draft .dl.is-flag { background: color-mix(in srgb, var(--accent) 10%, transparent); box-shadow: -8px 0 0 -6px var(--accent); }
[data-review="fixed"] .draft .dl.is-flag .dl-a { display: none; } [data-review="fixed"] .draft .dl.is-flag .dl-b { display: inline; }
.personas { list-style: none; margin: 0 0 12px; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 6px; }
.personas li { display: grid; grid-template-columns: 30px 1fr; grid-template-rows: auto auto; column-gap: 10px; padding: 8px 10px; border: 1px solid var(--ln); border-radius: var(--r); transition: border-color .4s, background .4s; }
.pi { grid-row: span 2; width: 30px; height: 30px; display: grid; place-items: center; border-radius: 50%; border: 1px solid var(--ln3); font-family: var(--font-mono); font-size: 10.5px; }
.pn { font-size: 12.5px; } .ps { font-family: var(--font-mono); font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx4); }
[data-review="flag"] .personas li[data-raises], [data-review="flag"] .personas li[data-agrees] { border-color: color-mix(in srgb, var(--accent) 60%, transparent); }
[data-review="flag"] .personas li[data-raises] .pi { border-color: var(--accent); color: var(--accent); }
.finding { padding: 12px 14px; border: 1px solid var(--ln); border-left: 2px solid var(--accent); border-radius: var(--r); display: grid; gap: 6px; }
.finding p { margin: 0; font-size: 13px; line-height: 1.45; color: var(--tx2); }
.fd-h { display: flex; gap: 10px; flex-wrap: wrap; align-items: baseline; font-family: var(--font-mono); font-size: 10.5px !important; letter-spacing: .12em; text-transform: uppercase; }
.sev { color: var(--accent); } .fd-t { color: var(--tx) !important; font-size: 14px !important; }
.fd-ok { font-family: var(--font-mono); font-size: 11px !important; letter-spacing: .12em; text-transform: uppercase; color: var(--tx4) !important; }
[data-review="fixed"] .fd-ok { color: var(--accent) !important; } [data-review="fixed"] .fd-ok::before { content: '✓ '; }
.g-dial { margin: 0 0 8px; font-size: 13px; } .g-dial b { font-weight: 500; color: var(--accent); }
.g-why { margin: 0 0 10px; font-size: 13.5px; line-height: 1.5; color: var(--tx2); }
.g-code { margin: 0 0 14px; padding: 9px 12px; border: 1px solid var(--ln); border-radius: var(--r); background: color-mix(in srgb, var(--bg) 60%, transparent); font-size: 11px; line-height: 1.5; color: var(--tx2); white-space: pre-wrap; word-break: break-all; }
.hold { display: flex; align-items: center; gap: 22px; flex-wrap: wrap; }
.hold-btn { --hold: 0; position: relative; display: inline-flex; align-items: center; gap: 14px; height: 56px; padding: 0 22px 0 8px; border-radius: 999px; border: 1px solid var(--accent); background: color-mix(in srgb, var(--accent) calc(8% + var(--hold) * 30%), var(--bg)); color: var(--tx);
  font-family: var(--font-mono); font-size: 12px; font-weight: 500; letter-spacing: .14em; text-transform: uppercase; cursor: pointer; user-select: none; -webkit-user-select: none; touch-action: none;
  box-shadow: 0 0 calc(var(--hold) * 40px) color-mix(in srgb, var(--accent) calc(var(--hold) * 60%), transparent); transition: background .2s; }
.hold-btn svg { width: 42px; height: 42px; transform: rotate(-90deg); }
.ring-bg { fill: none; stroke: var(--ln3); stroke-width: 1.5; }
.ring { fill: none; stroke: var(--accent); stroke-width: 2.5; stroke-dasharray: 100; stroke-dashoffset: calc(100 - var(--hold) * 100); }
[data-state="declined"] .hold-btn { border-color: var(--ln3); }
/* the label stays light on a fill that stays dark while held (≥ 6.8:1 at any point of the hold); a yes turns it to the accent */
