:root{color-scheme:light;--paper:#f7f0df;--surface:#fffaf0;--ink:#172126;--muted:#4b5659;--line:#b8ae99;--blue:#075985;--blue-hi:#064b70;--yellow:#f2b134;--red:#b53924;--green:#126a57;--focus:#075985;font-family:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--paper);color:var(--ink)}:root.dark{color-scheme:dark;--paper:#152026;--surface:#1e2a30;--ink:#eef2e6;--muted:#c3ceca;--line:#637176;--blue:#72c7f5;--blue-hi:#a9e1fb;--focus:#f2b134}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;min-width:320px;font-size:16px;line-height:1.55;background:radial-gradient(circle at 1px 1px,color-mix(in srgb,var(--ink) 9%,transparent) 1px,transparent 0) 0 0/7px 7px,var(--paper)}button,input{font:inherit}button,a,input{outline-offset:3px}button:focus-visible,a:focus-visible,input:focus-visible,canvas:focus-visible{outline:3px solid var(--focus)}a{color:inherit;text-underline-offset:3px}.skip-link{position:fixed;top:-60px;left:12px;padding:10px 14px;background:var(--ink);color:var(--paper);z-index:10}.skip-link:focus{top:12px}.topbar,footer{width:min(1180px,calc(100% - 48px));margin:auto;display:flex;align-items:center;justify-content:space-between;gap:20px}.topbar{height:76px;border-bottom:1px solid var(--line)}.brand{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-weight:800;text-decoration:none;letter-spacing:-.04em}.brand-dot{display:inline-grid;place-items:center;width:26px;height:26px;margin-right:7px;background:var(--yellow);color:#172126;border:2px solid var(--ink);box-shadow:3px 3px 0 var(--ink)}nav{display:flex;align-items:center;gap:18px;font-size:.91rem}nav a{font-weight:650}.theme{min-width:44px;min-height:44px;border:1px solid var(--line);background:transparent;color:var(--ink);cursor:pointer}.intro,main>section,footer,.legal{width:min(1180px,calc(100% - 48px));margin-inline:auto}.intro{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(300px,.85fr);gap:clamp(40px,7vw,110px);align-items:center;padding:72px 0 88px}.eyebrow{margin:0 0 8px;text-transform:uppercase;letter-spacing:.115em;font:700 .75rem ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--blue)}h1,h2,h3{line-height:1.1;letter-spacing:-.04em;margin:0;color:var(--ink)}h1{max-width:700px;font-size:clamp(2.35rem,6vw,4.75rem)}h2{font-size:clamp(1.7rem,3vw,2.6rem)}h3{font-size:1.18rem}.lede{max-width:650px;font-size:clamp(1.08rem,2vw,1.27rem);line-height:1.55;color:var(--muted)}.actions{display:flex;align-items:center;flex-wrap:wrap;gap:18px;margin-top:28px}.button{min-height:46px;display:inline-flex;align-items:center;justify-content:center;padding:10px 17px;background:var(--blue);border:2px solid var(--blue);box-shadow:4px 4px 0 var(--ink);color:#fff;text-decoration:none;font-weight:800;cursor:pointer}.button:hover{background:var(--blue-hi)}.button:active{transform:translate(2px,2px);box-shadow:2px 2px 0 var(--ink)}.button[disabled],.text-button[disabled]{opacity:.45;cursor:not-allowed}.secondary{background:var(--surface);color:var(--ink);border-color:var(--ink)}.quiet-link{font-weight:750}.micro{font-size:.83rem;color:var(--muted)}.intro .micro{margin-top:20px}.proof-figure{margin:0}.paper-art{aspect-ratio:1.25;background:var(--surface);border:2px solid var(--ink);box-shadow:11px 11px 0 var(--yellow);position:relative;display:grid;grid-template-columns:repeat(3,1fr);gap:10px;padding:22px;overflow:hidden}.paper-art:before,.paper-art:after{content:"";position:absolute;inset:10px;border:1px solid