:root{--ink:22,19,14;--paper:236,233,225;--muted:113,108,98;--line:rgba(var(--ink),.16);--soft:rgba(255,255,255,.22)}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:rgb(var(--paper));color:rgb(var(--ink));font-family:'Archivo',Arial,sans-serif}
body::before{content:"";position:fixed;inset:0;z-index:-3;background-image:radial-gradient(rgba(var(--ink),.045) 1px,transparent 1.4px);background-size:34px 34px;mask-image:radial-gradient(circle at 76% 24%,#000,transparent 58%);pointer-events:none}
a{color:inherit}
.guide-wrap{width:min(100% - 40px,1120px);margin:0 auto}
.guide-header{position:sticky;top:0;z-index:40;border-bottom:1px solid var(--line);background:rgba(236,233,225,.94);backdrop-filter:blur(14px)}
.guide-header-inner{min-height:74px;display:flex;align-items:center;justify-content:space-between;gap:22px}
.guide-brand{font-size:20px;font-weight:900;letter-spacing:-.02em;text-decoration:none;white-space:nowrap}
.guide-nav{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:18px;font-family:'Space Mono',monospace;font-size:10px;letter-spacing:.12em;text-transform:uppercase}
.guide-nav a{text-decoration:none;color:rgba(var(--ink),.62)}
.guide-nav a:hover,.guide-nav a[aria-current="page"]{color:rgb(var(--ink))}
.construction{position:absolute;right:max(-150px,-8vw);top:28px;width:min(46vw,520px);aspect-ratio:1;border:1px solid rgba(var(--ink),.08);border-radius:50%;pointer-events:none}
.construction::before,.construction::after{content:"";position:absolute;background:rgba(var(--ink),.07)}
.construction::before{left:50%;top:-15%;width:1px;height:130%}
.construction::after{top:50%;left:-15%;height:1px;width:130%}
.construction i{position:absolute;left:50%;top:50%;width:36%;height:1px;background:rgba(var(--ink),.12);transform-origin:left center;transform:rotate(-43deg)}
.construction i::after{content:"";position:absolute;right:-4px;top:-4px;width:9px;height:9px;border-radius:50%;background:rgba(var(--ink),.14)}
.guide-hero{position:relative;overflow:hidden;padding:clamp(78px,10vw,126px) 0 clamp(58px,7vw,88px);border-bottom:1px solid var(--line)}
.guide-hero-content{position:relative;z-index:1;max-width:930px}
.eyebrow,.kicker,.diagram-label{font-family:'Space Mono',monospace;font-size:10px;line-height:1.5;letter-spacing:.2em;text-transform:uppercase;color:rgba(var(--ink),.48)}
.guide-hero h1{max-width:930px;margin:22px 0 24px;font-size:clamp(46px,7.4vw,92px);line-height:.95;letter-spacing:-.045em;text-wrap:balance}
.guide-hero .lede{max-width:760px;margin:0;font-size:clamp(19px,2.2vw,27px);line-height:1.48;color:rgba(var(--ink),.65);text-wrap:pretty}
.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:34px}
.button{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:13px 20px;border:1px solid rgb(var(--ink));font-family:'Space Mono',monospace;font-size:10px;letter-spacing:.13em;text-transform:uppercase;text-decoration:none;transition:opacity .2s,background .2s,color .2s}
.button.primary{background:rgb(var(--ink));color:rgb(var(--paper))}
.button:hover{opacity:.72}
.article-layout{display:grid;grid-template-columns:minmax(0,760px) minmax(220px,1fr);gap:clamp(44px,7vw,94px);align-items:start;padding:clamp(66px,8vw,104px) 0}
.prose{min-width:0}
.prose h2{scroll-margin-top:108px;margin:clamp(72px,9vw,104px) 0 20px;font-size:clamp(31px,4vw,50px);line-height:1.02;letter-spacing:-.035em;text-wrap:balance}
.prose h2:first-child{margin-top:0}
.prose h3{margin:38px 0 12px;font-size:clamp(20px,2.4vw,28px);line-height:1.15;letter-spacing:-.02em}
.prose p,.prose li{font-size:clamp(16px,1.55vw,19px);line-height:1.72;color:rgba(var(--ink),.7)}
.prose p{margin:0 0 19px}
.prose ul,.prose ol{padding-left:24px;margin:18px 0 26px}
.prose li{margin:8px 0;padding-left:5px}
.prose strong{color:rgb(var(--ink))}
.prose a{text-decoration-thickness:1px;text-underline-offset:3px}
.toc{position:sticky;top:104px;padding-left:22px;border-left:1px solid var(--line)}
.toc strong{display:block;margin-bottom:16px;font-family:'Space Mono',monospace;font-size:10px;letter-spacing:.18em;text-transform:uppercase}
.toc a{display:block;margin:12px 0;font-size:13px;line-height:1.35;text-decoration:none;color:rgba(var(--ink),.52)}
