:root{--paper:#f3f1e9;--ink:#202520;--acid:#e9ef43;--line:#c6c8bb;--muted:#606854;--white:#fffef9}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font:17px/1.65 system-ui,-apple-system,'Segoe UI',sans-serif}a{color:inherit;text-underline-offset:4px}a:hover{color:#586614}img{display:block;max-width:100%;height:auto}button,input,select,textarea{font:inherit}a:focus-visible,button:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid #748400;outline-offset:5px}.wrap{width:min(1280px,calc(100% - 64px));margin-inline:auto}.skip{position:absolute;top:-100px;left:20px;background:var(--acid);padding:15px;z-index:5}.skip:focus{top:10px}.site-header{border-bottom:1px solid var(--line)}.mast{display:flex;align-items:center;gap:30px;padding:27px 0}.brand{font-size:34px;font-weight:950;letter-spacing:-1.8px;text-decoration:none;line-height:1;white-space:nowrap}.brand-mark{font-style:italic;color:var(--ink);background:var(--acid);display:inline-block;letter-spacing:-6px;padding:7px 13px 9px 5px;margin-right:6px;font-size:30px}.brand-dot{color:#738000}.tagline{font-size:12px;line-height:1.45;margin:0;letter-spacing:.035em}.languages{display:flex;gap:4px;margin-left:auto;font-size:12px;font-weight:750}.languages a{padding:8px;text-decoration:none}.languages [aria-current]{background:var(--ink);color:var(--paper)}.search-link{text-decoration:none;font-size:35px;line-height:1}.nav{display:flex;gap:28px;padding:15px 0;border-top:1px solid var(--line);font-size:13px;font-weight:700;align-items:center}.nav a{text-decoration:none}.nav-all{margin-left:auto}.menu-toggle{display:none}.hero{display:grid;grid-template-columns:1fr 1.05fr;gap:50px;align-items:center;padding:48px 0 45px}.eyebrow{text-transform:uppercase;font-size:10px;letter-spacing:.13em;font-weight:800;margin:0 0 14px;color:var(--muted)}h1,h2,h3{line-height:1.15;margin:0;font-weight:780}h1{font-size:clamp(40px,5.6vw,76px);letter-spacing:-3.5px}h1 em{font-style:normal;background:linear-gradient(transparent 62%,var(--acid) 62%,var(--acid) 95%,transparent 95%)}.lead{font-size:17px;line-height:1.65;max-width:430px;margin:25px 0}.button{background:var(--ink);color:var(--white);display:inline-flex;gap:36px;align-items:center;padding:15px 20px;text-decoration:none;font-size:13px;font-weight:700}.button span{color:var(--acid);font-size:21px}.button:hover{color:var(--acid)}.hero-feature{text-decoration:none;position:relative;border:1px solid var(--ink);align-self:stretch;display:flex;flex-direction:column}.hero-feature>img{width:100%;height:380px;object-fit:cover;flex:1;min-height:260px}.hero-feature>div{padding:22px 70px 22px 25px;background:var(--white);position:relative}.hero-feature .eyebrow{display:block;background:var(--acid);color:var(--ink);padding:5px 8px;width:max-content;margin-bottom:12px}.hero-feature h2{font-size:23px;letter-spacing:-.5px}.round-arrow{position:absolute;right:24px;bottom:30px;font-size:28px}.quick-routes{display:grid;grid-template-columns:repeat(4,1fr);border-block:1px solid var(--ink)}.quick-routes a{display:flex;gap:12px;align-items:flex-start;padding:24px 20px;text-decoration:none;border-right:1px solid var(--line);font-size:12px;line-height:1.5}.quick-routes a:first-child{padding-left:0}.quick-routes a:last-child{border-right:0}.quick-routes span{color:var(--muted);font-size:10px}.quick-routes b{margin-left:auto}.section-title{display:flex;align-items:end;justify-content:space-between;gap:20px;margin:68px 0 28px}.section-title h2{font-size:36px;letter-spacing:-1.3px}.section-title>a,.section-title>span{font-size:12px;white-space:nowrap}.section-title .eyebrow{margin-bottom:10px}.