:root{--ink:#171719;--paper:#f6f5f2;--muted:#5f5d56;--line:#d8d5cd;--accent:#c94a2c;--link:#a93820;--soft:#e08a6f;--white:#f1f0ec}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--paper);color:var(--ink);font-family:'IBM Plex Sans',system-ui,sans-serif;font-size:17px;line-height:1.75;-webkit-font-smoothing:antialiased}
img,svg{max-width:100%}
a{color:var(--link);text-underline-offset:.22em;text-decoration-thickness:1px}
a:hover{text-decoration-thickness:2px}
a:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:5px}
h1,h2,h3{font-family:'Archivo',system-ui,sans-serif;line-height:1.15;letter-spacing:-.025em;text-wrap:balance}
h1{font-size:clamp(2.65rem,5.5vw,4.6rem);font-weight:800;max-width:18ch;margin:18px 0 24px}
h2{font-size:clamp(1.7rem,3vw,2.15rem);font-weight:700;margin:0 0 22px}
h3{font-size:1.2rem;margin:0 0 12px}
p{margin:0 0 20px;text-wrap:pretty}
ul,ol{padding-left:1.35em}
li+li{margin-top:12px}
.wrap{width:min(1180px,100%);padding-inline:40px;margin-inline:auto}
.skip-link{position:fixed;top:12px;left:16px;z-index:10;padding:10px 16px;background:var(--paper);color:var(--ink);transform:translateY(-180%)}
.skip-link:focus{transform:translateY(0)}
.site-header{background:#0e0e10;color:var(--white);border-bottom:1px solid #343330}
.nav-bar{min-height:88px;display:flex;align-items:center;justify-content:space-between;gap:24px}
.brand{display:inline-flex;align-items:center;gap:12px;font-family:'Archivo',system-ui,sans-serif;font-weight:800;font-size:25px;color:var(--white);text-decoration:none;white-space:nowrap}
.brand svg{width:42px;height:24px;color:var(--accent)}
.primary-nav{display:flex;gap:26px;align-items:center;font-size:14px}
.primary-nav a{color:var(--white);text-decoration:none}
.primary-nav a:hover{text-decoration:underline}
.primary-nav .contact-link{padding:8px 14px;border:1px solid #6c6962;border-radius:4px}
.hero{background:#161618;color:var(--white);padding:34px 0 66px}
.breadcrumb{font-size:13px;color:#bdbbb4;margin-bottom:42px}
.breadcrumb ol{display:flex;flex-wrap:wrap;gap:10px;list-style:none;margin:0;padding:0}
.breadcrumb li+li{margin:0}
.breadcrumb li+li::before{content:'/';margin-right:10px;color:#8f8c83}
.breadcrumb a{color:#bdbbb4}
.eyebrow{font-family:'IBM Plex Mono',monospace;font-size:11px;letter-spacing:.16em;text-transform:uppercase;font-weight:600;color:var(--soft)}
.hero .lead{font-size:20px;line-height:1.65;color:#c7c5be;max-width:65ch;margin-bottom:0}
.byline{font-size:13px;color:#bdbbb4;margin:22px 0 0}
.byline a{color:#bdbbb4}
.guide-layout{display:grid;grid-template-columns:230px minmax(0,1fr);gap:76px;padding-block:64px 84px}
.toc{align-self:start;position:sticky;top:30px;font-size:14px;line-height:1.55;border-top:2px solid var(--accent);padding-top:18px}
.toc h2{font-family:'IBM Plex Mono',monospace;font-size:10px;font-weight:500;letter-spacing:.15em;text-transform:uppercase;color:var(--muted);margin-bottom:20px}
.toc ol{list-style:none;padding:0;margin:0}
.toc li+li{margin-top:16px}
.toc a{color:var(--ink);text-decoration:none}
.toc a:hover{color:var(--link);text-decoration:underline}
.article{max-width:740px;min-width:0}
.article section{scroll-margin-top:28px;margin-bottom:48px}
.article section+section{border-top:1px solid var(--line);padding-top:36px}
.article section:last-child{margin-bottom:0}
.article li{padding-left:4px}
