:root{--ink:#243a33;--muted:#6d7973;--accent:#23674d;--line:#dfe5df;--paper:#fdfdf9}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.95 'Malgun Gothic','Segoe UI',sans-serif;word-break:keep-all;overflow-wrap:anywhere}a{color:var(--accent);text-underline-offset:4px}header{height:76px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 max(28px,calc((100vw - 1220px)/2));gap:24px;background:rgba(253,253,249,.97);position:sticky;top:0;z-index:5}header a{text-decoration:none}.brand{font-weight:800;white-space:nowrap}.brand span{font-weight:400;margin-left:8px;color:var(--muted)}header nav{display:flex;gap:8px;font-size:13px}header nav a{padding:9px 16px;border-radius:7px}header nav a[aria-current]{background:#e8eee6;font-weight:700}.layout{max-width:1220px;margin:auto;display:grid;grid-template-columns:240px minmax(0,1fr);gap:80px;padding:0 28px}aside{position:sticky;top:120px;align-self:start;padding-top:55px;font-size:13px}aside nav{display:grid;gap:14px;margin:26px 0 30px}aside nav a{text-decoration:none;color:#6b7771;border-left:2px solid transparent;padding-left:14px}aside nav a.active{color:var(--accent);border-color:var(--accent);font-weight:700}.aside-note{border-top:1px solid var(--line);padding-top:24px;color:#849087;font-size:12px}.back{display:inline-block;margin-top:20px;font-size:12px}.eyebrow{color:var(--accent);font-size:12px;letter-spacing:.07em;font-weight:700}.hero{padding-top:66px!important}.hero h1{font-size:44px;letter-spacing:-2px;line-height:1.4;margin:20px 0 24px;font-weight:750}.lead{font-size:20px;line-height:1.8;color:#52685c}.hero>p:not(.eyebrow){max-width:660px}.hero-bottom{display:flex;justify-content:space-between;align-items:center;margin-top:32px;padding:20px 0 0;font-size:12px;color:var(--muted);border-top:1px solid var(--line)}.hero-bottom a{text-decoration:none;font-weight:700}main{min-width:0;max-width:800px}section{padding:55px 0 48px;border-bottom:1px solid var(--line)}h2{font-size:28px;line-height:1.55;letter-spacing:-1px;margin:12px 0 24px}h3{font-size:19px;line-height:1.65;margin:30px 0 12px}p{margin:0 0 20px}.number{font-size:12px;color:var(--accent);letter-spacing:.04em;font-weight:700;margin:0}.note,.example{background:#edf2e9;border-left:3px solid #6c946e;padding:22px 26px;margin:28px 0;border-radius:0 8px 8px 0}.note p,.example p{margin:8px 0 0;font-size:15px}.source{font-size:13px;display:inline-block;margin-top:16px}.demo{padding:26px;background:#fff;border:1px solid #cedcce;border-radius:12px;margin:28px 0;box-shadow:0 5px 18px #263e2605}.demo-title{display:flex;justify-content:space-between;gap:12px;font-size:13px;color:var(--accent)}small,.small{font-size:12px;color:var(--muted)}.sliders{display:grid;grid-template-columns:1fr 1fr;gap:32px;margin:23px 0}.sliders label{font-size:14px}.sliders output{float:right;font-weight:700;font-size:22px;line-height:1.4}.sliders input{display:block;width:100%;margin:16px 0;accent-color:var(--accent)}.answer{display:flex;gap:22px;align-items:center;background:#f2f5ee;border-radius:7px;padding:18px}.answer strong{font-size:32px;min-width:68px;text-align:center;color:var(--accent)}.answer p{margin:0;font-size:14px}.track{display:grid;grid-template-columns:repeat(10,1fr);gap:5px;margin-top:24px}.track span{text-align:center;border-radius:5px;background:#f2f3ef;font:14px/38px 'Segoe UI',sans-serif}.track .visited{background:#dce9d8}.track .goal{background:var(--accent);color:white;font-weight:700}.track .origin{outline:2px solid var(--accent);outline-offset:-2px}.demo .small{margin:12px 0 0}.cards{display:grid;gap:12px;margin:26px 0}.cards>div{border:1px solid var(--line);padding:20px 23px;border-radius:8px}.cards span{font-size:12px;color:var(--accent);font-weight:700}.cards h3{margin:4px 