.toc a:hover{color:rgb(var(--ink))}
.reading-note{margin-top:28px;padding-top:20px;border-top:1px solid var(--line);font-size:12px;line-height:1.6;color:rgba(var(--ink),.48)}
.diagram{margin:42px 0 52px;border:0;background:transparent}
.diagram figcaption{display:flex;align-items:flex-end;justify-content:space-between;gap:18px;padding:0 0 17px;border:0}
.diagram figcaption strong{display:block;margin-top:6px;font-size:17px;letter-spacing:-.01em}
.diagram-note{max-width:34ch;text-align:right;font-size:12px;line-height:1.5;color:rgba(var(--ink),.48)}
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.stat{min-height:138px;padding:22px 18px;border-right:1px solid var(--line)}
.stat:last-child{border-right:0}
.stat b{display:block;margin-top:14px;font-size:clamp(20px,2.5vw,30px);line-height:1.05;letter-spacing:-.03em}
.stat p{margin:8px 0 0;font-size:12px;line-height:1.5;color:rgba(var(--ink),.5)}
.flow{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.flow-step{position:relative;min-height:176px;padding:22px 18px;border-right:1px solid var(--line)}
.flow-step:last-child{border-right:0}
.flow-step:not(:last-child)::after{content:"→";position:absolute;right:-10px;top:25px;z-index:2;width:20px;background:rgb(var(--paper));text-align:center;font-family:'Space Mono',monospace;font-size:13px}
.flow-step b{display:block;margin:28px 0 8px;font-size:18px;line-height:1.15}
.flow-step p{margin:0;font-size:13px;line-height:1.5;color:rgba(var(--ink),.54)}
.logic-grid,.compare-grid,.rating-grid{display:grid;grid-template-columns:repeat(2,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.logic-card,.compare-card,.rating-card{padding:24px 22px;border-right:1px solid var(--line);border-bottom:1px solid var(--line)}
.logic-card:nth-child(2n),.compare-card:nth-child(2n),.rating-card:nth-child(2n){border-right:0}
.logic-card:nth-last-child(-n+2),.compare-card:nth-last-child(-n+2),.rating-card:nth-last-child(-n+2){border-bottom:0}
.rating-card:last-child:nth-child(odd){grid-column:1/-1;border-right:0}
.formula{display:block;margin:15px 0 12px;font-family:'Space Mono',monospace;font-size:clamp(18px,2.5vw,26px);font-weight:700;letter-spacing:-.03em}
.logic-card p,.compare-card p,.rating-card p{margin:0;font-size:13px;line-height:1.55;color:rgba(var(--ink),.55)}
.compare-card b,.rating-card b{display:block;margin:12px 0 8px;font-size:19px;line-height:1.2}
.timeline{display:grid;grid-template-columns:repeat(5,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.timeline-item{position:relative;min-height:162px;padding:21px 16px;border-right:1px solid var(--line)}
.timeline-item:last-child{border-right:0}
.timeline-item b{display:block;margin:20px 0 8px;font-size:17px;line-height:1.12}
.timeline-item p{margin:0;font-size:12px;line-height:1.48;color:rgba(var(--ink),.5)}
.scale{padding:22px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.scale-row{display:grid;grid-template-columns:96px 1fr 52px;gap:14px;align-items:center;margin:14px 0}
.scale-row b{font-family:'Space Mono',monospace;font-size:11px}
.track{height:7px;background:rgba(var(--ink),.08);overflow:hidden}
.track span{display:block;height:100%;background:rgb(var(--ink))}
.scale-row em{font-family:'Space Mono',monospace;font-size:10px;font-style:normal;text-align:right;color:rgba(var(--ink),.48)}
.paper-stack{padding:8px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.paper-row{display:grid;grid-template-columns:60px 1fr auto;gap:18px;align-items:center;padding:17px 0;border-bottom:1px solid var(--line)}
.paper-row:last-child{border-bottom:0}
.paper-row b{font-size:17px}
.paper-row span:last-child{font-family:'Space Mono',monospace;font-size:10px;letter-spacing:.08em;text-transform:uppercase;color:rgba(var(--ink),.5)}
.source-note,.callout{margin:34px 0;padding:20px 0;border:0;border-top:1px solid var(--line);font-size:14px;line-height:1.65;color:rgba(var(--ink),.6)}
.callout{padding-left:18px;border-top:0;border-left:3px solid rgb(var(--ink));background:transparent}
.source-note strong,.callout strong{color:rgb(var(--ink))}
.source-list{margin:20px 0 0;padding:0;list-style:none}