[data-state="approved"] .hold-btn { background: var(--accent); border-color: var(--accent); color: var(--bg); }
[data-state="approved"] .hold-btn .ring-bg { stroke: color-mix(in srgb, var(--bg) 35%, transparent); } [data-state="approved"] .hold-btn .ring { stroke: var(--bg); }
.hold-help { margin: 10px 0 0; font-size: 11.5px; color: var(--tx4); }
.g-out { margin: 12px 0 0; font-family: var(--font-mono); font-size: 12px; letter-spacing: .06em; color: var(--tx2); min-height: 1.5em; }
[data-state="approved"] .g-out { color: var(--accent); }
.c-wait { margin: 0 0 12px; padding: 10px 12px; border: 1px dashed var(--ln3); border-radius: var(--r); font-size: 13px; line-height: 1.5; color: var(--tx2); }
[data-state="approved"] .c-wait, [data-state="declined"] .c-wait { display: none; }
.ledger { border: 1px solid var(--ln); border-radius: var(--r); padding: 10px 12px; margin: 0 0 12px; background: color-mix(in srgb, var(--bg) 60%, transparent); }
.lg-h { display: flex; justify-content: space-between; align-items: center; margin: 0 0 8px; font-size: 12px; }
.lines { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; max-height: 190px; overflow: auto; }
.ll code { display: block; font-size: 10.5px; line-height: 1.5; color: var(--tx3); word-break: break-all; }
.ll.is-new code { color: var(--tx); }
.ll.is-new { position: relative; padding-left: 10px; } .ll.is-new::before { content: ''; position: absolute; left: 0; top: 3px; bottom: 3px; width: 2px; background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.after .mono-k { margin: 0 0 8px; }

/* ---------- constraint (what-if) ---------- */
.ch-constraint { display: flex; }
.con-in { position: sticky; top: calc(var(--nav) + 6vh); align-self: flex-start; max-width: min(560px, 44vw); min-width: 0; }
.con-card { padding: 16px 18px; }
.con-card > .mono-k { margin: 0 0 10px; }
.chips { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 6px; margin: 0 0 14px; }
.chip { display: grid; gap: 3px; text-align: left; padding: 9px 11px; border-radius: var(--r); border: 1px solid var(--ln2); background: transparent; cursor: pointer; transition: border-color .3s, background .3s; }
.chip:hover { border-color: var(--ln3); }
.chip[aria-checked="true"] { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 9%, transparent); }
.chip-l { font-family: var(--font-sans); font-size: 13px; font-weight: 500; }
.chip-d { font-size: 9.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx4); }
.chip[aria-checked="true"] .chip-d { color: var(--accent); }
.con-note { margin: 12px 0 0; padding: 2px 0 2px 11px; border-left: 2px solid var(--accent); font-size: 12.5px; line-height: 1.5; color: var(--tx2); }
.con-note[data-unchanged="true"] { border-left-color: var(--ln3); }

/* ---------- the plane: pillars, dials, the finder ---------- */
.pl-in { max-width: min(560px, 44vw); display: grid; gap: 22px; }
.pillars { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; border-top: 1px solid var(--ln2); }
.pillars li { display: grid; grid-template-columns: 40px 1fr; column-gap: 12px; padding: 18px 0; border-bottom: 1px solid var(--ln); }
.pillars .label-n { grid-row: span 3; font-family: var(--font-mono); font-size: 11px; color: var(--tx3); padding-top: 4px; }
.pillars h3 { margin: 0 0 6px; font: 500 19px/1.25 var(--font-display); letter-spacing: -.01em; }
.pillars p { margin: 0; font-size: 14px; line-height: 1.55; color: var(--tx2); }
.pillars .pl-n { margin-top: 8px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx3); }