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:36px 28px}.card-image{display:block;overflow:hidden;margin-bottom:20px;aspect-ratio:1.6;background:#d7d9ce}.card-image img{width:100%;height:100%;object-fit:cover;transition:transform .25s}.card-image:hover img{transform:scale(1.025)}.card h3{font-size:22px;letter-spacing:-.5px;line-height:1.25}.card h3 a{text-decoration:none}.card>p:not(.eyebrow){font-size:14px;color:var(--muted);line-height:1.65;margin:13px 0}.card time{font-size:11px;color:var(--muted)}.card .eyebrow{margin-bottom:9px}.calculations{background:var(--ink);color:var(--paper);padding:36px;margin-top:65px}.calculations .section-title{margin:0 0 25px}.calculations .eyebrow{color:var(--acid)}.calc-links{display:grid;grid-template-columns:repeat(3,1fr);border-top:1px solid #666f5a}.calc-links a{display:grid;grid-template-columns:1fr 25px;text-decoration:none;padding:26px 25px 5px 0;border-right:1px solid #666f5a;margin-right:25px;align-items:end}.calc-links a:last-child{border:0;margin-right:0}.calc-symbol{grid-column:1/-1;font-size:40px;font-weight:750;color:var(--acid);margin-bottom:20px;line-height:1}.calc-links h3{font-size:18px;line-height:1.35}.calc-links a:hover{color:var(--acid)}.guide{display:grid;grid-template-columns:1fr 1fr;gap:65px;margin-top:70px;border-block:1px solid var(--line);padding:40px 0}.guide h2{font-size:34px;letter-spacing:-1px;line-height:1.2;margin-bottom:25px}.guide-main>a{text-decoration:none}.guide-main img{aspect-ratio:1.85;object-fit:cover;width:100%;margin-bottom:18px}.guide-main h3{font-size:20px;line-height:1.35}.guide-links{padding-top:12px}.guide-links>a{display:flex;align-items:start;gap:18px;border-bottom:1px solid var(--line);padding:20px 0;text-decoration:none}.guide-links>a:first-child{padding-top:0}.guide-links span{font-size:11px;color:var(--muted);padding-top:3px}.guide-links h3{font-size:18px;line-height:1.4}.guide-links p{font-size:13px;color:var(--muted);margin:8px 0 0}.guide-links b{font-size:20px}.feature-pair{display:grid;grid-template-columns:1fr 1fr;gap:30px}.feature-pair .card-image{aspect-ratio:2}.library{margin-bottom:75px}.topic-columns{display:grid;grid-template-columns:repeat(3,1fr);gap:32px;border-top:2px solid var(--ink);padding-top:26px}.topic-columns>div{border-bottom:1px solid var(--line);padding-bottom:20px}.topic-columns h3{font-size:19px;margin-bottom:16px}.topic-columns h3 a{text-decoration:none}.topic-columns>div>a{display:block;font-size:13px;line-height:1.6;margin:12px 0;text-decoration:none}.site-footer{background:#e4e6da;padding:42px 0 23px;border-top:1px solid var(--ink)}.footer-top{display:flex;justify-content:space-between;align-items:center;gap:25px}.footer-top p{font-size:14px;margin:0}.site-footer nav{display:flex;gap:25px;flex-wrap:wrap;font-size:13px;margin:35px 0}.footer-bottom{display:flex;justify-content:space-between;gap:15px;border-top:1px solid #b2b7a8;padding-top:20px;font-size:10px;color:var(--muted);letter-spacing:.06em}.crumb{font-size:12px;color:var(--muted);padding-top:30px}.article-title{max-width:1100px;font-size:clamp(32px,4.3vw,60px);letter-spacing:-2px;margin:20px 0}.article-meta{display:flex;gap:20px;font-size:11px;color:var(--muted);flex-wrap:wrap}.article-grid{display:grid;grid-template-columns:230px minmax(0,820px);gap:55px;margin:35px 0 