/* WHY — why.com — site styles (v2: paper-white, ultramarine / vermilion / gold, dot-matrix receipts).
   No build step: edit and upload. Colours and fonts are the variables below. */

:root {
  --paper: #ffffff;
  --paper-2: #f5f4ef;
  --paper-3: #ecebe4;
  --ink: #0b0d14;
  --ink-2: #2c2f3a;
  --mid: #6b6f7c;
  --dim: #a3a6b0;
  --line: #e3e2dc;
  --line-2: #c9c8c0;
  --blue: #2a39ff;
  --blue-2: #8f98ff;
  --blue-soft: #eceeff;
  --red: #ff4b2b;
  --red-soft: #ffece7;
  --yellow: #ffc82e;
  --yellow-soft: #fff5d1;
  --gold: #e3ac12;            /* the logo's dot on a light page */
  --green: #0f9d58;
  --serif: "Cormorant Garamond", "EB Garamond", Georgia, "Times New Roman", serif;
  --sans: "Geist", "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --dot: "Doto", "Geist Mono", ui-monospace, Menlo, Consolas, monospace;   /* dot-matrix: labels, numerals, receipts */
  --max: 1280px;
  --gutter: clamp(20px, 4.4vw, 64px);
  --nav-h: 64px;
  --ease: cubic-bezier(.16, 1, .3, 1);
  --ease-io: cubic-bezier(.65, 0, .35, 1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 24px); -webkit-text-size-adjust: 100%; }
body { min-width: 320px; overflow-x: hidden; background: var(--paper); color: var(--ink); font-family: var(--sans); font-size: 16px; line-height: 1.45; letter-spacing: -.011em; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
a { color: inherit; text-decoration: none; }
img, svg, canvas { display: block; max-width: 100%; }
button { font: inherit; color: inherit; cursor: pointer; background: none; border: 0; letter-spacing: inherit; }
::selection { background: var(--yellow); color: var(--ink); }
:focus-visible { outline: 2px solid var(--blue); outline-offset: 3px; }
.skip { position: absolute; left: -999px; top: 8px; z-index: 3000; padding: 10px 14px; background: var(--ink); color: #fff; font-size: .85rem; }
.skip:focus { left: 8px; }
.wrap { width: 100%; max-width: calc(var(--max) + 2 * var(--gutter)); margin: 0 auto; padding: 0 var(--gutter); }
.nowrap { white-space: nowrap; }

/* ───────────── type */
h1, h2, h3, h4 { font-weight: 500; letter-spacing: -.03em; line-height: 1.02; text-wrap: balance; }
h3 { font-size: 1.3rem; letter-spacing: -.02em; line-height: 1.12; }
p { text-wrap: pretty; }
.serif { font-family: var(--serif); }
.t-title { font-size: clamp(1.25rem, 1.6vw, 1.4rem); font-weight: 500; letter-spacing: -.02em; line-height: 1.1; }
.t-desc { margin-top: 8px; max-width: 34ch; color: var(--ink-2); font-size: 1rem; line-height: 1.22; letter-spacing: -.015em; }
.t-statement { font-family: var(--serif); font-weight: 500; font-size: clamp(1.9rem, 3.5vw, 3.1rem); line-height: 1.04; letter-spacing: -.022em; text-wrap: balance; }
.lbl { display: inline-block; font-family: var(--dot); font-weight: 800; font-size: .78rem; letter-spacing: .02em; line-height: 1; white-space: nowrap; }
.tab { position: absolute; top: 0; left: 0; z-index: 2; transform: translateY(-100%); padding: 6px 9px 5px; border: 1px solid var(--line-2); border-bottom: 0; background: var(--paper-2); color: var(--ink-2); font-family: var(--dot); font-weight: 800; font-size: .74rem; letter-spacing: .02em; line-height: 1; white-space: nowrap; }
.hl { position: relative; white-space: nowrap; z-index: 0; }
.hl::before { content: ""; position: absolute; z-index: -1; left: -.06em; right: -.06em; bottom: .06em; height: .42em; background: var(--yellow); transform: scaleX(0); transform-origin: left; transition: transform .7s var(--ease) .15s; }
.in .hl::before, .hl.in::before { transform: scaleX(1); }

/* ───────────── buttons and links */
.btn { position: relative; display: inline-flex; align-items: center; gap: .6em; height: 40px; padding: 0 14px; overflow: hidden; isolation: isolate; border: 1px solid var(--ink); background: var(--ink); color: #fff; font-size: .9rem; font-weight: 500; letter-spacing: -.01em; white-space: nowrap; transition: color .25s; }
.btn::before { content: ""; position: absolute; inset: 0; z-index: -1; background: var(--blue); transform: translateY(101%); transition: transform .35s var(--ease); }
.btn:hover::before { transform: none; }
.btn svg { width: 13px; height: 13px; transition: transform .3s var(--ease); }
.btn:hover svg { transform: translate(2px, -2px); } .btn:hover svg.e { transform: translate(3px, 0); }
.btn.ghost { background: transparent; color: var(--ink); }
.btn.ghost::before { background: var(--yellow); }
.btn.lg { height: 46px; padding: 0 18px; font-size: .95rem; }
.link { display: inline-flex; align-items: center; gap: .45em; font-weight: 500; font-size: .95rem; border-bottom: 1px solid var(--ink); padding-bottom: 1px; transition: color .2s, border-color .2s; }
.link svg { width: 12px; height: 12px; transition: transform .3s var(--ease); }
.link:hover { color: var(--blue); border-color: var(--blue); } .link:hover svg { transform: translate(2px, -2px); } .link:hover svg.e { transform: translate(3px, 0); }

/* ───────────── intro splash (home page only; pure CSS, so it can never get stuck) */
.splash { position: fixed; inset: 0; z-index: 2000; display: grid; place-items: center; background: var(--paper); pointer-events: none; animation: introOut .7s var(--ease-io) 1.15s forwards; }
.splash-mark { font-family: "Cormorant Garamond", serif; font-weight: 600; font-size: clamp(4rem, 15vw, 11rem); letter-spacing: .06em; line-height: 1; color: var(--ink); display: flex; align-items: baseline; }
.splash-mark span { display: inline-block; opacity: 0; transform: translateY(.35em); animation: introLetter .5s var(--ease) forwards; }
.splash-mark span:nth-child(2) { animation-delay: .07s; } .splash-mark span:nth-child(3) { animation-delay: .14s; }
.splash-mark i { display: inline-block; width: .17em; height: .17em; margin-left: .05em; border-radius: 50%; background: var(--gold); transform: translateY(-4.2em); animation: introDot .62s cubic-bezier(.3, 1.5, .5, 1) .34s forwards; }
@keyframes introLetter { to { opacity: 1; transform: none; } }
@keyframes introDot { 0% { transform: translateY(-4.2em); } 60% { transform: translateY(0) scale(1.25, .8); } 100% { transform: none; } }
@keyframes introOut { to { transform: translateY(-101%); visibility: hidden; } }
.seen .splash { display: none; }