.pl-n b { font: 500 20px/1 var(--font-display); letter-spacing: -.01em; color: var(--accent); margin-right: 6px; vertical-align: -2px; }
.dials { padding: 16px 18px; }
.dl-h { margin: 0 0 10px; } .dl-h p { margin: 0 0 4px; } .dl-h .dim { font-family: var(--font-sans); font-size: 13px; line-height: 1.5; }
.dl-list { list-style: none; margin: 0 0 14px; padding: 0; }
.dl-list li { display: grid; grid-template-columns: 100px auto 1fr; gap: 12px; align-items: center; padding: 6px 0; font-size: 12px; }
.dl-list li + li { border-top: 1px solid var(--ln); }
.dl-list li.is-out .dn, .dl-list li.is-out .tl { color: var(--tx4); }   /* quieter by ink, not by opacity: still ≥ 4.5:1 */
.dn { color: var(--tx); }
.sw { display: inline-grid; grid-template-columns: 1fr 1fr; border: 1px solid var(--ln2); border-radius: var(--r); overflow: hidden; }
.sw button { padding: 5px 9px; background: transparent; border: 0; font-family: var(--font-mono); font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: var(--tx3); cursor: pointer; white-space: nowrap; }
.sw button + button { border-left: 1px solid var(--ln2); }
.sw button[aria-checked="true"] { background: color-mix(in srgb, var(--fg) 10%, transparent); color: var(--tx); }
.sw button[data-mode="auto"][aria-checked="true"] { background: color-mix(in srgb, var(--accent) 18%, transparent); color: var(--accent); }
.tl { font-size: 10.5px; color: var(--tx3); text-align: right; }
.ask-line { padding: 12px 0 0; border-top: 1px solid var(--ln2); }
.ask-line .mono-k { margin: 0 0 8px; }
.ask-line ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 6px; }
.ask-line li { display: inline-flex; align-items: center; gap: 8px; padding: 5px 10px; border-radius: var(--r); border: 1px solid var(--ln2); font-size: 11px; letter-spacing: .06em; color: var(--tx2); }
.ask-line li i { width: 8px; height: 10px; border: 1px solid var(--tx3); border-radius: 1px; position: relative; } .ask-line li i::before { content: ''; position: absolute; left: 1px; right: 1px; top: -5px; height: 5px; border: 1px solid var(--tx3); border-bottom: 0; border-radius: 4px 4px 0 0; }
.dl-out { margin: 12px 0 0; font-size: 12.5px; line-height: 1.5; color: var(--tx2); min-height: 1.5em; }
.finder { padding: 14px 18px; position: relative; }
.finder label { display: block; margin: 0 0 8px; }
.finder input { width: 100%; box-sizing: border-box; height: 40px; padding: 0 12px; border-radius: var(--r); border: 1px solid var(--ln2); background: color-mix(in srgb, var(--bg) 70%, transparent); font-family: var(--font-mono); font-size: 13px; }
.find-list { list-style: none; margin: 8px 0 0; padding: 0; max-height: 220px; overflow: auto; border: 1px solid var(--ln); border-radius: var(--r); }
.find-list li { padding: 7px 12px; font-size: 13px; cursor: pointer; display: flex; justify-content: space-between; gap: 12px; }
.find-list li span { font-family: var(--font-mono); font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: var(--tx4); white-space: nowrap; }
.find-list li[aria-selected="true"], .find-list li:hover { background: color-mix(in srgb, var(--accent) 10%, transparent); }
.find-none { margin: 8px 0 0; font-size: 12.5px; line-height: 1.5; color: var(--tx2); }
.find-none:empty { margin: 0; }

/* ---------- phase 0, system, install ---------- */
.p0-in, .sys-in { max-width: min(600px, 46vw); }
.p0-steps { list-style: none; margin: 0 0 18px; padding: 0; border-top: 1px solid var(--ln2); }
.p0-steps li { display: grid; grid-template-columns: 40px 1fr; padding: 14px 0; border-bottom: 1px solid var(--ln); }