75px}.toc{align-self:start;position:sticky;top:22px;border-top:2px solid var(--ink);padding-top:16px;font-size:12px}.toc summary{font-size:13px;font-weight:750;cursor:pointer}.toc ol{padding-left:17px;line-height:1.6}.toc li{margin:13px 0}.toc a{text-decoration:none}.reading{font-size:18px;line-height:1.75;min-width:0}.reading p{margin:20px 0}.reading h2{font-size:28px;line-height:1.3;letter-spacing:-.6px;margin:37px 0 17px;scroll-margin-top:25px}.reading h3{font-size:22px;line-height:1.4;margin:27px 0 14px}.reading li{margin:10px 0}.reading a{color:#4c6516}.reading figure{margin:0 0 30px}.reading figcaption{font-size:12px;color:var(--muted);margin-top:10px}.article-cover img{aspect-ratio:1.65;object-fit:cover;width:100%}.reading blockquote,.note,.callout,.quick-answer{padding:20px 25px;margin:25px 0;background:var(--white);border-left:4px solid var(--acid)}.formula{background:var(--ink);color:white;padding:20px}.formula strong{color:var(--acid)}.reading .source,.reading .sources{font-size:12px;color:var(--muted);border-top:1px solid var(--line);padding-top:17px}.table-wrap{max-width:100%;overflow-x:auto;margin:25px 0}table{width:100%;border-collapse:collapse;background:var(--white);font-size:14px}th,td{text-align:left;vertical-align:top;padding:13px 16px;border-bottom:1px solid var(--line)}th{background:var(--acid);font-weight:750}.article-end{border-top:2px solid var(--ink);margin-top:40px}.article-end ul{padding-left:20px}.simple-page{padding:50px 0 75px;min-height:50vh}.simple-page>h1{font-size:clamp(34px,5vw,60px);margin-bottom:22px}.simple-page>p{max-width:800px}.simple-page .cards{margin-top:35px}.prose{max-width:820px}.search-form{display:flex;max-width:800px;margin:28px 0}.search-form input{width:100%;min-width:0;padding:14px 18px;border:1px solid var(--ink);background:var(--white)}.search-form button{background:var(--acid);border:1px solid var(--ink);padding:12px 24px;white-space:nowrap;cursor:pointer}.pagination{display:flex;gap:10px;margin:40px 0;flex-wrap:wrap}.pagination a{border:1px solid var(--ink);padding:8px 16px;text-decoration:none}.pagination [aria-current]{background:var(--acid)}.notice{padding:16px;background:var(--acid)}.calculator{border:2px solid var(--ink);padding:24px;background:var(--white);margin:35px 0}.calculator h2{margin:0 0 15px}.calculator>p{font-size:14px}.fields{display:grid;grid-template-columns:1fr 1fr;gap:16px}.calculator label{font-size:13px;line-height:1.45;font-weight:650}.calculator input{display:block;width:100%;padding:10px;border:1px solid var(--line);background:var(--paper);margin-top:7px}.calculator button{border:1px solid var(--ink);background:var(--acid);font-weight:700;padding:12px 22px;margin:20px 0 0;cursor:pointer}.calculator output{display:block;font-size:16px;background:var(--paper);padding:16px;margin-top:20px}.diagram{padding:20px;background:var(--white);border:1px solid var(--line)}.diagram svg{width:100%;height:auto}.diagram figcaption{font-size:13px}[hidden]{display:none!important}@media(min-width:1600px){.hero h1{font-size:80px}}@media(max-width:1050px){.wrap{width:calc(100% - 40px)}.nav{gap:15px;font-size:12px}.hero{gap:30px}.hero h1{letter-spacing:-2px}.hero-feature>img{height:310px}.quick-routes a{padding:18px 12px}.article-grid{grid-template-columns:190px minmax(0,1fr);gap:30px}.guide{gap:30px}.tagline{max-width:165px}}@media(max-width:780px){.wrap{width:calc(100% - 36px)}.mast{gap:14px;padding:20px 0}.brand{font-size:27px;letter-spacing:-1.3px}.brand-mark{font-size:23px;letter-spacing:-5px;padding:6px 