:root{--ink: #1a2333;--ink-soft: #4a5568;--ink-faint: #8b94a3;--paper: #ffffff;--paper-soft: #f6f8fa;--line: #e2e8f0;--brand: #1554d6;--brand-dark: #0f3da0;--brand-soft: #e8effc;--accent: #0e7c5b;--radius: 8px;--content-width: 60rem}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;font-size:1.0625rem;line-height:1.65;color:var(--ink);background:var(--paper)}a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}h1,h2,h3{line-height:1.25;color:var(--ink)}h1{font-size:2rem;margin:.5rem 0 1rem}h2{font-size:1.45rem;margin:2.25rem 0 .75rem}h3{font-size:1.15rem;margin:1.5rem 0 .5rem}code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.95em;background:var(--paper-soft);border:1px solid var(--line);border-radius:4px;padding:.1em .35em}.wrap{max-width:var(--content-width);margin:0 auto;padding:0 1.25rem}.site-header{border-bottom:1px solid var(--line);background:var(--paper)}.site-header .wrap{display:flex;flex-wrap:wrap;align-items:center;gap:.25rem 1.5rem;padding-top:.75rem;padding-bottom:.75rem}.logo{font-weight:700;font-size:1.15rem;color:var(--ink);white-space:nowrap}.logo:hover{text-decoration:none}.logo span{color:var(--brand)}.main-nav{display:flex;flex-wrap:wrap;align-items:center;gap:.25rem 1rem;font-size:.95rem}.site-searchbar{position:sticky;top:0;z-index:40;background:var(--paper-soft);border-bottom:1px solid var(--line)}.site-searchbar .wrap{padding-top:.6rem;padding-bottom:.6rem}.site-search{display:flex;align-items:center;gap:.9rem}.site-search-label{font-size:.9rem;font-weight:600;color:var(--ink-soft);white-space:nowrap}.site-search-field{position:relative;flex:1;min-width:0}.site-search-icon{position:absolute;left:.95rem;top:50%;width:1.05rem;height:1.05rem;transform:translateY(-50%);color:var(--ink-faint);pointer-events:none}.site-search input{width:100%;font-size:1rem;font-family:inherit;padding:.7rem 1rem .7rem 2.6rem;border:1px solid var(--line);border-radius:999px;background:var(--paper);box-shadow:0 1px 2px #1018280a;text-overflow:ellipsis}.site-search input:focus{outline:2px solid var(--brand);outline-offset:0;border-color:var(--brand)}@media(max-width:720px){.site-search-label{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}.site-search input{font-size:16px}}.search-results{position:absolute;z-index:60;top:calc(100% + .35rem);left:0;right:0;min-width:14rem;background:var(--paper);border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 10px 30px #1018281f;padding:.35rem;max-height:24rem;overflow-y:auto}.search-results a{display:block;padding:.4rem .75rem;border-radius:6px;color:var(--ink);font-size:.9rem}.search-results a:hover,.search-results a.active{background:var(--brand-soft);color:var(--brand-dark);text-decoration:none}.search-results .search-caption{padding:.3rem .75rem .15rem;font-size:.75rem;font-weight:600;letter-spacing:.02em;text-transform:uppercase;color:var(--ink-faint)}.search-results .search-status{padding:.4rem .75rem;font-size:.85rem;color:var(--ink-soft)}.main-nav>a{color:var(--ink-soft);padding:.25rem 0}.main-nav>a:hover{color:var(--brand)}.menu-categories{position:relative}.menu-categories>summary{cursor:pointer;list-style:none;color:var(--ink-soft);padding:.25rem 0}.menu-categories>summary::-webkit-details-marker{display:none}.menu-categories>summary:after{content:" ▾";font-size:.8em;color:var(--ink-faint)}.menu-categories[open]>summary{color:var(--brand)}.menu-panel{position:absolute;z-index:50;top:100%;left:50%;transform:translate(-50%);min-width:16rem;background:var(--paper);border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 10px 30px #1018281f;padding:.75rem 1rem;columns:1}.menu-panel a{display:block;padding:.3rem 0;color:var(--ink-soft);white-space:nowrap}.menu-panel a:hover{color:var(--brand)}.menu-toggle{display:none}@media(max-width:720px){.menu-toggle{display:inline-flex;margin-left:auto;font:inherit;font-size:.9rem;font-weight:600;padding:.35rem .8rem;border:1px solid var(--line);border-radius:999px;background:var(--paper);color:var(--ink);cursor:pointer}.menu-toggle[aria-expanded=true]{border-color:var(--brand);color:var(--brand)}.js-nav .main-nav{display:none;width:100%}.js-nav .nav-open .main-nav{display:flex;flex-direction:column;align-items:flex-start;gap:.5rem;padding:.5rem 0}}@media(max-width:720px){.menu-panel{position:static;transform:none;box-shadow:none;border:none;padding:.25rem 0 .25rem 1rem;min-width:0}}.breadcrumbs{font-size:.85rem;color:var(--ink-faint);margin:1rem 0 0}.breadcrumbs ol{list-style:none;display:flex;flex-wrap:wrap;gap:.35rem;margin:0;padding:0}.breadcrumbs li+li:before{content:"›";margin-right:.35rem;color:var(--ink-faint)}.breadcrumbs a{color:var(--ink-soft)}.ad-slot{margin:1.5rem 0}.concept-meta{display:flex;flex-wrap:wrap;gap:.5rem;font-size:.8rem;margin:.25rem 0 .75rem}.pill{border:1px solid var(--line);border-radius:999px;padding:.1rem .7rem;color:var(--ink-soft);background:var(--paper-soft)}.pill--category{background:var(--brand-soft);border-color:transparent;color:var(--brand-dark)}.concept-tabs{display:flex;flex-wrap:wrap;gap:.5rem;margin:1.25rem 0}.concept-tabs a{border:1px solid var(--line);border-radius:999px;padding:.3rem 1rem;font-size:.9rem;color:var(--ink-soft)}.concept-tabs a:hover{border-color:var(--brand);color:var(--brand);text-decoration:none}.concept-tabs a[aria-current=page]{background:var(--brand);border-color:var(--brand);color:#fff}.lead{font-size:1.15rem;color:var(--ink-soft)}.aka{font-size:.95rem;color:var(--ink-soft)}.formula-block{background:var(--paper-soft);border:1px solid var(--line);border-left:4px solid var(--brand);border-radius:var(--radius);padding:1rem 1.25rem;margin:1rem 0;overflow-x:auto}.formula-block code{border:none;background:none;font-size:1.05rem;padding:0}.var-table,.bench-table,.compare-table{width:100%;border-collapse:collapse;margin:1rem 0;font-size:.95rem}.var-table th,.var-table td,.bench-table th,.bench-table td,.compare-table th,.compare-table td{border:1px solid var(--line);padding:.5rem .75rem;text-align:left;vertical-align:top}.var-table th,.bench-table th,.compare-table th{background:var(--paper-soft);font-weight:600}.table-scroll{overflow-x:auto}.mistakes-list li{margin-bottom:.5rem}.faq-item{border:1px solid var(--line);border-radius:var(--radius);margin:.75rem 0;padding:0}.faq-item summary{cursor:pointer;font-weight:600;padding:.85rem 1.1rem}.faq-item p{margin:0;padding:0 1.1rem .85rem;color:var(--ink-soft)}.worked-example{background:#f2faf7;border:1px solid #cbe8dd;border-radius:var(--radius);padding:1rem 1.25rem;margin:1rem 0}.worked-example h3{margin-top:0}.worked-example dl{display:grid;grid-template-columns:minmax(0,max-content) minmax(0,1fr);gap:.25rem 1rem;margin:0}.worked-example dt{color:var(--ink-soft);overflow-wrap:anywhere}.worked-example dd{margin:0;font-weight:600;overflow-wrap:anywhere}@media(max-width:480px){.worked-example dl{grid-template-columns:minmax(0,1fr);gap:0}.worked-example dd{margin-bottom:.5rem}}.calc-intro{color:var(--ink-soft);font-size:.95rem}.calc-modes{display:flex;flex-wrap:wrap;gap:.4rem;border:0;padding:0;margin:0 0 1rem}.calc-modes legend{font-size:.85rem;font-weight:600;color:var(--ink-soft);margin-bottom:.35rem}.calc-modes label{display:inline-flex;align-items:center;gap:.4rem;padding:.35rem .8rem;border:1px solid var(--line);border-radius:999px;font-size:.9rem;cursor:pointer}.calc-modes label.active{border-color:var(--brand);background:var(--brand-soft);color:var(--brand-dark);font-weight:600}.calc-modes input{accent-color:var(--brand)}.calc-help{font-size:.8rem;color:var(--ink-soft);margin:.25rem 0 0}.calculator{border:1px solid var(--line);border-radius:var(--radius);padding:1.25rem;margin:1rem 0;background:var(--paper);box-shadow:0 4px 