:root { --ink:#15181f; --paper:#f3f1eb; --white:#fbfaf7; --muted:#686c73; --line:#d6d3ca; --blue:#3c55db; --blue-dark:#2236a3; --lime:#d6f06d; --shadow:0 24px 80px rgba(25,30,50,.12); font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif; color:var(--ink); background:var(--paper); font-synthesis:none; }
* { box-sizing:border-box; }
html { scroll-behavior:smooth; }
body { margin:0; min-width:320px; }
a { color:inherit; text-decoration:none; }
button,input { font:inherit; }
.site-header { height:78px; display:flex; align-items:center; justify-content:space-between; padding:0 clamp(24px,5vw,72px); border-bottom:1px solid var(--line); position:sticky; top:0; z-index:10; background:color-mix(in srgb,var(--paper) 92%,transparent); backdrop-filter:blur(16px); }
.wordmark { display:flex; align-items:baseline; gap:10px; letter-spacing:-.05em; }.wordmark span{font-size:24px;font-weight:800}.wordmark small{font-family:'DM Mono',monospace;font-size:10px;letter-spacing:.08em;color:var(--muted)}
nav { display:flex; gap:28px; align-items:center; font-size:13px; font-weight:600; } nav a:hover{color:var(--blue)}.nav-paper{padding:10px 14px;border:1px solid var(--ink);border-radius:999px}
main>section { padding:100px clamp(24px,7vw,110px); }
.hero { min-height:700px; display:grid; grid-template-columns:1.05fr .95fr; align-items:center; gap:6vw; overflow:hidden; }
.eyebrow,.section-index { font-family:'DM Mono',monospace; font-size:11px; letter-spacing:.12em; text-transform:uppercase; color:var(--blue); }
h1,h2,h3,p { margin-top:0; }.hero h1{font-size:clamp(52px,6.5vw,96px);line-height:.93;letter-spacing:-.065em;margin:22px 0 30px;max-width:850px}.hero h1 em{font-family:Newsreader,serif;font-weight:500;color:var(--blue)}
.lede { max-width:660px; font-size:clamp(17px,1.4vw,21px); line-height:1.65; color:#535760; }
.scope-note{max-width:680px;display:grid;grid-template-columns:130px 1fr;gap:18px;margin:27px 0 0;padding:17px 19px;border-left:3px solid var(--blue);background:rgba(60,85,219,.07)}.scope-note>span{padding-top:2px;font-family:'DM Mono',monospace;font-size:9px;line-height:1.5;letter-spacing:.1em;text-transform:uppercase;color:var(--blue)}.scope-note p{margin:0;font-size:12px;line-height:1.65;color:#5d6169}.scope-note strong{color:var(--ink)}
.hero-actions { display:flex; gap:12px; flex-wrap:wrap; margin:24px 0 20px; }.button{display:inline-flex;align-items:center;justify-content:center;padding:14px 20px;border-radius:6px;border:1px solid var(--ink);font-size:13px;font-weight:700;cursor:pointer;transition:.18s ease;background:none}.button:hover{transform:translateY(-2px);box-shadow:0 8px 24px rgba(20,23,30,.12)}.button.primary{background:var(--ink);color:white}.button.secondary{background:transparent;color:var(--ink)}.button:disabled{opacity:.42;cursor:not-allowed;transform:none;box-shadow:none}
.local-note{font-family:'DM Mono',monospace;font-size:11px;color:var(--muted);display:flex;align-items:center;gap:8px}.local-note span{width:7px;height:7px;background:#52a066;border-radius:50%}
.hero-visual{height:500px;position:relative;}.visual-card{position:absolute;width:min(65%,350px);padding:10px 10px 15px;background:var(--white);box-shadow:var(--shadow);border-radius:6px;transform:rotate(-4deg);}.visual-card span{display:block;font-family:'DM Mono',monospace;font-size:10px;color:var(--muted);padding:9px 4px 0}.original-card{left:0;top:20px}.encrypted-card{right:-3%;bottom:18px;transform:rotate(5deg)}.demo-scene{display:block;width:100%;height:auto;aspect-ratio:4/3;object-fit:cover;background:#20252f}.encrypted-card.is-pending .demo-scene{opacity:.18}.visual-arrow{position:absolute;left:46%;top:44%;z-index:2;background:var(--lime);width:50px;height:50px;border-radius:50%;display:grid;place-items:center;font-size:26px}.thumbnail-chip{position:absolute;left:3%;bottom:5px;z-index:3;background:var(--ink);color:white;padding:10px;display:grid;grid-template-columns:64px 24px 1fr;align-items:center;gap:8px;border-radius:5px;box-shadow:var(--shadow);font-size:11px;overflow:hidden}.thumbnail-chip .demo-scene{width:64px;height:48px;image-rendering:pixelated}.thumbnail-chip strong{color:var(--lime);font-size:22px}