.p0-steps .label-n { font-family: var(--font-mono); font-size: 11px; color: var(--tx3); padding-top: 3px; }
.p0-steps p { margin: 0; font-size: 15px; line-height: 1.5; color: var(--tx2); } .p0-steps b { color: var(--tx); font-weight: 500; }
.p0-list { margin: 0 0 24px; font-size: 13px; line-height: 1.7; color: var(--tx2); } .p0-list .mono-k { display: block; margin-bottom: 6px; }
.ch-system { display: flex; flex-direction: column; justify-content: flex-start; }
.sys-in { max-width: none; }
.cards { list-style: none; margin: 8px 0 18px; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; max-width: 1200px; }
.card { display: grid; gap: 10px; align-content: start; height: 100%; box-sizing: border-box; padding: 20px 20px 18px; text-decoration: none; transition: border-color .3s, transform .4s var(--ease); }
.card:hover { border-color: var(--ln3); transform: translateY(-2px); }
.card h3 { margin: 0; font: 500 21px/1.25 var(--font-display); letter-spacing: -.01em; }
.card p { margin: 0; font-size: 14px; line-height: 1.55; color: var(--tx2); }
.card-go { margin-top: 8px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); }
.sys-note { font-size: 12.5px; color: var(--tx3); max-width: 60em; }
.ch-install { display: flex; align-items: center; }
.in-in { max-width: min(640px, 50vw); min-width: 0; flex: 1 1 auto; }
.in-title { font: 500 var(--s5)/1.0 var(--font-display); letter-spacing: -.035em; margin: 0 0 22px; }
.in-title .hl { display: block; }
.harness { margin: 6px 0 22px; overflow: hidden; }
.hn-tabs { display: flex; flex-wrap: wrap; gap: 0; border-bottom: 1px solid var(--ln); }
.hn-tabs button { display: grid; gap: 2px; text-align: left; padding: 10px 14px; background: none; border: 0; border-right: 1px solid var(--ln); border-bottom: 1px solid var(--ln); margin-bottom: -1px; cursor: pointer; color: var(--tx3); }
.hn-tabs b { font: 500 13px var(--font-sans); } .hn-tabs span { font-family: var(--font-mono); font-size: 9.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--tx4); }
.hn-tabs button[aria-selected="true"] { color: var(--tx); background: color-mix(in srgb, var(--accent) 8%, transparent); box-shadow: inset 0 -2px 0 var(--accent); }
.hn-pane { padding: 16px 18px 18px; }
.hn-lead { margin: 0 0 12px; font-size: 14px; color: var(--tx2); }
.hn-steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: minmax(0, 1fr); gap: 12px; }
.hn-steps li { display: grid; grid-template-columns: minmax(0, 1fr); gap: 6px; }
.hn-steps p { margin: 0; font-size: 13px; line-height: 1.5; color: var(--tx3); }
.cmd { display: flex; align-items: center; gap: 10px; padding: 8px 8px 8px 12px; border: 1px solid var(--ln2); border-radius: var(--r); background: color-mix(in srgb, var(--bg) 70%, transparent); }
.cmd code { flex: 1; min-width: 0; font-size: 12.5px; color: var(--tx); overflow-x: auto; white-space: nowrap; }
.copy { flex: none; padding: 5px 10px; border-radius: var(--r); border: 1px solid var(--ln2); background: transparent; font-family: var(--font-mono); font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx2); cursor: pointer; }
.copy.is-done { color: var(--accent); border-color: var(--accent); }
.hn-note { margin: 14px 0 0; font-size: 12.5px; color: var(--tx3); }

/* ---------- labels in the world, the inspector ---------- */
.tags { position: fixed; inset: 0; z-index: 3; pointer-events: none; }
.tag { position: absolute; left: 0; top: 0; display: grid; gap: 2px; padding: 5px 8px; transform-origin: 0 100%; border-left: 1px solid var(--accent); background: color-mix(in srgb, var(--bg) 72%, transparent); font-size: 10.5px; line-height: 1.3; white-space: nowrap; opacity: 0; transition: opacity .35s; }