0;font-size:17px}.cards p{font-size:14px;margin:0;color:#5d6d64}details{border-bottom:1px solid var(--line);padding:16px 0;font-size:14px}summary{cursor:pointer;font-weight:700}details p{margin:14px 0}.flow{display:flex;gap:10px;align-items:center;margin:28px 0}.flow div{flex:1;background:#edf2e9;text-align:center;padding:18px 8px;border-radius:7px;font-size:13px;font-weight:700}.flow small{font-weight:400}.steps{padding-left:25px}.steps li{padding:8px 0 8px 12px}.steps li::marker{color:var(--accent);font-weight:700}.steps p{font-size:15px;margin:6px 0}.timeline{border-left:2px solid #cfdccb;padding-left:28px;margin:28px 0}.timeline article{margin-bottom:30px}.timeline span{font-size:12px;color:var(--accent);font-weight:700}.timeline h3{margin:5px 0 10px}.timeline p{font-size:15px}.table-wrap{overflow-x:auto}table{border-collapse:collapse;width:100%;font-size:14px}td,th{text-align:left;border-bottom:1px solid var(--line);padding:15px}th{background:#edf2e9}td:first-child{min-width:140px}.metrics{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--line);border-radius:9px;margin:28px 0;background:white}.metrics>div{padding:24px}.metrics>div+div{border-left:1px solid var(--line)}.metrics span{font-size:12px;color:var(--muted)}.metrics strong{display:block;font-size:42px;color:var(--accent);line-height:1.7;font-variant-numeric:tabular-nums}.metrics small{font-size:20px;margin-left:4px;color:inherit}.metrics p{font-size:12px;margin:0}.failure{display:flex;align-items:center;gap:24px;padding:24px 0}.failure img{image-rendering:pixelated;flex-shrink:0;border-radius:6px}.failure p{font-size:14px;margin:6px 0 0}.reading-links{display:grid;gap:12px;margin:28px 0}.reading-links a{display:block;text-decoration:none;border:1px solid var(--line);border-radius:8px;padding:22px 24px;background:white}.reading-links a:hover{border-color:var(--accent)}.reading-links span{float:right}.reading-links p{margin:8px 0 0;font-size:14px;color:#647367}.closing{padding:26px;background:#edf2e9;border-radius:8px;margin:30px 0}.closing h3{margin:0 0 14px}.closing ol{padding-left:24px;font-size:15px}.closing p{font-size:14px;margin-bottom:0}footer{display:flex;justify-content:space-between;gap:20px;color:var(--muted);font-size:11px;padding:30px 0 45px}a:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #ad7022;outline-offset:5px}.skip{position:absolute;left:20px;top:-100px;z-index:10;background:white;padding:12px}.skip:focus{top:10px}@media(max-width:1050px){.layout{gap:35px;grid-template-columns:210px minmax(0,1fr)}.hero h1{font-size:38px}}@media(max-width:780px){header{height:auto;min-height:68px;padding:14px 20px;flex-wrap:wrap;gap:10px}header nav a{padding:7px 10px;font-size:12px}.layout{display:block;padding:0 22px}aside{position:static;padding-top:25px}aside>.eyebrow,.aside-note,.back{display:none}aside nav{display:flex;overflow-x:auto;gap:15px;margin:0;padding:5px 0 15px}aside nav a{white-space:nowrap;padding:0;border:0;font-size:12px}.hero{padding-top:30px!important}.hero h1{font-size:34px}.lead{font-size:18px}section{padding:38px 0}h2{font-size:25px}.demo{padding:18px}.demo-title{display:block}.demo-title small{display:block}.sliders{gap:22px}.metrics>div{padding:18px 12px}.metrics strong{font-size:34px}.flow{gap:6px}.flow div{font-size:11px}.flow small{font-size:10px}footer{display:block}.hero-bottom{gap:20px}.failure{align-items:flex-start}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{header,aside,.skip{display:none}.layout{display:block}main{max-width:none}section{break-inside:avoid}body{font-size:12px}.hero h1{font-size:30px}}

/* Three reading pages share the same navigation. */
header nav{flex-wrap:wrap}@media(max-width:780px){header nav{width:100%;gap:3px}header nav a{font-size:11px;padding:6px 8px}}