/* ───────────── nav */
.nav { position: fixed; inset: 0 0 auto 0; z-index: 500; height: var(--nav-h); border-bottom: 1px solid transparent; transition: background .3s, border-color .3s; }
.nav.scrolled, .nav.solid { background: rgba(255, 255, 255, .86); border-bottom-color: var(--line); -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px); }
.nav .wrap { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; height: 100%; gap: 24px; }
/* The logo: the old why.com wordmark, in ink on the light page */
.nav-logo { justify-self: start; font-family: "Cormorant Garamond", serif; font-size: 1.75rem; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; color: var(--ink); line-height: 1; }
.nav-logo em { color: var(--gold); font-style: normal; }
.nav-links { display: flex; align-items: center; gap: clamp(16px, 2.4vw, 34px); list-style: none; }
.nav-links a { display: inline-flex; align-items: center; gap: .55em; padding: 8px 0; font-size: .9rem; font-weight: 500; color: var(--ink); }
.nav-links a::before { content: ""; width: 7px; height: 7px; border-radius: 50%; border: 1px solid var(--ink); transition: background .2s, border-color .2s, transform .3s var(--ease); }
.nav-links a:hover::before, .nav-links a[aria-current="page"]::before { background: var(--red); border-color: var(--red); transform: scale(1.25); }
.nav-right { justify-self: end; display: flex; align-items: center; gap: 10px; }
.nav-toggle { display: none; width: 40px; height: 40px; border: 1px solid var(--ink); align-items: center; justify-content: center; }
.nav-toggle span { display: block; width: 16px; height: 1.5px; background: var(--ink); box-shadow: 0 5px 0 var(--ink), 0 -5px 0 var(--ink); transition: all .25s; }
.nav-toggle[aria-expanded="true"] span { box-shadow: none; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { content: ""; display: block; width: 16px; height: 1.5px; background: var(--ink); transform: rotate(-90deg); }
.mobile-menu { position: fixed; inset: var(--nav-h) 0 0 0; z-index: 490; display: none; flex-direction: column; padding: 18px var(--gutter) 40px; background: var(--paper); overflow-y: auto; }
.mobile-menu.open { display: flex; }
.mobile-menu a { display: flex; justify-content: space-between; align-items: center; padding: 18px 0; border-bottom: 1px solid var(--line); font-size: 1.7rem; font-weight: 500; letter-spacing: -.03em; }
.mobile-menu a span { font-family: var(--dot); font-weight: 800; font-size: .8rem; color: var(--mid); }

/* ───────────── hero */
.hero { position: relative; padding-top: var(--nav-h); overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); align-items: center; gap: clamp(20px, 4vw, 72px); min-height: min(760px, calc(100svh - var(--nav-h) - 40px)); padding-top: 34px; padding-bottom: 34px; }
.hero h1 { font-size: clamp(2.6rem, 5.3vw, 4.6rem); letter-spacing: -.035em; line-height: 1; }
.js-type .hero h1 { visibility: hidden; animation: forceShow 0s linear 4s forwards; }
@keyframes forceShow { to { visibility: visible; } }
.hero h1 .ch { color: var(--dim); transition: color .5s ease; } .hero h1 .ch.on { color: var(--ink); } .hero h1 .ch.off { visibility: hidden; }
.hero h1 em { font-family: var(--serif); font-style: italic; font-weight: 500; font-size: 1.1em; letter-spacing: -.02em; padding-right: .05em; }
.hero-after { opacity: 0; transform: translateY(18px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.hero-after.in { opacity: 1; transform: none; }
.hero-after p { margin-top: 22px; max-width: 27em; color: var(--ink-2); font-size: clamp(1.05rem, 1.35vw, 1.2rem); line-height: 1.3; letter-spacing: -.015em; }
.hero-after p strong { color: var(--ink); font-weight: 600; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }
/* the layered card stack */
.stack { position: relative; width: 100%; max-width: 640px; aspect-ratio: 1 / .96; justify-self: end; margin: 26px 0; }
.stack-main { position: absolute; inset: 4% 9% 7% 7%; z-index: 2; border: 1px solid var(--line-2); background: var(--paper); }
.stack-main canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
.stack-card { position: absolute; z-index: 1; border: 1px solid; background: var(--paper); }
.stack-verify { top: 0; right: 0; width: 30%; min-width: 150px; z-index: 3; border-color: var(--ink); background: var(--yellow); padding: 11px 13px 12px; transition: transform .6s var(--ease); }
.stack-verify .lbl { display: block; color: var(--ink); font-size: .68rem; white-space: normal; line-height: 1.15; }
.stack-verify b { display: block; margin-top: 10px; font-family: var(--dot); font-weight: 900; font-size: clamp(1.9rem, 3.4vw, 2.9rem); line-height: .8; color: var(--ink); }
.stack-verify b i { display: inline-block; width: .2em; height: .2em; margin-left: .1em; background: var(--ink); animation: blink 1.2s steps(1) infinite; }
.stack:hover .stack-verify { transform: translate(6px, -6px); }
/* the receipt that prints out of the stack */
.receipt { position: absolute; left: 0; bottom: 0; z-index: 3; width: 44%; min-width: 196px; padding: 12px 13px 46px; background: var(--paper); border: 1px solid var(--ink); border-bottom: 0; font-family: var(--dot); font-weight: 800; font-size: clamp(.62rem, .86vw, .76rem); line-height: 1.5; color: var(--ink); transition: transform .6s var(--ease); }
.receipt::after { content: ""; position: absolute; left: -1px; right: -1px; bottom: -7px; height: 8px; background: linear-gradient(135deg, var(--paper) 5.5px, transparent 0) 0 0 / 11px 8px, linear-gradient(-135deg, var(--paper) 5.5px, transparent 0) 0 0 / 11px 8px; filter: drop-shadow(0 1px 0 var(--ink)); }
.stack:hover .receipt { transform: translate(-6px, 6px); }
.receipt-head { display: flex; justify-content: space-between; padding-bottom: 6px; margin-bottom: 6px; border-bottom: 1px dashed var(--line-2); color: var(--mid); }
.receipt-line { display: flex; justify-content: space-between; gap: 10px; white-space: nowrap; overflow: hidden; opacity: 0; transform: translateY(-4px); transition: opacity .2s, transform .25s var(--ease); }
.receipt-line.on { opacity: 1; transform: none; }
.receipt-line span:first-child { color: var(--mid); } .receipt-line span:last-child { overflow: hidden; text-overflow: ellipsis; }
.receipt-line .block { color: var(--red); } .receipt-line .allow { color: var(--green); } .receipt-line .l4 { background: var(--yellow); padding: 0 4px; }
.receipt-note { margin-top: 6px; padding-top: 6px; border-top: 1px dashed var(--line-2); color: var(--mid); min-height: 2.9em; white-space: normal; line-height: 1.25; }
.stamp { position: absolute; right: 10px; bottom: 14px; padding: 4px 7px 3px; border: 2px solid var(--blue); color: var(--blue); font-family: var(--dot); font-weight: 900; font-size: 1.05em; letter-spacing: .04em; line-height: 1; transform: rotate(-9deg) scale(2.4); opacity: 0; }
.stamp.on { opacity: 1; transform: rotate(-9deg) scale(1); transition: transform .28s cubic-bezier(.2, 1.6, .4, 1), opacity .1s; }