.tag b { font-weight: 500; color: var(--accent); font-variant-numeric: tabular-nums; } .tag span { color: var(--tx2); }
.tag.is-top b { font-size: 13px; }
.tip { position: fixed; z-index: 40; left: 0; top: 0; width: 300px; padding: 12px 14px; border-radius: var(--r2); border: 1px solid var(--ln2); background: color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 20px 60px -20px rgba(0, 0, 0, .9); pointer-events: none; font-size: 11px; }
.tip h4 { margin: 4px 0 6px; font: 500 15px/1.3 var(--font-sans); }
.tip p { margin: 0 0 4px; line-height: 1.45; color: var(--tx2); }
.tip .t-k { font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--tx4); }
.tip .t-s { color: var(--accent); }
.tip .t-sum { font-family: var(--font-sans); font-size: 12.5px; color: var(--tx3); }

/* ---------- footer ---------- */
.foot { position: relative; z-index: 2; padding: 64px var(--g) 36px; border-top: 1px solid var(--ln2); background: var(--bg); }
.ft-top { display: grid; grid-template-columns: minmax(260px, 1fr) 2fr; gap: 40px; margin-bottom: 44px; }
.ft-brand img { height: 28px; width: auto; }
.ft-brand p { margin: 14px 0; font-size: 16px; }
.ft-ctas { display: flex; flex-wrap: wrap; gap: 18px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; }
.ft-ctas a { text-decoration: none; color: var(--tx3); } .ft-ctas a:hover { color: var(--tx); }
.ft-cols { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 24px; }
.ft-cols .mono-k { margin: 0 0 12px; color: var(--accent); }
.ft-cols ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.ft-cols a { font-size: 13.5px; color: var(--tx2); text-decoration: none; } .ft-cols a:hover { color: var(--tx); }
.ft-bot { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px; padding-top: 20px; border-top: 1px solid var(--ln); font-size: 11px; letter-spacing: .08em; color: var(--tx3); }
.ft-bot p { margin: 0; } .ft-bot a { color: var(--tx3); text-decoration: none; } .ft-bot a:hover { color: var(--tx); }
.ft-social { display: flex; gap: 18px; }
.disclosure { max-width: 90em; margin: 24px 0 0; font-size: 12px; line-height: 1.6; color: var(--tx4); }
.disclosure a { color: var(--tx3); }

/* ---------- without WebGL: the poster behind the first screen, every panel stays readable ---------- */
.no-webgl .poster { position: absolute; inset: 0 0 auto 0; height: 100vh; }
.no-webgl .hint { display: none; }

/* ---------- laptops ---------- */
@media (max-width: 1320px) and (min-width: 821px) { .nav a { padding: 10px 8px; letter-spacing: .1em; } .sound [data-sound-label] { display: none; } }
@media (max-height: 800px) and (min-width: 821px) {
  .ch-hero { padding-bottom: 130px; } .hero-title { font-size: clamp(36px, 4.1vw, 60px); margin-bottom: 18px; } .hero-sub { margin-bottom: 22px; } .ctas { margin-bottom: 22px; } .works { margin-bottom: 10px; }
  .stats li { padding: 12px 18px 14px 0; } .stats li + li { padding-left: 18px; } .stat-t { font-size: 12px; } .hint { bottom: 132px; }
}
/* the sticky card must fit a laptop screen (up to 960 px tall) at its tallest step (commit, before and after a yes): the
   ledger scrolls inside, the rail and the card's frame are tighter; on the shortest screens a little more */
@media (max-height: 960px) and (min-width: 821px) {
  html.cp-live .sess-card { --card-top: calc(var(--nav) + 1.2vh); } .sc-body { padding: 16px 20px 14px; } .st-t { font-size: 22px; margin-bottom: 6px; } .st-p { font-size: 13.5px; margin-bottom: 12px; }