.intro-section{background:var(--ink);color:white}.intro-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:10vw}.intro-grid h2,.section-heading h2,.method-heading h2,.paper-section h2{font-size:clamp(34px,4.2vw,64px);line-height:1.04;letter-spacing:-.045em}.intro-grid p{font-size:17px;line-height:1.75;color:#b8bac1}.intro-grid h2{margin:0}
.demo-section{background:#e7e5df}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:40px;margin-bottom:42px}.section-heading h2{margin:10px 0 0}.section-heading>p{max-width:390px;color:var(--muted);line-height:1.6}.demo-hint{display:block;width:max-content;margin-bottom:7px;padding:4px 7px;border:1px solid color-mix(in srgb,var(--blue) 28%,transparent);border-radius:3px;color:var(--blue);font-family:'DM Mono',monospace;font-size:9px;letter-spacing:.08em;text-transform:uppercase}.demo-shell{background:var(--white);box-shadow:var(--shadow);border:1px solid #ddd9cf}.demo-controls{padding:24px;display:grid;grid-template-columns:1.2fr 1.1fr 1.35fr .7fr auto auto;gap:16px;align-items:end;border-bottom:1px solid var(--line)}.demo-controls>label{display:grid;gap:8px}.demo-controls label>span,.upload-control>span{font-family:'DM Mono',monospace;font-size:10px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}.upload-control{border:1px dashed #aaa69d;padding:10px 12px;border-radius:5px;cursor:pointer}.upload-control strong{font-size:13px}.upload-control small{font-size:10px;color:var(--muted)}#image-input{position:absolute;opacity:0;pointer-events:none}.demo-controls input[type=password]{height:46px;border:1px solid var(--line);background:white;border-radius:5px;padding:0 12px;min-width:0}.demo-controls input[type=range]{accent-color:var(--blue)}.demo-controls output{float:right;color:var(--ink)}.block-control{margin:-8px;padding:12px;border:2px solid var(--blue);border-radius:7px;background:color-mix(in srgb,var(--blue) 7%,white);box-shadow:0 0 0 5px color-mix(in srgb,var(--blue) 5%,transparent)}.block-control>span em{display:inline-block;margin-left:5px;padding:3px 5px;border-radius:3px;background:var(--lime);color:var(--ink);font-family:Inter,sans-serif;font-size:8px;font-style:normal;font-weight:800;letter-spacing:.04em}.block-control input[type=range]{width:100%;cursor:ew-resize}.range-legend{display:flex;justify-content:space-between;color:var(--muted);font-size:8px}.block-control>strong{font-size:10px;line-height:1.35;color:var(--blue)}.demo-run{height:46px;white-space:nowrap}.status-row{grid-column:1/-1;display:flex;align-items:center;gap:8px;font-family:'DM Mono',monospace;font-size:10px;color:var(--muted)}.status-row strong{margin-left:auto;color:var(--ink)}.status-dot{width:7px;height:7px;background:#52a066;border-radius:50%}.status-row.busy .status-dot{background:#e7a62d;animation:pulse 1s infinite}@keyframes pulse{50%{opacity:.25}}
.demo-scope{display:grid;grid-template-columns:180px 1fr;gap:24px;align-items:start;margin-bottom:14px;padding:16px 24px;border:1px solid color-mix(in srgb,var(--blue) 18%,var(--line));background:color-mix(in srgb,var(--blue) 6%,var(--white));}.demo-scope strong{font-family:'DM Mono',monospace;font-size:9px;line-height:1.5;letter-spacing:.09em;text-transform:uppercase;color:var(--blue)}.demo-scope p{margin:0;max-width:980px;font-size:11px;line-height:1.6;color:#5d6169}
.canvas-grid{display:grid;grid-template-columns:1fr 1fr;gap:1px;background:var(--line)}.canvas-grid figure{margin:0;background:#ece9e1;padding:22px}.canvas-wrap{position:relative;aspect-ratio:4/3;background:#d9d7d0;display:grid;place-items:center;overflow:hidden}.canvas-wrap canvas{width:100%;height:100%;object-fit:contain}.canvas-badge{position:absolute;left:12px;top:12px;background:rgba(15,18,24,.82);color:white;padding:6px 8px;border-radius:3px;font-family:'DM Mono',monospace;font-size:9px;text-transform:uppercase}.canvas-badge.accent{background:var(--blue)}figcaption{font-size:12px;margin-top:10px;color:var(--muted)}.asset-credit{float:right;font-family:'DM Mono',monospace;font-size:8px}.asset-credit a{text-decoration:underline;text-underline-offset:2px}.asset-credit a:hover{color:var(--blue)}