/* ticker */
.ticker { border-top: 1px solid var(--ink); border-bottom: 1px solid var(--ink); overflow: hidden; }
.ticker-track { display: flex; width: max-content; animation: ticker 52s linear infinite; }
.ticker:hover .ticker-track { animation-play-state: paused; }
.ticker span { display: inline-flex; align-items: center; gap: 22px; padding: 11px 11px; font-family: var(--dot); font-weight: 800; font-size: .92rem; letter-spacing: .02em; white-space: nowrap; }
.ticker span::after { content: ""; width: 9px; height: 9px; background: var(--yellow); border-radius: 50%; }
.ticker span:nth-child(3n)::after { background: var(--blue); border-radius: 0; } .ticker span:nth-child(3n+1)::after { background: var(--red); border-radius: 0; transform: rotate(45deg); }
@keyframes ticker { to { transform: translateX(-50%); } }

/* ───────────── sections */
.section { position: relative; padding-top: clamp(84px, 10vw, 150px); }
.section.tight { padding-top: clamp(56px, 6vw, 90px); }
.section-head { display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-bottom: clamp(34px, 4vw, 54px); }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(28px, 6vw, 110px); align-items: start; }
.split .sticky { position: sticky; top: calc(var(--nav-h) + 36px); }

/* statement + feature cards */
.statement-grid { display: grid; grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr); gap: clamp(28px, 6vw, 110px); align-items: end; padding-top: clamp(34px, 5vw, 70px); }
.statement-grid .t-statement { font-size: clamp(1.6rem, 2.5vw, 2.15rem); line-height: 1.05; max-width: 21em; }
.statement-grid .t-statement .w { color: var(--line-2); transition: color .35s ease; } .statement-grid .t-statement .w.on { color: var(--ink); }
.feature-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.feature-card { position: relative; display: grid; grid-template-columns: 72px 1fr; min-height: 72px; border: 1px solid var(--line); background: var(--paper); transition: border-color .2s; }
.feature-card:hover { border-color: var(--ink); }
.feature-card .thumb { display: grid; place-items: center; overflow: hidden; }
.feature-card .thumb svg { width: 100%; height: 100%; }
.feature-card .txt { padding: 8px 26px 8px 12px; display: flex; flex-direction: column; justify-content: space-between; gap: 6px; }
.feature-card .lbl { color: var(--mid); font-size: .68rem; }
.feature-card strong { font-family: var(--dot); font-weight: 800; font-size: .76rem; line-height: 1.18; letter-spacing: .01em; }
.feature-card .go { position: absolute; top: 8px; right: 8px; width: 10px; height: 10px; transition: transform .3s var(--ease); }
.feature-card:hover .go { transform: translate(2px, -2px); color: var(--blue); }

/* in plain words: one receipt, graded line by line. Same parts as the rest of the page: a bordered card with a label tab. */
.graded { position: relative; margin-top: 8px; border: 1px solid var(--line-2); background: var(--paper); }
.graded-row { display: grid; grid-template-columns: 1fr auto; gap: 16px; align-items: center; min-height: 64px; padding: 12px 16px; border-bottom: 1px solid var(--line); transition: background .3s; }
.graded-row p { font-size: clamp(1.1rem, 1.55vw, 1.32rem); font-weight: 500; letter-spacing: -.02em; line-height: 1.12; }
.graded-row:hover { background: var(--paper-2); }
.graded-row.proven, .graded-row.proven:hover { background: var(--yellow-soft); }
.grade { display: inline-flex; align-items: center; gap: 10px; font-family: var(--dot); font-weight: 900; font-size: .84rem; white-space: nowrap; }
.steps { display: inline-flex; gap: 4px; }
.steps i { width: 12px; height: 12px; border: 1px solid var(--ink); transform: scale(.4); opacity: 0; transition: transform .45s cubic-bezier(.2, 1.6, .4, 1), opacity .2s; }
.steps i.on { background: var(--ink); } .graded-row.proven .steps i.on { background: var(--yellow); }
.graded.in .steps i, .no-js .steps i { transform: none; opacity: 1; }
.graded-row:nth-of-type(1) .steps i { transition-delay: .3s; } .graded-row:nth-of-type(2) .steps i { transition-delay: .48s; }
.graded-row:nth-of-type(3) .steps i { transition-delay: .66s; } .graded-row:nth-of-type(4) .steps i { transition-delay: .84s; }
.graded-key { display: flex; flex-wrap: wrap; gap: 6px 24px; padding: 12px 16px 11px; font-family: var(--dot); font-weight: 800; font-size: .72rem; line-height: 1.2; color: var(--mid); }
.graded-key b { margin-right: 7px; font-weight: 900; color: var(--ink); }

/* principles */
.principles { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.principle .art { position: relative; aspect-ratio: 1 / .78; border: 1px solid var(--line); background: var(--paper); overflow: hidden; transition: border-color .25s, background .25s; }
.principle:hover .art { border-color: var(--ink); }
.principle .art svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.principle h3 { margin-top: 14px; font-size: 1.05rem; font-weight: 500; }
.principle p { margin-top: 6px; color: var(--mid); font-size: .92rem; line-height: 1.3; }
.principle p b { color: var(--ink); font-weight: 500; }

/* technology rows */
.tech-list { display: grid; gap: 30px; padding-top: 8px; }
.tech-row { position: relative; display: grid; grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr) 18px; gap: 20px; align-items: center; min-height: 96px; padding: 18px 16px; border: 1px solid var(--line-2); background: var(--paper); transition: background .3s, border-color .3s; }
.tech-row h3 { font-size: clamp(1.3rem, 1.9vw, 1.65rem); font-weight: 500; }
.tech-row p { color: var(--ink-2); font-size: .95rem; line-height: 1.25; }
.tech-row .go { width: 14px; height: 14px; transition: transform .3s var(--ease); }
.tech-row .tab { transition: background .3s, color .3s, border-color .3s; }
a.tech-row:hover { background: var(--yellow-soft); border-color: var(--ink); }
a.tech-row:hover .tab { background: var(--ink); color: #fff; border-color: var(--ink); }
a.tech-row:hover .go { transform: translate(3px, -3px); }