  .draft { max-height: 230px; } .files li { padding: 5px 12px; } .ranked li { padding: 6px 12px; }
  .sc-top { padding: 8px 18px; } .rail { padding: 9px 10px 7px; } .rail::before, .rail::after { top: 22px; } .rail a { gap: 5px; } .rd-n { width: 26px; height: 26px; font-size: 10px; }
  .sc-foot { height: 42px; } .st-k { margin-bottom: 6px; }
  .lines { max-height: 80px; } .ledger { padding: 8px 12px; margin-bottom: 10px; } .ledger .src { margin-top: 8px; } .lg-h { margin-bottom: 6px; }
  .c-wait { padding: 7px 10px; margin-bottom: 10px; font-size: 12.5px; }
  .after .mono-k { margin-bottom: 6px; } .ranked.is-small li { padding: 3px 10px; }
}
@media (max-height: 800px) and (min-width: 821px) {
  .sc-body { padding: 12px 20px 10px; } .st-p { font-size: 13px; line-height: 1.5; margin-bottom: 10px; } .lines { max-height: 66px; } .ledger .src { font-size: 10px; line-height: 1.45; }
  .c-wait { line-height: 1.4; } .ranked.is-small li { padding: 2px 10px; } .ranked.is-small .rk-t b { font-size: 12px; }
}

/* ---------- phones: the world above, the words below (re-framed, not shrunk) ---------- */
@media (max-width: 820px) {
  :root { --nav: 58px; }
  .top { grid-template-columns: auto 1fr; gap: 12px; }
  .top-r { justify-self: end; gap: 8px; }
  /* the chapters open under the header from the Menu button */
  .menu-btn { display: inline-flex; order: 3; }
  .nav { display: none; position: fixed; z-index: 29; top: var(--nav); left: 0; right: 0; flex-direction: column; gap: 0; padding: 6px var(--g) 16px;
    background: color-mix(in srgb, var(--bg) 95%, transparent); border-bottom: 1px solid var(--ln2); box-shadow: 0 30px 60px -30px rgba(0, 0, 0, .9); }
  html.menu-open .nav { display: flex; }
  .nav a { padding: 15px 0; font-size: 12px; color: var(--tx2); border-bottom: 1px solid var(--ln); }
  .nav a:last-child { border-bottom: 0; }
  .nav a[aria-current]::after { left: 0; right: auto; width: 22px; bottom: 7px; }
  .sound { height: 34px; } .sound [data-sound-label] { display: none; }
  .brand img { height: 22px; }
  .ch { padding: calc(var(--nav) + 5vh) var(--g) 8vh; }
  /* the hero's shade is set in screens (its words start at 40svh) and fades out below its last words, like the chapters' */
  .ch-hero { justify-content: flex-start; padding-top: 40svh; padding-bottom: 22vh; min-height: 100svh; }
  .ch-hero::before { width: 100%; background: linear-gradient(to bottom, transparent 34vh, color-mix(in srgb, var(--bg) 70%, transparent) 64vh, color-mix(in srgb, var(--bg) 86%, transparent) 107vh, color-mix(in srgb, var(--bg) 86%, transparent) calc(100% - 20vh), transparent 100%); }
  .stats::before { display: none; }   /* the hero's own shade holds the facts row on phones; a second one would end in a hard edge */
  .in-title { font-size: clamp(32px, 9.4vw, 44px); }
  /* the shades behind the words start where the words start (in screens, not in shares of a tall chapter) */
  .ch-install::before { width: 100%; background: linear-gradient(to bottom, transparent 22vh, color-mix(in srgb, var(--bg) 88%, transparent) 40vh, color-mix(in srgb, var(--bg) 88%, transparent) calc(100% - 16vh), var(--bg) 100%); }   /* into the footer's ground without a step */
  .tags { display: none; }
  /* ... and fade out again before the chapter ends: no full-width step in the light where the next chapter starts (the
     chapter's bottom padding keeps its last words on the full shade) */