.article strong{font-weight:600}
.summary{border-left:3px solid var(--accent);padding:2px 0 2px 24px;margin:0 0 42px;font-size:19px;line-height:1.6}
.summary p{margin:0}
.steps{list-style:none;counter-reset:step;padding:0;margin:28px 0}
.steps li{counter-increment:step;display:grid;grid-template-columns:32px 1fr;gap:18px;margin-top:22px;padding:0}
.steps li::before{content:'0' counter(step);font-family:'IBM Plex Mono',monospace;font-size:13px;font-weight:600;color:var(--link);padding-top:2px}
.steps li p{margin:4px 0 0;color:var(--muted)}
.note{background:#ebe8e0;padding:24px 28px;margin:28px 0;border-radius:2px}
.note p:last-child{margin-bottom:0}
.formula{background:#171719;color:var(--white);padding:25px 28px;margin:26px 0;font-size:18px;line-height:1.6;border-left:3px solid var(--accent)}
.formula p{margin:0}
.formula small{display:block;font-size:13px;color:#bdbbb4;margin-top:12px}
.term-list{margin:24px 0}
.term-list dt{font-weight:600;margin-top:20px}
.term-list dd{margin:4px 0 0;color:var(--muted)}
.reading{font-size:14px;color:var(--muted)}
.related{background:#eae7df;border-top:1px solid var(--line);padding:60px 0 68px}
.related-grid{display:grid;grid-template-columns:1fr 1fr;gap:36px;margin-top:30px}
.related-card{border-top:2px solid var(--accent);padding-top:20px}
.related-card a{color:var(--ink);font-family:'Archivo',system-ui,sans-serif;font-weight:700;font-size:22px;line-height:1.3;text-decoration:none}
.related-card a:hover{text-decoration:underline}
.related-card p{margin:12px 0 0;color:var(--muted);font-size:16px}
.contact{background:#161618;color:var(--white);padding:65px 0}
.contact-inner{display:flex;align-items:center;justify-content:space-between;gap:40px}
.contact h2{margin-bottom:14px}
.contact p{color:#bdbbb4;margin:0;max-width:57ch;font-size:16px}
.button{display:inline-flex;flex-shrink:0;justify-content:center;background:var(--accent);color:#fff;padding:13px 21px;border-radius:4px;text-decoration:none;font-weight:600;font-size:15px}
.button:hover{background:#ad3c23;text-decoration:none}
.site-footer{background:#0e0e10;color:#bdbbb4;padding:32px 0;font-size:13px;border-top:1px solid #343330}
.footer-inner{display:flex;align-items:flex-start;justify-content:space-between;gap:32px}
.site-footer p{margin:0;max-width:62ch}
.site-footer a{color:#bdbbb4}
@media(max-width:900px){.guide-layout{grid-template-columns:180px minmax(0,1fr);gap:38px}.wrap{padding-inline:26px}.contact-inner{align-items:flex-start;flex-direction:column;gap:24px}}
@media(max-width:650px){body{font-size:16px}.wrap{padding-inline:22px}.nav-bar{min-height:84px;gap:12px;flex-wrap:wrap;padding-block:17px}.brand{font-size:22px}.primary-nav{font-size:12px;gap:15px}.primary-nav .contact-link{padding:6px 9px}.hero{padding:24px 0 44px}.breadcrumb{margin-bottom:30px}.hero .lead{font-size:18px}.guide-layout{display:block;padding-block:36px 52px}.toc{position:static;margin-bottom:38px}.toc ol{display:flex;flex-wrap:wrap;gap:10px 22px}.toc li+li{margin-top:0}.toc h2{margin-bottom:14px}.article section{margin-bottom:36px}.article section+section{padding-top:28px}.summary{font-size:18px}.note,.formula{padding:20px}.related{padding:42px 0}.related-grid{grid-template-columns:1fr;gap:30px}.contact{padding:46px 0}.footer-inner{flex-direction:column;gap:18px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}