/* carousel */
.arrows { display: flex; gap: 8px; }
.arrows button { width: 40px; height: 40px; border: 1px solid var(--line-2); display: grid; place-items: center; transition: background .2s, border-color .2s, color .2s; }
.arrows button:hover { background: var(--ink); border-color: var(--ink); color: #fff; }
.arrows svg { width: 13px; height: 13px; }
.uc-track { display: grid; grid-auto-flow: column; grid-auto-columns: calc((100% - 3 * 20px) / 3.4); gap: 20px; overflow-x: auto; scroll-snap-type: x mandatory; scrollbar-width: none; margin: 0 calc(-1 * var(--gutter)); padding: 0 var(--gutter) 6px; scroll-padding-left: var(--gutter); }
.uc-track::-webkit-scrollbar { display: none; }
.uc { scroll-snap-align: start; }
.uc-art { position: relative; aspect-ratio: 1 / .76; border: 1px solid var(--line-2); background: var(--paper); overflow: hidden; transition: border-color .25s; }
.uc:hover .uc-art { border-color: var(--ink); }
.uc-art svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.uc h3 { margin-top: 14px; font-size: 1.05rem; font-weight: 500; }
.uc p { margin-top: 6px; max-width: 40ch; font-family: var(--mono); font-size: .78rem; line-height: 1.4; letter-spacing: -.02em; color: var(--ink-2); }
.status { display: inline-flex; align-items: center; gap: 7px; margin-top: 10px; padding: 4px 8px 3px; border: 1px solid var(--line-2); font-family: var(--dot); font-weight: 800; font-size: .7rem; line-height: 1; }
.status::before { content: ""; width: 7px; height: 7px; background: var(--mid); }
.status.done::before { background: var(--green); } .status.proto::before { background: var(--blue); } .status.open::before { background: transparent; border: 1px dashed var(--ink); }

/* evidence levels: expanding panels */
.levels { display: flex; gap: 10px; height: 470px; }
.level { position: relative; flex: 1 1 0; min-width: 0; overflow: hidden; border: 1px solid var(--line-2); background: var(--paper); text-align: left; transition: flex-grow .65s var(--ease), background .4s, border-color .3s; }
.level.open { flex-grow: 5.2; border-color: var(--ink); }
.level.l1 { background: var(--paper-2); } .level.l2 { background: var(--blue-soft); } .level.l4 { background: var(--yellow); } .level.l3, .level.l5 { border-style: dashed; }
.level-closed { position: absolute; inset: 0; width: 100%; display: flex; flex-direction: column; justify-content: space-between; padding: 18px 16px; text-align: left; transition: opacity .25s; }
.level-closed b { font-family: var(--dot); font-weight: 900; font-size: 2.2rem; line-height: .9; }
.level-closed span { writing-mode: vertical-rl; transform: rotate(180deg); align-self: flex-start; font-size: 1.02rem; font-weight: 500; letter-spacing: -.01em; white-space: nowrap; }
.level.open .level-closed { opacity: 0; pointer-events: none; }
.level-open { position: absolute; inset: 0; width: calc((min(var(--max), 100vw - 2 * var(--gutter)) - 40px) * .565 - 2px); display: grid; grid-template-columns: auto 1fr; grid-template-rows: auto 1fr auto; gap: 6px 26px; padding: 22px 24px 22px; opacity: 0; transition: opacity .3s; pointer-events: none; }
.level.open .level-open { opacity: 1; transition: opacity .5s .2s; pointer-events: auto; }
.level-open .num { grid-row: 1 / 3; font-family: var(--dot); font-weight: 900; font-size: clamp(5rem, 10vw, 9rem); line-height: .8; letter-spacing: -.04em; }
.level-open h3 { align-self: end; padding-right: 128px; font-size: clamp(1.5rem, 2.4vw, 2.1rem); }
.level-open .def { font-family: var(--serif); font-weight: 500; font-size: clamp(1.15rem, 1.6vw, 1.42rem); line-height: 1.12; letter-spacing: -.012em; max-width: 26em; }
.meter { display: flex; gap: 6px; margin-top: 18px; } .meter i { width: 40px; height: 12px; border: 1px solid var(--ink); } .meter i.on { background: var(--ink); }
.level-open dl { grid-column: 1 / -1; display: grid; grid-template-columns: 1fr 1fr; gap: 18px; padding-top: 14px; border-top: 1px solid rgba(11, 13, 20, .22); }
.level-open dt { font-family: var(--dot); font-weight: 800; font-size: .72rem; color: var(--ink-2); margin-bottom: 5px; }
.level-open dd { font-size: .92rem; line-height: 1.28; }
.level-open code, .lab code, .article code, .lim code { font-family: var(--mono); font-size: .86em; background: rgba(11, 13, 20, .07); padding: .08em .34em; }
.level-chip { position: absolute; top: 18px; right: 18px; padding: 4px 8px 3px; border: 1px solid var(--ink); font-family: var(--dot); font-weight: 800; font-size: .7rem; line-height: 1; background: var(--paper); opacity: 0; transition: opacity .3s .25s; }
.level.open .level-chip { opacity: 1; }

/* forgery lab */
.lab { display: grid; grid-template-columns: minmax(0, .86fr) minmax(0, 1.14fr); gap: clamp(28px, 5vw, 90px); align-items: start; }
.paper { position: relative; padding: 20px 20px 30px; background: var(--paper); border: 1px solid var(--ink); border-bottom: 0; font-family: var(--dot); font-weight: 800; font-size: clamp(.74rem, 1vw, .88rem); line-height: 1.55; }
.paper::after { content: ""; position: absolute; left: -1px; right: -1px; bottom: -9px; height: 10px; background: linear-gradient(135deg, var(--paper) 7px, transparent 0) 0 0 / 14px 10px, linear-gradient(-135deg, var(--paper) 7px, transparent 0) 0 0 / 14px 10px; filter: drop-shadow(0 1px 0 var(--ink)); }
.paper-wrap { position: relative; padding: 26px clamp(14px, 3vw, 44px) 40px; background: var(--paper-2); border: 1px solid var(--line); background-image: radial-gradient(var(--line-2) 1px, transparent 1.2px); background-size: 14px 14px; }
.paper header { display: flex; justify-content: space-between; align-items: baseline; padding-bottom: 8px; margin-bottom: 8px; border-bottom: 1px dashed var(--ink); }
.paper header b { font-family: "Cormorant Garamond", serif; font-weight: 600; font-size: 1.5rem; letter-spacing: .06em; } .paper header b i { color: var(--gold); font-style: normal; }
.paper .row { display: flex; justify-content: space-between; gap: 14px; padding: 1px 4px; margin: 0 -4px; transition: background .25s, color .25s; }
.paper .row > span:first-child { color: var(--mid); flex: none; } .paper .row > span:last-child { text-align: right; overflow-wrap: anywhere; }
.paper .row.hit { background: var(--red); color: #fff; } .paper .row.hit > span:first-child { color: #fff; }
.paper .rule { margin: 8px 0; border-top: 1px dashed var(--ink); }
.paper .claim { display: grid; grid-template-columns: 26px 1fr auto; gap: 8px; padding: 1px 4px; margin: 0 -4px; }
.paper .claim b { padding: 0 5px; background: var(--paper-3); font-weight: 900; } .paper .claim b.l4 { background: var(--yellow); }
.paper .claim.hit b { background: var(--red); color: #fff; }
.paper .big-stamp { position: absolute; right: 16px; bottom: 44px; z-index: 2; padding: 8px 12px 6px; border: 3px solid var(--green); color: var(--green); background: rgba(255, 255, 255, .82); font-weight: 900; font-size: 1.9em; letter-spacing: .04em; line-height: 1; transform: rotate(-8deg) scale(2.6); opacity: 0; pointer-events: none; }
.paper .big-stamp.on { opacity: 1; transform: rotate(-8deg) scale(1); transition: transform .3s cubic-bezier(.2, 1.7, .4, 1), opacity .08s; }
.paper .big-stamp.bad { border-color: var(--red); color: var(--red); }
.paper.shake { animation: shake .34s linear; }
@keyframes shake { 20% { transform: translate(-5px, 1px) rotate(-.6deg); } 40% { transform: translate(5px, -1px) rotate(.6deg); } 60% { transform: translate(-3px, 0); } 80% { transform: translate(3px, 0); } }
.lab-side .t-statement { margin: 0 0 16px; }
.lab-side > p { color: var(--ink-2); max-width: 36em; line-height: 1.3; }
.attacks { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 24px; }
.attack { position: relative; display: flex; align-items: center; gap: 10px; min-height: 52px; padding: 9px 12px; border: 1px solid var(--line-2); background: var(--paper); text-align: left; font-size: .9rem; font-weight: 500; line-height: 1.15; transition: border-color .2s, background .2s, color .2s; }
.attack i { flex: none; font-family: var(--dot); font-style: normal; font-weight: 900; font-size: .8rem; color: var(--red); }
.attack:hover { border-color: var(--ink); background: var(--red-soft); }
.attack[aria-pressed="true"] { background: var(--ink); border-color: var(--ink); color: #fff; }
.attack.honest i { color: var(--green); } .attack.honest:hover { background: var(--yellow-soft); } .attack.honest { grid-column: 1 / -1; }
.verdict { position: relative; margin-top: 30px; padding: 14px 16px; min-height: 86px; border: 1px solid var(--ink); background: var(--paper); font-family: var(--mono); font-size: .82rem; line-height: 1.5; }
.verdict .who { display: block; font-family: var(--sans); font-size: .9rem; color: var(--ink-2); margin-top: 6px; }
.verdict .bad { color: var(--red); font-weight: 500; } .verdict .ok { color: var(--green); font-weight: 500; }
.lab-note { margin-top: 12px; font-size: .82rem; color: var(--mid); } .lab-note a { border-bottom: 1px solid var(--line-2); } .lab-note a:hover { color: var(--blue); }