.source-list li{margin:10px 0;padding-left:0;font-family:'Space Mono',monospace;font-size:11px;line-height:1.55}
.cta-band{margin-top:76px;padding:clamp(30px,5vw,54px);background:rgb(var(--ink));color:rgb(var(--paper))}
.cta-band .kicker{color:rgba(var(--paper),.5)}
.cta-band h2{margin:15px 0 14px;max-width:720px;font-size:clamp(30px,4.5vw,54px);line-height:1;letter-spacing:-.035em}
.cta-band p{max-width:640px;margin:0 0 24px;color:rgba(var(--paper),.62);font-size:16px;line-height:1.6}
.cta-band .button{border-color:rgba(var(--paper),.65);color:rgb(var(--paper))}
.related{padding:0 0 92px}
.related-head{display:flex;align-items:center;gap:18px;margin-bottom:22px}
.related-head::after{content:"";height:1px;flex:1;background:var(--line)}
.related-grid,.index-grid{display:grid;grid-template-columns:repeat(3,1fr);column-gap:clamp(24px,4vw,54px);row-gap:28px}
.related-card,.index-card{display:flex;min-height:158px;flex-direction:column;justify-content:space-between;padding:19px 0 4px;border:0;border-top:1px solid var(--line);text-decoration:none;transition:border-color .2s,transform .2s}
.related-card:hover,.index-card:hover{border-color:rgb(var(--ink));transform:translateX(4px)}
.related-card b,.index-card b{display:block;margin-top:24px;font-size:19px;line-height:1.12;letter-spacing:-.02em}
.index-intro{padding:clamp(70px,9vw,110px) 0 42px}
.index-intro h1{margin:20px 0 22px;max-width:900px;font-size:clamp(50px,8vw,100px);line-height:.92;letter-spacing:-.05em}
.index-intro p{max-width:720px;margin:0;font-size:clamp(18px,2.1vw,25px);line-height:1.5;color:rgba(var(--ink),.62)}
.index-section{padding:32px 0 100px}
.index-grid{grid-template-columns:repeat(2,1fr)}
.index-card{min-height:202px}
.index-card .number{font-family:'Space Mono',monospace;font-size:12px;letter-spacing:.14em;color:rgba(var(--ink),.42)}
.index-card b{font-size:clamp(24px,3vw,36px)}
.index-card p{margin:12px 0 0;font-size:14px;line-height:1.55;color:rgba(var(--ink),.56)}
.index-card:hover p,.index-card:hover .number{color:rgba(var(--ink),.72)}
.updated{display:flex;justify-content:space-between;gap:18px;padding-top:28px;margin-top:58px;border-top:1px solid var(--line);font-family:'Space Mono',monospace;font-size:10px;line-height:1.6;letter-spacing:.08em;text-transform:uppercase;color:rgba(var(--ink),.45)}
@media(max-width:880px){.article-layout{grid-template-columns:1fr}.toc{position:static;order:-1;padding:18px 0;border:0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.toc a{display:inline-block;margin:8px 16px 8px 0}.reading-note{display:none}.timeline{grid-template-columns:1fr}.timeline-item{min-height:0;border-right:0;border-bottom:1px solid var(--line)}.timeline-item:last-child{border-bottom:0}.related-grid{grid-template-columns:1fr 1fr}.construction{opacity:.65}}
@media(max-width:680px){.guide-wrap{width:min(100% - 28px,1120px)}.guide-header-inner{min-height:66px}.guide-nav a:not(:first-child){display:none}.guide-hero{padding-top:64px}.construction{right:-210px;width:420px}.stat-grid,.flow,.logic-grid,.compare-grid,.rating-grid,.related-grid,.index-grid{grid-template-columns:1fr}.stat,.flow-step,.logic-card,.compare-card,.rating-card{border-right:0;border-bottom:1px solid var(--line)}.stat:last-child,.flow-step:last-child,.logic-card:last-child,.compare-card:last-child,.rating-card:last-child{border-bottom:0}.logic-card:nth-last-child(2),.compare-card:nth-last-child(2),.rating-card:nth-last-child(2){border-bottom:1px solid var(--line)}.flow-step::after{display:none}.diagram figcaption{display:block}.diagram-note{margin-top:7px;text-align:left}.paper-row{grid-template-columns:44px 1fr}.paper-row span:last-child{grid-column:2}.scale-row{grid-template-columns:78px 1fr 42px}.updated{display:block}.updated span{display:block;margin:8px 0}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.related-card,.index-card{transition:none}}
@media print{.guide-header,.toc,.related,.hero-actions,.cta-band,dc-import[name="cookie-banner"]{display:none!important}.guide-hero{padding:32px 0}.article-layout{display:block;padding:36px 0}.prose h2{break-after:avoid;margin-top:42px}.diagram{break-inside:avoid}}