var(--line);pointer-events:none}.paper-art i{position:absolute;inset:auto -15% 14% 10%;height:22%;background:repeating-radial-gradient(circle,var(--blue) 0 2px,transparent 3px 8px);transform:rotate(-8deg);opacity:.82}.paper-art b{z-index:1;align-self:center;justify-self:center;display:grid;place-items:center;width:74px;aspect-ratio:1;border:3px solid var(--ink);font:800 2.7rem ui-monospace;color:var(--ink)}.paper-art b:nth-of-type(1){background:var(--yellow)}.paper-art b:nth-of-type(2){background:#c5e6f3}.paper-art b:nth-of-type(3){background:#e5a094}.paper-art em{position:absolute;z-index:2;right:22px;bottom:26px;border-radius:50%;width:80px;height:80px;border:8px solid var(--ink);background:radial-gradient(circle at 34% 33%,transparent 0 10px,var(--yellow) 11px 13px,transparent 14px),repeating-radial-gradient(circle,var(--ink) 0 1px,transparent 2px 7px);box-shadow:15px 17px 0 -9px var(--ink)}figcaption{font-size:.84rem;margin-top:15px;color:var(--muted)}.workspace{padding:74px 0;border-top:2px solid var(--ink)}.section-heading{max-width:630px;margin-bottom:30px}.section-heading h2{margin-top:4px}.empty{min-height:360px;display:grid;justify-items:center;align-content:center;text-align:center;padding:40px;border:2px dashed var(--line);background:color-mix(in srgb,var(--surface) 90%,transparent)}.empty p{max-width:500px;color:var(--muted)}.empty-art{display:flex;gap:7px;margin-bottom:18px}.empty-art span{display:grid;place-items:center;width:50px;height:50px;background:var(--yellow);border:2px solid var(--ink);font:800 1.4rem ui-monospace}.empty-art span:nth-child(2){background:#c5e6f3}.empty-art span:nth-child(3){background:#e5a094}.file-button input{position:absolute;width:1px;height:1px;opacity:0}.proof-grid{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:26px}.canvas-panel{min-width:0}.canvas-frame{display:grid;place-items:center;background:#26363b;border:2px solid var(--ink);padding:12px;min-height:360px}.canvas-frame canvas{display:block;max-width:100%;height:auto;cursor:crosshair;background:#fff}.canvas-tools{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-top:13px}.canvas-tools input{position:absolute;width:1px;height:1px;opacity:0}.text-button{min-height:44px;border:0;background:transparent;color:var(--blue);padding:7px 0;text-decoration:underline;text-underline-offset:3px;font-weight:700;cursor:pointer}.mark-panel{background:var(--surface);border-top:4px solid var(--ink);padding:20px}.mark-panel>p{margin-top:8px}.mark{padding:15px 0;border-top:1px solid var(--line);display:grid;grid-template-columns:46px 1fr;gap:8px}.mark label,.license-form label{display:block;font-size:.8rem;font-weight:750;color:var(--muted)}input{width:100%;min-height:42px;margin-top:3px;padding:8px 9px;border:1px solid var(--line);border-radius:0;background:var(--paper);color:var(--ink)}.mark label:nth-of-type(2){grid-column:2}.mark-number{grid-row:span 2;width:44px;height:44px;border:2px solid var(--ink);background:var(--yellow);font:800 .82rem ui-monospace;cursor:pointer}.sample{grid-column:2;display:flex;align-items:center;gap:8px;font-size:.85rem}.sample span{width:20px;height:20px;border:1px solid var(--ink)}code{font:650 .75rem ui-monospace;color:var(--muted)}.remove{margin-left:auto;width:34px;height:34px;border:0;background:transparent;color:var(--red);font-size:1.6rem;cursor:pointer}.selected{background:color-mix(in srgb,var(--yellow) 