.thumbnail-proof{position:relative;display:grid;grid-template-columns:minmax(220px,.8fr) auto minmax(230px,.7fr);gap:clamp(28px,4vw,64px);align-items:center;padding:34px 38px;overflow:hidden;background:var(--ink);color:white;border-top:1px solid #2b303b}.thumbnail-proof:before{content:'';position:absolute;inset:-80% 15% -80% 42%;background:radial-gradient(circle,rgba(214,240,109,.13),transparent 58%);pointer-events:none}.proof-intro{position:relative;display:grid;gap:9px}.proof-intro>span{font-family:'DM Mono',monospace;font-size:9px;letter-spacing:.13em;text-transform:uppercase;color:var(--lime)}.proof-intro>strong{font-size:clamp(18px,1.55vw,23px);line-height:1.25;letter-spacing:-.025em}.thumbnail-comparison{position:relative;display:flex;align-items:center;gap:20px}.thumbnail-item{position:relative;display:grid;gap:8px}.thumbnail-item p{margin:0;font-family:'DM Mono',monospace;text-transform:uppercase;font-size:8px;letter-spacing:.07em;color:#999da8}.thumbnail-item canvas{width:96px;height:72px;object-fit:fill;image-rendering:pixelated;border:1px solid #565c68;background:#252a34}.proof-equation{width:43px;height:43px;display:grid;place-items:center;border-radius:50%;background:var(--lime);color:var(--ink);box-shadow:0 0 0 7px rgba(214,240,109,.08)}.proof-equation strong{font-size:22px;line-height:1}.proof-equation small{position:absolute;margin-top:68px;font-family:'DM Mono',monospace;font-size:7px;letter-spacing:.12em;text-transform:uppercase;color:#8f949f}.result-thumbnail canvas{border:2px solid var(--lime);box-shadow:0 0 0 5px rgba(214,240,109,.09),0 0 28px rgba(214,240,109,.08)}.preserved-badge{position:absolute;right:-9px;bottom:-8px;padding:5px 7px;background:var(--lime);color:var(--ink);border-radius:2px;font-family:'DM Mono',monospace;font-size:7px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;opacity:.42;transform:translateY(3px);transition:opacity .25s ease,transform .25s ease}.proof-copy{position:relative;display:grid;gap:7px;margin:0;padding-left:24px;border-left:1px solid #383e49;font-size:12px}.proof-copy strong{font-size:14px;color:white}.proof-copy span{color:#9da2ad;line-height:1.5}.thumbnail-proof.is-verified .preserved-badge,.thumbnail-proof.is-roundtrip .preserved-badge{opacity:1;transform:translateY(0)}.thumbnail-proof.is-verified .result-thumbnail:after,.thumbnail-proof.is-roundtrip .result-thumbnail:after{content:'';position:absolute;inset:14px -10px -10px -10px;border:1px solid var(--lime);opacity:0;animation:thumbnail-ping 1.25s ease-out 1}.thumbnail-proof.is-verified .proof-copy strong,.thumbnail-proof.is-roundtrip .proof-copy strong{color:var(--lime)}@keyframes thumbnail-ping{0%{opacity:.8;transform:scale(.82)}100%{opacity:0;transform:scale(1.24)}}
.method-section{background:var(--paper)}.method-heading{display:grid;grid-template-columns:1fr .65fr;gap:10vw;align-items:end;margin:24px 0 68px}.method-heading h2{margin:0}.method-heading p{line-height:1.7;color:var(--muted)}.method-steps{padding:0;margin:0;list-style:none;display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.method-steps li{padding:28px 24px 34px;border-right:1px solid var(--line)}.method-steps li:last-child{border-right:0}.method-steps li>span{font-family:'DM Mono';font-size:10px;color:var(--blue)}.method-steps h3{font-size:21px;margin:20px 0 10px}.method-steps p{font-size:13px;line-height:1.65;color:var(--muted)}.method-icon{height:76px;margin-top:25px;position:relative}.grid-icon{background:linear-gradient(90deg,transparent 32%,var(--line) 33% 34%,transparent 35% 65%,var(--line) 66% 67%,transparent 68%),linear-gradient(transparent 32%,var(--line) 