16px #1018280d}.calculator h3{margin-top:0}.calc-field{margin-bottom:1rem}.calc-field label{display:block;font-size:.9rem;font-weight:600;margin-bottom:.25rem}.calc-field input{width:100%;max-width:20rem;font-size:1rem;padding:.5rem .75rem;border:1px solid var(--line);border-radius:6px}.calc-field select{font:inherit;font-size:1rem;padding:.45rem .75rem;border:1px solid var(--line);border-radius:6px;background:var(--paper);min-width:10rem}.calc-field input:focus{outline:2px solid var(--brand);outline-offset:0;border-color:var(--brand)}.calc-field .input-error{color:#b42318;font-size:.85rem;margin-top:.25rem}.calc-results{border-top:1px solid var(--line);margin-top:1rem;padding-top:1rem}.calc-result{display:flex;flex-wrap:wrap;align-items:baseline;gap:.5rem 1rem;margin:.25rem 0}.calc-result .label{color:var(--ink-soft)}.checker form{border:1px solid var(--line);border-radius:var(--radius);padding:1.25rem;margin:1rem 0;background:var(--paper);box-shadow:0 4px 16px #1018280d}.checker-field{margin-bottom:1rem}.checker-field label{display:block;font-weight:600;font-size:.9rem;margin-bottom:.25rem}.checker-field select,.checker-field textarea{width:100%;font:inherit;font-size:.95rem;padding:.5rem .75rem;border:1px solid var(--line);border-radius:6px;background:var(--paper)}.checker-field select{max-width:20rem}.checker-field textarea{resize:vertical;min-height:8rem}.checker-count,.checker-privacy,.checker-hint{font-size:.8rem;color:var(--ink-soft);margin:.35rem 0 0}.checker-submit,.checker-share{margin-top:1rem;font:inherit;font-weight:600;padding:.55rem 1.1rem;border-radius:6px;border:1px solid var(--brand);background:var(--brand);color:#fff;cursor:pointer}.checker-submit:disabled{opacity:.45;cursor:not-allowed}.checker-share{background:var(--paper);color:var(--brand)}.checker-message{padding:.75rem 1rem;border-radius:6px;background:var(--paper-soft)}.checker-results{margin:1rem 0 2rem}.checker-results h3{margin-top:.75rem}.checker-shared{font-size:.85rem;color:var(--ink-soft)}.checker-items{padding-left:0;list-style:none}.checker-items li{padding:.6rem .8rem;margin:.5rem 0;border-left:3px solid var(--line);background:var(--paper-soft);border-radius:0 6px 6px 0}.checker-flag li{border-left-color:#b42318}.checker-note li{border-left-color:var(--brand)}.checker-unclear li{border-left-color:var(--ink-faint)}.checker-links{display:block;font-size:.85rem;margin-top:.25rem}.checker-passed{margin-top:.75rem}.checker-passed summary{cursor:pointer;font-weight:600}.download-links{padding:.75rem 1rem;background:var(--paper-soft);border-radius:6px}.bridge-table{width:auto;min-width:18rem}.bridge-table td{text-align:right}.cell-total{font-weight:700}.movement-list dt{font-weight:700;margin-top:.5rem}.movement-list dd{margin:0 0 .25rem}.card-grid .tool-card{border-color:var(--brand);background:var(--brand-soft)}.tool-card h3 a{color:var(--brand-dark)}.checker-example-text{margin:.75rem 0;padding:.6rem 1rem;border-left:3px solid var(--line);background:var(--paper-soft);font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.9rem}.checker-example-flag{border-left-color:#b42318!important}.advisor-example{margin:1rem 0 1.5rem}.advisor form{border:1px solid var(--line);border-radius:var(--radius);padding:1.25rem;margin:1rem 0;background:var(--paper);box-shadow:0 4px 16px #1018280d}.advisor-followup{margin:1rem 0;padding:1rem 1.25rem;border-radius:var(--radius);background:var(--brand-soft)}.advisor-followup h3{margin:0 0 .75rem}.advisor-options{display:flex;flex-wrap:wrap;gap:.5rem}.advisor-options button{font:inherit;padding:.5rem .95rem;border-radius:999px;border:1px solid var(--brand);background:var(--paper);color:var(--brand-dark);cursor:pointer}.advisor-options button:hover{background:var(--brand);color:#fff}.advisor-options .advisor-more{border-style:dashed;color:var(--ink-soft);border-color:var(--line)}.advisor-report{margin:1rem 