20%,transparent);margin-inline:-8px;padding-inline:8px}.required{font-size:.7rem;color:var(--red)}.empty-list{color:var(--muted);font-size:.9rem}.mark-panel>.button{width:100%;margin-top:12px}.result{margin-top:20px;padding:15px 0;border-top:2px solid var(--ink)}.result h3{font-size:1.05rem}.result p{font-size:.91rem}.result table{width:100%;border-collapse:collapse;font-size:.77rem}.result caption{text-align:left;font-weight:800;margin-bottom:6px}.result th,.result td{padding:6px 4px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}.exports{display:flex;gap:15px;flex-wrap:wrap;margin-top:15px;border-top:1px solid var(--line)}.method{padding:90px 0}.method h2{margin-top:5px}.method ol{list-style:none;counter-reset:proof;display:grid;grid-template-columns:repeat(3,1fr);gap:24px;padding:0;margin:35px 0}.method li{counter-increment:proof;padding-top:54px;position:relative;color:var(--muted)}.method li:before{content:counter(proof,decimal-leading-zero);position:absolute;top:0;left:0;color:var(--ink);font:800 2rem ui-monospace;border-bottom:5px dotted var(--blue)}.method li strong{color:var(--ink)}.limit{border-left:5px solid var(--yellow);padding-left:16px;max-width:800px}.pro{background:var(--ink);color:#eef2e6;width:100%;padding:50px max(24px,calc((100% - 1180px)/2));display:grid;grid-template-columns:1fr minmax(270px,360px);gap:50px;align-items:center}.pro h2{color:#fff}.pro p{color:#d5ded8}.pro .eyebrow{color:var(--yellow)}.license-form{background:#eef2e6;color:#172126;padding:19px}.license-form .button{width:100%;margin-bottom:14px}.license-form .micro{color:#4b5659}.license-ok{padding:20px;border:2px solid var(--yellow);color:#fff}.legal{max-width:760px;padding:86px 0}.legal .lede{margin-bottom:45px}.legal section{width:auto;margin:26px 0}.legal h2{font-size:1.45rem}.legal .button{margin-top:25px}footer{min-height:92px;border-top:1px solid var(--line);font-size:.78rem;color:var(--muted);padding:20px 0}@media(prefers-reduced-motion:no-preference){.button,.mark,.result{transition:transform .18s ease,opacity .18s ease,background .18s ease}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media(max-width:760px){.topbar,footer,.intro,main>section,.legal{width:min(100% - 32px,1180px)}.topbar{height:64px}.topbar nav a:first-child{display:none}.intro{grid-template-columns:1fr;padding:46px 0 60px;gap:42px}.proof-figure{max-width:460px}.workspace{padding:52px 0}.proof-grid,.pro{grid-template-columns:1fr}.canvas-frame{min-height:250px;padding:7px}.mark-panel{padding:16px}.method{padding:65px 0}.method ol{grid-template-columns:1fr;gap:20px}.pro{padding:42px 16px;gap:28px}footer{align-items:flex-start;flex-direction:column;gap:7px}.paper-art b{width:58px;font-size:2rem}}@media(max-width:390px){h1{font-size:2.25rem}.topbar{width:calc(100% - 24px)}.topbar nav{gap:8px}.topbar nav a{display:none}.brand{font-size:.9rem}.intro,main>section,.legal,footer{width:calc(100% - 24px)}.actions{align-items:stretch;flex-direction:column}.actions .button{width:100%}.proof-grid{gap:16px}}@media(max-width:430px){.topbar nav a{display:none}.brand{white-space:nowrap;font-size:.76rem}.brand-dot{width:23px;height:23px;margin-right:4px}.topbar{gap:8px}}.license-ok select{width:100%;min-height:42px;margin-top:3px;padding:8px 9px;border:1px solid var(--line);border-radius:0;background:var(--paper);color:var(--ink)}.proof-figure img{display:block;width:100%;height:auto;border:2px solid var(--ink);box-shadow:11px 11px 0 var(--yellow)}