/* built on */
.built { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.built a { position: relative; display: flex; flex-direction: column; justify-content: center; gap: 6px; min-height: 142px; padding: 18px 22px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); overflow: hidden; transition: background .3s; }
.built a b { font-size: clamp(1.25rem, 2vw, 1.8rem); font-weight: 600; letter-spacing: -.04em; line-height: 1; transition: transform .4s var(--ease); }
.built a span { font-family: var(--dot); font-weight: 800; font-size: .72rem; color: var(--mid); transition: transform .4s var(--ease), color .3s; }
.built a:hover { background: var(--paper-2); } .built a:hover b { transform: translateX(6px); } .built a:hover span { transform: translateX(6px); color: var(--ink); }
.built a:nth-child(2) b { font-family: var(--mono); font-weight: 500; letter-spacing: -.06em; } .built a:nth-child(3) b { font-family: var(--serif); font-size: clamp(1.5rem, 2.4vw, 2.2rem); font-weight: 600; }
.built a:nth-child(5) b, .built a:nth-child(6) b { font-family: var(--dot); font-weight: 900; letter-spacing: 0; } .built a:nth-child(7) b { font-style: italic; letter-spacing: -.05em; }

/* accelerating rule lines */
.rules { position: relative; height: 150px; margin-top: clamp(70px, 9vw, 130px); }
.rules i { position: absolute; left: 0; right: 0; height: 1px; background: var(--blue-2); transform: scaleX(0); transform-origin: left; transition: transform 1.1s var(--ease); }
.rules.in i { transform: scaleX(1); }
.rules i:nth-child(1) { top: 0; } .rules i:nth-child(2) { top: 8px; transition-delay: .06s; } .rules i:nth-child(3) { top: 24px; transition-delay: .12s; } .rules i:nth-child(4) { top: 56px; transition-delay: .18s; } .rules i:nth-child(5) { top: 149px; transition-delay: .24s; }

/* CTA + sphere of proofs */
.cta-grid { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr); gap: clamp(28px, 6vw, 110px); align-items: start; padding-top: 22px; }
.cta-grid p { color: var(--ink-2); line-height: 1.25; max-width: 30em; margin-bottom: 14px; }
.proofs { position: relative; height: clamp(520px, 62vw, 800px); margin-top: 30px; overflow: hidden; }
.proofs canvas { position: absolute; left: 50%; top: 150px; width: min(1180px, 104vw); aspect-ratio: 1; transform: translateX(-50%); }
.proofs svg.leaders { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; overflow: visible; }
.proofs svg.leaders path { fill: none; stroke: var(--red); stroke-width: 1; stroke-dasharray: 1; stroke-dashoffset: 1; transition: stroke-dashoffset 1.1s var(--ease) .3s; }
.proofs.in svg.leaders path { stroke-dashoffset: 0; }
.statbox { position: absolute; z-index: 2; min-width: 200px; padding: 12px 18px 10px; border: 1px solid var(--line-2); background: var(--paper); }
.statbox .v { font-size: clamp(1.9rem, 3vw, 2.6rem); font-weight: 400; letter-spacing: -.04em; line-height: 1; font-variant-numeric: tabular-nums; white-space: nowrap; }
.statbox .v small { font-size: .5em; color: var(--mid); letter-spacing: -.02em; }
.statbox p { margin-top: 6px; max-width: 24ch; font-size: .8rem; line-height: 1.2; color: var(--mid); }
.sb1 { left: 5%; top: 44px; } .sb2 { right: 5%; top: 44px; } .sb3 { left: 13%; top: 196px; } .sb4 { right: 13%; top: 196px; }
.proofs-cap { position: absolute; left: 50%; bottom: 14px; z-index: 2; transform: translateX(-50%); display: flex; flex-wrap: wrap; justify-content: center; gap: 4px 18px; padding: 7px 12px 6px; background: var(--paper); border: 1px solid var(--line-2); font-family: var(--dot); font-weight: 800; font-size: .74rem; white-space: nowrap; }
.proofs-cap span { display: inline-flex; align-items: center; gap: 7px; }
.proofs-cap i { flex: none; width: 8px; height: 8px; border-radius: 50%; background: var(--ink); font-style: normal; }
.proofs-cap i.k-gold { width: 10px; height: 10px; background: var(--yellow); outline: 1px solid var(--ink); }
.proofs-cap i.k-x, .proofs-cap i.k-xb { width: auto; height: auto; background: none; border-radius: 0; font-family: var(--sans); font-weight: 600; font-size: 1.15rem; line-height: .6; color: var(--red); }
.proofs-cap i.k-x::before, .proofs-cap i.k-xb::before { content: "×"; } .proofs-cap i.k-xb { color: var(--blue); }