33% 34%,transparent 35% 65%,var(--line) 66% 67%,transparent 68%);border:1px solid var(--ink);width:76px}.pair-icon:before,.pair-icon:after{content:'';position:absolute;width:48px;height:48px;border:1px solid var(--ink);top:14px}.pair-icon:before{left:0;background:#bdc6f9}.pair-icon:after{left:54px;background:var(--lime)}.shuffle-icon{background:repeating-linear-gradient(90deg,var(--blue) 0 8px,transparent 8px 15px);width:105px;clip-path:polygon(0 10%,100% 0,100% 28%,0 38%,0 62%,100% 50%,100% 76%,0 100%)}.reverse-icon{width:76px;border:2px solid var(--ink);border-left-color:transparent;border-radius:50%}.reverse-icon:after{content:'↶';font-size:38px;position:absolute;inset:8px;display:grid;place-items:center;color:var(--blue)}.invariant{position:relative;display:grid;grid-template-columns:minmax(150px,.55fr) minmax(320px,1.25fr) minmax(230px,.8fr);gap:clamp(28px,4vw,64px);align-items:center;margin-top:38px;padding:30px 34px 30px 40px;overflow:hidden;background:var(--ink);color:white;box-shadow:0 18px 52px rgba(21,24,31,.14)}.invariant:before{content:'';position:absolute;inset:0 auto 0 0;width:7px;background:var(--lime)}.invariant>span{font-family:'DM Mono';font-size:10px;line-height:1.5;letter-spacing:.12em;text-transform:uppercase;color:var(--lime)}.invariant-statement{display:grid;gap:9px}.invariant-statement strong{font-size:clamp(18px,1.7vw,24px);line-height:1.25;letter-spacing:-.02em}.invariant code{font-family:'DM Mono';font-size:13px;color:#bdc6f9}.invariant code sub{font-size:.7em}.invariant p{margin:0;padding-left:24px;border-left:1px solid #3b404a;color:#d9dce3;font-size:14px;line-height:1.55}.invariant p strong{color:white}
.paper-section{background:var(--blue);color:white;display:grid;grid-template-columns:1.2fr .8fr;gap:10vw}.paper-section .section-index{color:var(--lime)}.paper-meta{padding-top:38px}.paper-meta>p{line-height:1.7;color:#dfe2ff}.paper-meta>p:nth-child(2){font-family:'DM Mono';font-size:11px}.paper-meta .button.primary{background:white;color:var(--blue);border-color:white}.paper-meta>div{display:flex;align-items:center;gap:24px;margin-top:28px}.text-link{font-size:12px;text-decoration:underline;text-underline-offset:4px}
footer{padding:34px clamp(24px,7vw,110px);display:grid;grid-template-columns:auto 1fr auto;gap:40px;align-items:center;background:var(--ink);color:white}footer p{margin:0;text-align:center;font-size:11px;color:#9ea1aa}footer>a:last-child{font-size:11px}
@media(max-width:1000px){nav a:not(.nav-paper){display:none}.hero{grid-template-columns:1fr;min-height:auto}.hero-visual{max-width:650px;width:100%;margin:auto}.demo-controls{grid-template-columns:1fr 1fr}.demo-run{width:100%}.thumbnail-proof{grid-template-columns:1fr auto}.proof-copy{grid-column:1/-1;padding:18px 0 0;border-left:0;border-top:1px solid #383e49}.method-steps{grid-template-columns:1fr 1fr}.method-steps li:nth-child(2){border-right:0}.method-steps li:nth-child(-n+2){border-bottom:1px solid var(--line)}.invariant{grid-template-columns:1fr 1.6fr}.invariant p{grid-column:1/-1;padding:18px 0 0;border-left:0;border-top:1px solid #3b404a}}
@media(max-width:700px){main>section{padding:72px 20px}.site-header{padding:0 20px}.hero h1{font-size:50px}.scope-note,.demo-scope{grid-template-columns:1fr;gap:6px}.hero-visual{height:380px}.intro-grid,.method-heading,.paper-section{grid-template-columns:1fr}.section-heading{display:block}.canvas-grid{grid-template-columns:1fr}.demo-controls{grid-template-columns:1fr}.thumbnail-proof{grid-template-columns:1fr;padding:28px 22px}.thumbnail-comparison{justify-content:space-between;gap:12px}.thumbnail-item canvas{width:88px;height:66px}.proof-copy{grid-column:auto}.method-steps{grid-template-columns:1fr}.method-steps li{border-right:0;border-bottom:1px solid var(--line)}.invariant{grid-template-columns:1fr}.paper-section{gap:20px}footer{grid-template-columns:1fr;text-align:center}footer p{text-align:center}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}