11px 8px 3px}.tagline{display:none}.languages{margin-left:auto}.search-link{font-size:30px}.menu-toggle{display:block;font-size:11px;padding:7px;border:1px solid var(--ink);background:transparent}.nav{display:none;padding:15px 0;grid-template-columns:1fr 1fr;gap:18px}.nav.open{display:grid}.nav-all{margin:0}.hero{grid-template-columns:1fr;padding-top:30px;gap:30px}.hero h1{font-size:58px;letter-spacing:-2.4px}.hero .lead{max-width:520px}.hero-feature>img{height:300px}.hero-feature h2{font-size:21px}.quick-routes{grid-template-columns:1fr 1fr}.quick-routes a,.quick-routes a:first-child{padding:17px 13px;border-bottom:1px solid var(--line)}.quick-routes a:nth-child(2){border-right:0}.quick-routes a:nth-child(n+3){border-bottom:0}.section-title{margin-top:45px}.section-title h2{font-size:29px}.section-title>span{display:none}.cards{grid-template-columns:repeat(2,minmax(0,1fr));gap:30px 20px}.card h3{font-size:20px}.calculations{padding:24px;margin-top:45px}.calc-links{grid-template-columns:1fr}.calc-links a{border-right:0;border-bottom:1px solid #666f5a;margin:0;padding:20px 0;grid-template-columns:55px 1fr 20px;gap:14px}.calc-symbol{grid-column:auto;margin:0;font-size:29px;align-self:center}.calc-links h3{font-size:17px}.guide{grid-template-columns:1fr;gap:27px;margin-top:45px;padding:30px 0}.guide h2{font-size:30px}.topic-columns{grid-template-columns:1fr 1fr;gap:24px}.footer-top{align-items:start}.footer-top p{font-size:12px}.article-grid{display:block;margin-top:28px}.toc{position:static;margin-bottom:25px}.toc ol{columns:2}.reading{font-size:17px}.article-title{letter-spacing:-1px}.reading h2{font-size:26px}.article-cover img{aspect-ratio:1.5}.simple-page{padding-top:35px}.reading table{font-size:13px}}@media(max-width:460px){.wrap{width:calc(100% - 30px)}.mast{gap:8px}.brand{font-size:23px}.brand-mark{font-size:20px;padding-right:9px;margin-right:1px}.languages{gap:0;font-size:10px}.languages a{padding:6px}.search-link{font-size:26px}.menu-toggle{padding:6px;font-size:10px}.hero h1{font-size:47px;letter-spacing:-2px}.hero .eyebrow{font-size:9px}.hero-feature>img{height:250px}.hero-feature>div{padding:20px 48px 20px 18px}.round-arrow{right:17px}.quick-routes strong{font-size:11px}.quick-routes a{gap:8px}.section-title{align-items:start;gap:15px}.section-title h2{font-size:27px;letter-spacing:-.9px}.section-title>a{font-size:11px;padding-top:5px}.cards{grid-template-columns:1fr}.card-image{aspect-ratio:1.8}.card h3{font-size:22px}.feature-pair{grid-template-columns:1fr;gap:30px}.topic-columns{grid-template-columns:1fr}.topic-columns>div{padding-bottom:12px}.footer-top{display:block}.footer-top p{margin-top:22px}.site-footer nav{gap:18px;font-size:12px}.footer-bottom{display:block}.footer-bottom span{display:block;margin:6px 0}.toc ol{columns:1}.fields{grid-template-columns:1fr}.calculator{padding:17px}.calculator h2{font-size:24px}.reading h2{font-size:24px}.article-meta{gap:10px}.search-form button{padding:10px 14px}th,td{padding:11px;min-width:110px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.card-image img{transition:none}}@media print{.site-header,.site-footer,.toc,.calculator,.article-cover,.skip{display:none}body{background:white;font-size:11pt}.wrap{width:100%}.article-grid{display:block;margin:0}.article-title{font-size:26pt}.reading{font-size:11pt}.reading h2{font-size:17pt;break-after:avoid}.table-wrap{overflow:visible}tr{break-inside:avoid}}