.mini-stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--ink); }
.mini { padding: 18px 20px 22px 0; border-right: 1px solid var(--line); } .mini + .mini { padding-left: 20px; } .mini:last-child { border-right: 0; }
.mini .v { font-size: clamp(2.2rem, 4vw, 3.3rem); font-weight: 400; line-height: .95; letter-spacing: -.05em; font-variant-numeric: tabular-nums; }
.mini .v small { font-family: var(--dot); font-weight: 900; font-size: .4em; letter-spacing: 0; margin-left: .2em; }
.mini .v.d { font-family: var(--dot); font-weight: 900; letter-spacing: -.02em; }
.mini h3 { margin-top: 12px; font-size: 1rem; font-weight: 500; }
.mini p { margin-top: 4px; color: var(--mid); font-size: .86rem; line-height: 1.28; }
.src { display: inline-block; margin-top: 8px; font-family: var(--dot); font-weight: 800; font-size: .7rem; color: var(--mid); border-bottom: 1px solid var(--line-2); } .src:hover { color: var(--blue); border-color: var(--blue); }

/* lab log */
.entries { list-style: none; border-top: 1px solid var(--ink); }
.entry { position: relative; display: grid; grid-template-columns: 92px 1fr; gap: 6px 18px; padding: 20px 0 22px; border-bottom: 1px solid var(--line); transition: background .3s, padding .4s var(--ease); }
.entry:hover { background: var(--paper-2); padding-left: 12px; padding-right: 12px; }
.entry .id { font-family: var(--dot); font-weight: 900; font-size: 1.25rem; line-height: 1; display: flex; align-items: flex-start; gap: 8px; }
.entry .id::before { content: ""; flex: none; width: 10px; height: 10px; margin-top: 4px; background: var(--mid); }
.entry.a .id::before { background: var(--blue); } .entry.c .id::before { background: var(--yellow); border-radius: 50%; outline: 1px solid var(--ink); } .entry.m .id::before { background: var(--red); transform: rotate(45deg); } .entry.next .id::before { background: transparent; border: 1px dashed var(--ink); }
.entry .meta { font-family: var(--dot); font-weight: 800; font-size: .72rem; color: var(--mid); margin-bottom: 6px; }
.entry h3 { font-size: 1.15rem; font-weight: 500; }
.entry p { margin-top: 6px; color: var(--ink-2); font-size: .95rem; line-height: 1.32; max-width: 60ch; }
.entry p b { font-weight: 500; background: linear-gradient(transparent 62%, var(--yellow) 0); }
.entry .link { margin-top: 10px; font-size: .86rem; }
.legend { display: flex; flex-wrap: wrap; gap: 8px 18px; margin-top: 22px; font-family: var(--dot); font-weight: 800; font-size: .72rem; color: var(--ink-2); }
.legend span { display: inline-flex; align-items: center; gap: 7px; } .legend i { width: 9px; height: 9px; }
.lg-a { background: var(--blue); } .lg-c { background: var(--yellow); border-radius: 50%; outline: 1px solid var(--ink); } .lg-m { background: var(--red); transform: rotate(45deg); } .lg-n { border: 1px dashed var(--ink); }

/* limits */
.lim { list-style: none; border-top: 1px solid var(--ink); }
.lim li { display: grid; grid-template-columns: 34px 1fr; gap: 8px; padding: 16px 0; border-bottom: 1px solid var(--line); }
.lim li::before { content: "×"; font-family: var(--dot); font-weight: 900; font-size: 1.5rem; line-height: .9; color: var(--red); }
.lim b { display: block; font-weight: 500; font-size: 1.02rem; margin-bottom: 3px; }
.lim span { color: var(--ink-2); font-size: .94rem; line-height: 1.32; }

/* research (news) */
.news-head { font-family: var(--serif); font-weight: 500; font-size: clamp(2rem, 3.4vw, 2.9rem); letter-spacing: -.02em; line-height: 1; margin-bottom: 34px; }
.news { display: grid; grid-template-columns: minmax(0, 1.18fr) minmax(0, .82fr); gap: 30px; }
.post { position: relative; display: block; }
.post .cover { position: relative; aspect-ratio: 16 / 9.4; overflow: hidden; background: var(--ink); }
.post .cover svg { position: absolute; inset: 0; width: 100%; height: 100%; transition: transform .8s var(--ease); }
.post:hover .cover svg { transform: scale(1.035); }
.post .tab { position: relative; display: inline-block; transform: none; margin-bottom: 8px; border-bottom: 1px solid var(--line-2); }
.post h3 { margin-top: 16px; font-size: clamp(1.25rem, 2vw, 1.75rem); font-weight: 500; letter-spacing: -.03em; line-height: 1.05; transition: color .2s; }
.post:hover h3 { color: var(--blue); }
.post .by { margin-top: 10px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; font-family: var(--dot); font-weight: 800; font-size: .74rem; color: var(--ink-2); }
.post .by i { width: 7px; height: 7px; border-radius: 50%; background: var(--ink); }
.post > p { margin-top: 12px; max-width: 46ch; color: var(--ink-2); font-size: .95rem; line-height: 1.28; }
.news-side { display: grid; gap: 30px; align-content: start; }
.news-side .post h3 { font-size: clamp(1.1rem, 1.5vw, 1.3rem); }

/* contact */
.channels { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.channel { position: relative; display: flex; flex-direction: column; justify-content: space-between; min-height: 150px; padding: 16px; border: 1px solid var(--line-2); overflow: hidden; isolation: isolate; transition: color .3s, border-color .3s; }
.channel::before { content: ""; position: absolute; inset: 0; z-index: -1; background: var(--ink); transform: translateY(101%); transition: transform .45s var(--ease); }
.channel:nth-child(2)::before { background: var(--blue); } .channel:nth-child(3)::before { background: var(--red); } .channel:nth-child(4)::before { background: var(--yellow); }
.channel:hover::before { transform: none; } .channel:hover { color: #fff; border-color: transparent; } .channel:nth-child(4):hover { color: var(--ink); }
.channel svg { width: 22px; height: 22px; }
.channel small { display: block; font-family: var(--dot); font-weight: 800; font-size: .72rem; opacity: .7; }
.channel strong { display: block; font-size: 1.15rem; font-weight: 500; letter-spacing: -.02em; }

/* footer */
.footer { margin-top: clamp(90px, 11vw, 160px); background: var(--blue-soft); overflow: hidden; }
.footer-bars { height: 26px; background: linear-gradient(var(--blue-2) 0 4px, var(--paper) 4px 9px, var(--blue-2) 9px 16px, var(--paper) 16px 19px, var(--blue-2) 19px 26px); }
.footer-top { display: grid; grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, .55fr)); gap: 36px; padding-top: 56px; padding-bottom: 40px; }
.footer-top p { margin-top: 12px; max-width: 30ch; color: var(--ink-2); font-size: .95rem; line-height: 1.25; }
.footer h4 { font-family: var(--dot); font-weight: 800; font-size: .74rem; letter-spacing: .01em; color: var(--ink-2); margin-bottom: 16px; }
.footer ul { list-style: none; display: grid; gap: 9px; }
.footer ul a { font-size: .93rem; font-weight: 500; transition: color .2s; } .footer ul a:hover { color: var(--blue); }
.socials { display: flex; gap: 8px; margin-top: 22px; }
.socials a { width: 38px; height: 38px; display: grid; place-items: center; border: 1px solid var(--ink); transition: background .2s, color .2s; }
.socials a:hover { background: var(--ink); color: #fff; } .socials svg { width: 15px; height: 15px; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px 28px; padding-top: 18px; padding-bottom: 18px; border-top: 1px solid var(--blue-2); font-family: var(--dot); font-weight: 800; font-size: .72rem; color: var(--ink-2); }
.footer-bottom:last-child { padding-bottom: 34px; }   /* the home page footer ends here */
.credits { padding-bottom: 38px; color: var(--mid); font-size: .76rem; line-height: 1.45; max-width: 110ch; }