  .ch-constraint::before, .ch-plane::before, .ch-phase0::before, .ch-system::before { width: 100%; background: linear-gradient(to bottom, transparent 28vh, color-mix(in srgb, var(--bg) 86%, transparent) 45vh, color-mix(in srgb, var(--bg) 86%, transparent) calc(100% - 22vh), transparent 100%); }
  /* full under the words, with long fades (12vh) above and below them: over the lit plane a short fade reads as an edge */
  .ch-session .sess-head::before { right: calc(-1 * var(--g)); width: auto; top: -12vh; bottom: -12vh; background: color-mix(in srgb, var(--bg) 84%, transparent);
    -webkit-mask-image: linear-gradient(to bottom, transparent, #000 12vh, #000 calc(100% - 12vh), transparent); mask-image: linear-gradient(to bottom, transparent, #000 12vh, #000 calc(100% - 12vh), transparent); }
  .hero-in { max-width: none; }
  .hero-title { font-size: clamp(34px, 10vw, 46px); }
  .hero-sub { font-size: 15.5px; }
  .ctas .btn { flex: 1 1 auto; justify-content: center; }
  .stats { position: relative; left: auto; right: auto; bottom: auto; grid-template-columns: 1fr 1fr; margin-top: 28px; }
  .stats li:nth-child(3) { padding-left: 0; border-left: 0; } .stats li:nth-child(n+3) { border-top: 1px solid var(--ln); }
  .hint { display: none; }
  .sess-card { width: auto; }
  .sess-head { margin-bottom: 0; }
  /* phones: each step is its own screen: the world in the top half, its card below */
  .sc-body { padding: 0; }
  .step { min-height: 100svh; box-sizing: border-box; display: flex; flex-direction: column; justify-content: flex-end; padding: 46vh 18px 22px !important; margin: 0 !important; border: 0 !important; }
  .step > * { position: relative; }
  /* the shade under a step's words starts a little above them (not a share of the step: steps differ in length), so the
     words are always on it and the world above them stays clear */
  .step::before { content: ''; position: absolute; left: 0; right: 0; bottom: 0; top: calc(46vh - 92px); z-index: 0; background: linear-gradient(to bottom, transparent, color-mix(in srgb, var(--bg) 88%, transparent) 76px); pointer-events: none; }
  .step { position: relative; }
  .sess-card { background: none; border: 0; box-shadow: none; backdrop-filter: none; -webkit-backdrop-filter: none; overflow: visible; }
  /* only the rail stays under the header (the company line scrolls away with the intro): more of the world shows */
  .sc-top { position: static; flex-wrap: wrap; gap: 2px 12px; padding: 8px 18px; background: color-mix(in srgb, var(--bg) 88%, transparent); } .sc-top .dots { display: none; } .sc-top .mono-k { font-size: 9.5px; letter-spacing: .12em; } .sc-src { margin-left: 0; }
  .rail { position: sticky; top: var(--nav); z-index: 3; background: color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); padding: 10px 4px 8px; }
  .rail::before, .rail::after { top: 24px; } .rd-n { width: 26px; height: 26px; }
  .sc-foot { display: none; }
  .personas { grid-template-columns: 1fr; }
  .con-in, .pl-in, .p0-in, .in-in { max-width: none; position: static; }
  .ch-constraint, .ch-plane, .ch-phase0, .ch-system { padding-top: 48vh; padding-bottom: 24vh; min-height: 0; }
  .st-ex { display: block; }
  .chips { grid-template-columns: 1fr 1fr; }
  .dl-list li { grid-template-columns: 1fr auto; } .dl-list .tl { grid-column: 1 / -1; text-align: left; }
  .cards { grid-template-columns: 1fr; }
  .ch-install { padding-top: 44vh; }
  .ft-top { grid-template-columns: 1fr; } .ft-cols { grid-template-columns: 1fr 1fr; }
  .tip { left: 12px !important; right: 12px; top: auto !important; bottom: 12px; width: auto; transform: none !important; }
  .ranked li { grid-template-columns: 26px 1fr 96px; }
}