0 2rem}.advisor-profile{display:flex;flex-wrap:wrap;gap:.4rem;padding:0;list-style:none}.advisor-chip{padding:.25rem .7rem;border-radius:999px;background:var(--brand-soft);color:var(--brand-dark);font-size:.85rem;font-weight:600}.advisor-chip span{font-weight:400}.advisor-chip-estimated{background:var(--paper-soft);color:var(--ink-soft);border:1px dashed var(--line)}.advisor-metrics{padding-left:1.25rem}.advisor-metrics li{margin:1rem 0;padding-left:.25rem}.advisor-metrics h4{margin:0 0 .25rem;font-size:1.05rem}.advisor-metrics p{margin:.2rem 0}.advisor-note{font-size:.9rem;color:var(--ink-soft);border-left:3px solid var(--brand);padding-left:.6rem}.terms-accept{display:grid;grid-template-columns:auto 1fr;gap:.25rem .6rem;align-items:start;margin-top:1rem;padding:.75rem;background:var(--paper-soft);border-radius:6px}.terms-accept input{margin-top:.3rem;width:1.05rem;height:1.05rem}.terms-accept label{font-weight:600}.terms-accept .terms-note{grid-column:2;margin:0;font-size:.85rem;color:var(--ink-soft)}.terms-gate,.terms-reminder{font-size:.85rem;color:var(--ink-soft);margin:.5rem 0 0}.calc-result output{font-size:1.5rem;font-weight:700;color:var(--accent)}.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(15rem,1fr));gap:1rem;padding:0;margin:1.25rem 0;list-style:none}.concept-card{border:1px solid var(--line);border-radius:var(--radius);padding:1rem 1.1rem;background:var(--paper)}.concept-card h3{margin:0 0 .35rem;font-size:1.05rem}.concept-card p{margin:0;font-size:.9rem;color:var(--ink-soft)}.concept-card .card-tags{margin-top:.5rem;font-size:.75rem;color:var(--ink-faint)}.related-group h3{margin-bottom:.35rem}.related-group ul{list-style:none;margin:0 0 1rem;padding:0}.related-group li{padding:.3rem 0;border-bottom:1px dashed var(--line)}.related-group .excerpt{color:var(--ink-faint);font-size:.9rem}.hero{padding:2.5rem 0 1rem}.hero h1{font-size:2.4rem;margin-bottom:.5rem}.hero p{font-size:1.2rem;color:var(--ink-soft);max-width:44rem}.hero .hero-slogan{font-size:1.35rem;font-weight:600;color:var(--ink);margin-top:0}.site-footer{margin-top:3.5rem;border-top:1px solid var(--line);background:var(--paper-soft);font-size:.9rem}.footer-index{display:grid;grid-template-columns:repeat(auto-fill,minmax(13rem,1fr));gap:1.5rem;padding:2rem 0 1rem}.footer-index h3{font-size:.8rem;text-transform:uppercase;letter-spacing:.06em;color:var(--ink-faint);margin:0 0 .5rem}.footer-index ul{list-style:none;margin:0;padding:0}.footer-index li{padding:.15rem 0}.footer-index a{color:var(--ink-soft)}.footer-index a:hover{color:var(--brand)}.footer-legal{border-top:1px solid var(--line);padding:1rem 0 1.5rem;color:var(--ink-faint)}.editorial-meta{color:var(--muted, #566277);font-size:.9rem}.article-toc,.footer-nav{display:flex;flex-wrap:wrap;gap:.65rem 1.25rem;margin:1.5rem 0}.editorial-example{border-left:4px solid #2563eb;background:#eff6ff;padding:1rem 1.5rem;border-radius:.4rem}.eyebrow{font-size:.8rem;font-weight:700;text-transform:uppercase;letter-spacing:.06em}.example-calculation{font-weight:650;overflow-wrap:anywhere}article>section>p,article>p,.prose,.glossary-definitions{max-width:75ch}article li{margin-block:.6rem}.editorial-sources li p{margin:.25rem 0 1rem;color:var(--muted, #566277)}.glossary-definitions>div{padding:1.25rem 0;border-bottom:1px solid #dbe2ea;scroll-margin-top:6rem}.glossary-definitions dt{font-size:1.15rem;font-weight:700}.glossary-definitions dd{margin:0}.glossary-definitions p{margin-block:.5rem}[id]{scroll-margin-top:6rem}.hero-link{display:inline-block;margin-top:.75rem;font-weight:700}.table-scroll th,.table-scroll td{min-width:10rem}@media(max-width:480px){.table-scroll th,.table-scroll td{min-width:7rem}}.skip-link{position:absolute;left:1rem;top:-5rem;z-index:100;background:#fff;padding:.75rem}.skip-link:focus{top:1rem}