/* ───────────── inner pages */
.page-head { position: relative; padding: calc(var(--nav-h) + clamp(44px, 7vw, 96px)) 0 clamp(34px, 5vw, 60px); border-bottom: 1px solid var(--ink); overflow: hidden; }
.page-head .lbl-tab { display: inline-block; padding: 6px 9px 5px; border: 1px solid var(--line-2); background: var(--paper-2); font-family: var(--dot); font-weight: 800; font-size: .76rem; line-height: 1; }
.page-head h1 { margin: 18px 0 16px; max-width: 16ch; font-size: clamp(2.5rem, 6vw, 5rem); letter-spacing: -.04em; line-height: .96; }
.page-head h1 em { font-family: var(--serif); font-style: italic; font-weight: 500; font-size: 1.08em; letter-spacing: -.02em; }
.page-head .lede { max-width: 40em; font-family: var(--serif); font-weight: 500; font-size: clamp(1.3rem, 2.1vw, 1.75rem); line-height: 1.12; letter-spacing: -.012em; }
.page-head .byline { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 14px; margin-top: 24px; font-family: var(--dot); font-weight: 800; font-size: .76rem; color: var(--ink-2); }
.page-head .byline i { width: 7px; height: 7px; border-radius: 50%; background: var(--ink); }
.page-head .byline a { border-bottom: 1px solid var(--ink); } .page-head .byline a:hover { color: var(--blue); border-color: var(--blue); }
.page-art { position: absolute; right: var(--gutter); bottom: 0; width: min(34vw, 430px); aspect-ratio: 1 / .8; }
.page-art svg { width: 100%; height: 100%; }
.article-grid { display: grid; grid-template-columns: 210px minmax(0, 740px); gap: clamp(28px, 6vw, 96px); padding-top: clamp(36px, 5vw, 64px); }
.toc { position: sticky; top: calc(var(--nav-h) + 30px); align-self: start; }
.toc p { font-family: var(--dot); font-weight: 800; font-size: .74rem; color: var(--mid); margin-bottom: 12px; }
.toc a { display: block; padding: 6px 0 6px 12px; border-left: 2px solid var(--line); font-size: .88rem; font-weight: 500; line-height: 1.2; color: var(--ink-2); transition: color .2s, border-color .2s; }
.toc a:hover { color: var(--ink); border-color: var(--red); }
.article { min-width: 0; font-size: 1.06rem; line-height: 1.55; letter-spacing: -.012em; color: var(--ink-2); }
.article > * + * { margin-top: 1.1em; }
.article h2 { margin-top: 2.1em; color: var(--ink); font-size: clamp(1.5rem, 2.5vw, 2rem); letter-spacing: -.03em; line-height: 1.06; scroll-margin-top: calc(var(--nav-h) + 24px); }
.article h2:first-child { margin-top: 0; }
.article strong, .article b { color: var(--ink); font-weight: 500; }
.article a:not(.btn):not(.link) { color: var(--ink); border-bottom: 1px solid var(--blue); transition: color .2s, background .2s; }
.article a:not(.btn):not(.link):hover { color: var(--blue); background: var(--blue-soft); }
.article ul, .article ol { padding-left: 1.15em; display: grid; gap: .5em; } .article ul ul { margin-top: .5em; }
.article li::marker { color: var(--red); }
.article .intro { font-family: var(--serif); font-weight: 500; font-size: clamp(1.5rem, 2.5vw, 2rem); line-height: 1.1; letter-spacing: -.015em; color: var(--ink); }
.article blockquote { padding: 18px 20px; background: var(--yellow); color: var(--ink); font-family: var(--serif); font-weight: 500; font-size: 1.3rem; line-height: 1.15; }
.table-wrap { overflow-x: auto; border: 1px solid var(--ink); }
.article table { width: 100%; min-width: 520px; border-collapse: collapse; font-size: .9rem; line-height: 1.35; }
.article th { text-align: left; font-family: var(--dot); font-weight: 800; font-size: .74rem; color: var(--ink); background: var(--paper-2); }
.article th, .article td { padding: 11px 13px; border-bottom: 1px solid var(--line); vertical-align: top; }
.article tr:last-child td { border-bottom: 0; } .article td:first-child { color: var(--ink); }
.article-end { margin-top: 2.6em; padding-top: 1.8em; border-top: 1px solid var(--ink); display: flex; flex-wrap: wrap; gap: 8px; }
.fineprint { margin-top: 2em; color: var(--mid); font-size: .8rem; line-height: 1.45; }
.legal { max-width: 740px; padding-top: clamp(36px, 5vw, 64px); }
.cards3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 30px 24px; }
.nf { min-height: 82vh; display: grid; place-items: center; text-align: center; padding: calc(var(--nav-h) + 30px) var(--gutter) 30px; }
.nf .big { font-family: var(--dot); font-weight: 900; font-size: clamp(7rem, 30vw, 20rem); line-height: .8; letter-spacing: -.04em; }
.nf .big i { font-style: normal; color: var(--red); }
.nf h1 { margin: 22px 0 10px; font-family: var(--serif); font-weight: 500; font-size: clamp(1.8rem, 4vw, 3rem); }
.nf p { color: var(--ink-2); margin-bottom: 22px; }

/* ───────────── art animation helpers (thick-line illustrations) */
.s-ink { stroke: var(--ink); } .s-blue { stroke: var(--blue); } .s-red { stroke: var(--red); } .s-yel { stroke: var(--yellow); } .s-lite { stroke: var(--blue-2); }
.f-ink { fill: var(--ink); } .f-blue { fill: var(--blue); } .f-red { fill: var(--red); } .f-yel { fill: var(--yellow); } .f-paper { fill: var(--paper); } .f-soft { fill: var(--blue-soft); }
.art-t { font-family: var(--dot); font-weight: 900; }
.spin { transform-box: fill-box; transform-origin: center; animation: spin 9s linear infinite; } .spin.rev { animation-direction: reverse; animation-duration: 14s; } .spin.fast { animation-duration: 2.4s; }
@keyframes spin { to { transform: rotate(360deg); } }
.pulse { animation: pulse 2.2s ease-in-out infinite; } @keyframes pulse { 0%, 100% { opacity: .25; } 50% { opacity: 1; } }
.dash { stroke-dasharray: 6 8; animation: dash 1.2s linear infinite; } @keyframes dash { to { stroke-dashoffset: -28; } }
.flip-a { animation: flipA 4.4s steps(1) infinite; } .flip-b { animation: flipB 4.4s steps(1) infinite; }
@keyframes flipA { 0% { opacity: 1; } 50% { opacity: 0; } } @keyframes flipB { 0% { opacity: 0; } 50% { opacity: 1; } }
.bob { animation: bob 3.2s ease-in-out infinite; } @keyframes bob { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-7px); } }
.slide { animation: slide 3.4s var(--ease-io) infinite; } @keyframes slide { 0%, 8% { transform: translateX(0); opacity: 0; } 14% { opacity: 1; } 62% { transform: translateX(118px); opacity: 1; } 70%, 100% { transform: translateX(118px); opacity: 0; } }
.pop { transform-box: fill-box; transform-origin: center; animation: pop 3.4s var(--ease) infinite; } @keyframes pop { 0%, 62% { transform: scale(0) rotate(-20deg); } 70%, 94% { transform: scale(1) rotate(-8deg); } 100% { transform: scale(0); } }
.seq { animation: seq 4s steps(1) infinite; } .seq.d1 { animation-delay: 1s; } .seq.d2 { animation-delay: 2s; } .seq.d3 { animation-delay: 3s; }
@keyframes seq { 0% { fill: var(--yellow); } 25%, 100% { fill: transparent; } }
.grow { transform-box: fill-box; transform-origin: left; animation: grow 3.6s var(--ease-io) infinite; } .grow.d1 { animation-delay: .25s; } .grow.d2 { animation-delay: .5s; } .grow.d3 { animation-delay: .75s; }
@keyframes grow { 0%, 5% { transform: scaleX(0); } 45%, 88% { transform: scaleX(1); } 100% { transform: scaleX(0); } }
.blink { animation: blink 1s steps(1) infinite; } @keyframes blink { 50% { opacity: 0; } }

/* ───────────── reveal */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .8s var(--ease), transform .8s var(--ease); transition-delay: var(--d, 0ms); }
.reveal.in { opacity: 1; transform: none; }
.no-js .reveal, .no-js .hero-after { opacity: 1; transform: none; }
.no-js .rules i { transform: none; } .no-js .statement-grid .t-statement .w { color: var(--ink); }
/* without scripts: every level is laid out open, and the receipts show their finished state */
.no-js .levels { flex-direction: column; height: auto; } .no-js .level { flex: none; } .no-js .level-closed { display: none; }
.no-js .level-open { position: relative; width: auto; opacity: 1; pointer-events: auto; } .no-js .level-chip { opacity: 1; }
.no-js .receipt-line { opacity: 1; transform: none; } .no-js .stamp { opacity: 1; transform: rotate(-9deg); }
.no-js .big-stamp { opacity: 1; transform: rotate(-8deg); } .no-js .hl::before { transform: scaleX(1); }
.no-js .proofs svg.leaders path { stroke-dashoffset: 0; }

/* ───────────── responsive */
@media (max-width: 1100px) {
  .principles { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 26px 16px; }
  .uc-track { grid-auto-columns: calc((100% - 2 * 20px) / 2.3); }
  .footer-top { grid-template-columns: repeat(3, minmax(0, 1fr)); } .footer-top > :first-child { grid-column: 1 / -1; }
  .sb3 { left: 5%; } .sb4 { right: 5%; }
  .cards3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 940px) {
  .nav .wrap { grid-template-columns: 1fr auto; } .nav nav, .nav-right .btn { display: none; } .nav-toggle { display: inline-flex; }
  .hero-grid { grid-template-columns: 1fr; min-height: 0; gap: 10px; padding-top: 26px; }
  .stack { justify-self: center; max-width: 520px; margin: 10px auto 0; }
  .split, .statement-grid, .lab, .cta-grid, .news { grid-template-columns: 1fr; } .split .sticky { position: static; }
  .levels { flex-direction: column; height: auto; }
  .level { flex: none !important; min-height: 64px; transition: min-height .5s var(--ease), background .4s, border-color .3s; } .level.open { min-height: 0; }
  .level-closed { position: relative; flex-direction: row; align-items: center; justify-content: flex-start; gap: 16px; padding: 14px 16px; } .level-closed span { writing-mode: horizontal-tb; transform: none; align-self: center; }
  .level.open .level-closed { display: none; }
  .level-open { position: relative; width: auto; display: none; grid-template-columns: 1fr; padding: 18px 16px 20px; } .level.open .level-open { display: grid; }
  .level-open .num { grid-row: auto; font-size: 5.4rem; } .level-open dl { grid-template-columns: 1fr; gap: 12px; }
  .built { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .proofs { height: auto; overflow: visible; display: grid; grid-template-columns: 1fr 1fr; gap: 36px 10px; margin-top: 26px; padding-top: 26px; }
  .statbox .tab { white-space: normal; max-width: calc(100% + 2px); line-height: 1.1; }
  .proofs canvas { position: relative; left: auto; top: auto; transform: none; grid-column: 1 / -1; width: 100%; order: 5; } .proofs svg.leaders { display: none; }
  .statbox { position: relative; inset: auto !important; min-width: 0; } .proofs-cap { position: relative; left: auto; bottom: auto; transform: none; grid-column: 1 / -1; order: 6; justify-self: center; white-space: normal; text-align: center; }
  .mini-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); } .mini:nth-child(2) { border-right: 0; } .mini:nth-child(-n+2) { border-bottom: 1px solid var(--line); } .mini:nth-child(3) { padding-left: 0; }
  .channels { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .article-grid { grid-template-columns: 1fr; } .toc { display: none; } .page-art { display: none; }
}
@media (max-width: 620px) {
  .feature-cards, .principles, .attacks, .cards3 { grid-template-columns: 1fr; }
  .graded-row { grid-template-columns: 1fr; gap: 6px; padding: 12px 14px; min-height: 0; } .graded-key { padding: 12px 14px 11px; }
  .uc-track { grid-auto-columns: 82%; }
  .tech-row { grid-template-columns: 1fr 16px; } .tech-row p { grid-column: 1 / -1; grid-row: 2; }
  .entry { grid-template-columns: 1fr; } .entry:hover { padding-left: 0; padding-right: 0; }
  .statbox { padding: 10px 12px 9px; } .statbox .v { font-size: 1.7rem; }
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stack { aspect-ratio: 1 / 1.1; margin-bottom: 18px; } .stack-main { inset: 5% 0 25% 0; }
  .receipt { width: 60%; min-width: 0; padding-bottom: 40px; } .receipt-note { display: none; } .stack-verify { width: 38%; min-width: 0; }
  .hero-cta .btn { flex: 1 1 auto; justify-content: center; }
  .section-head { align-items: flex-start; flex-direction: column; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  /* no animation at all: every illustration rests in its finished, readable state */
  *, *::before, *::after { animation: none !important; transition-duration: .001ms !important; transition-delay: 0s !important; }
  .splash { display: none; } .flip-b { opacity: 0; } .js-type .hero h1 { visibility: visible; }
  .reveal, .hero-after { opacity: 1; transform: none; }
}
@media print { .nav, .mobile-menu, .ticker, .stack, .splash { display: none !important; } }