:root{--mist:#f0f2f0;--paper:#fcfcf8;--navy:#173d4c;--ink:#243e46;--muted:#5c6f72;--copper:#a85c35;--line:#d1dad7;--soft:#e5ece8;--error:#963e31;--radius:8px;--sans:'Segoe UI',sans-serif;--serif:Georgia,'Times New Roman',serif}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--mist);color:var(--ink);font:16px/1.55 var(--sans)}h1,h2,h3,p{margin-top:0;text-wrap:pretty}a{color:inherit}button,input,select{font:inherit}button,a,input,select,summary{-webkit-tap-highlight-color:transparent}button,select,summary{cursor:pointer}button{min-height:46px;border:0;transition:background .15s,transform .15s}button:active{transform:translateY(1px)}button:disabled{cursor:not-allowed;opacity:.48;transform:none}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid var(--copper);outline-offset:4px}button:disabled:focus{outline:none}[hidden]{display:none!important}.skip{position:absolute;top:-100px;left:16px;background:var(--navy);color:white;padding:12px;z-index:10}.skip:focus{top:12px}.site-header,main,footer{max-width:1280px;margin:auto;padding-left:48px;padding-right:48px}.site-header{min-height:100px;display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--line)}.wordmark{display:inline-flex;align-items:center;gap:12px;text-decoration:none;font:24px var(--serif);color:var(--navy)}.brand-mark{width:26px;height:26px;border:3px solid var(--navy);border-radius:50%;position:relative}.brand-mark:after{content:'';position:absolute;inset:4px;border:1px solid var(--copper);border-radius:50%}nav{display:flex;gap:28px}nav a{text-decoration:none;font-size:14px;min-height:44px;display:flex;align-items:center}nav a:hover{text-decoration:underline;text-underline-offset:5px}.intro{display:grid;grid-template-columns:1.15fr 1fr;gap:48px;align-items:end;padding:64px 0 48px}.eyebrow{font-size:11px;letter-spacing:.15em;font-weight:700;color:var(--copper);margin:0 0 16px}h1{font:clamp(46px,5.2vw,72px)/1.05 var(--serif);letter-spacing:-.045em;margin:0;color:var(--navy)}.intro-copy{max-width:400px;padding-bottom:4px}.intro-copy>p{font-size:21px;line-height:1.5;margin-bottom:16px}.small-note,.field-help{color:var(--muted);font-size:13px;line-height:1.55}.workbench{display:grid;grid-template-columns:1.05fr 1fr;border:1px solid var(--line);border-radius:var(--radius);background:var(--paper);overflow:hidden;align-items:stretch}.input-panel,.result-panel{padding:36px}.input-panel{background:var(--paper)}h2{font:29px/1.15 var(--serif);letter-spacing:-.025em;margin-bottom:24px}.panel-heading .eyebrow{margin-bottom:10px}.units{display:grid;grid-template-columns:1fr 1fr;gap:16px;background:var(--mist);padding:16px;border-radius:6px;margin-bottom:30px}.units label{font-size:12px;font-weight:600}.units select{margin-top:4px;background:transparent;border:0;border-bottom:1px solid var(--line);padding:8px 0;min-height:44px;color:var(--navy);width:100%;font-size:15px}fieldset{border:0;padding:0;margin:0 0 28px;min-width:0}legend{font-size:17px;font-weight:600;margin-bottom:12px;padding:0;display:flex;align-items:center;gap:10px}.section-number{font-size:12px;border:1px solid var(--line);border-radius:50%;width:24px;height:24px;display:inline-flex;align-items:center;justify-content:center;font-weight:400;color:var(--muted)}.field-pair{display:grid;grid-template-columns:1fr 1fr;gap:16px}.field-pair label,.assumption-content>label{display:block;min-width:0;font-size:13px;font-weight:600}.field-help{margin:8px 0 0}.input-shell{position:relative;display:flex;margin-top:8px}.input-shell input{width:100%;padding-right:42px}.input-shell>span{position:absolute;right:13px;top:50%;transform:translateY(-50%);color:var(--muted);font-size:13px;font-weight:400;pointer-events:none}input[type=number]{min-width:0;width:100%;height:52px;background:var(--paper);border:1px solid #b9c9c4;border-radius:4px;padding:10px 45px 10px 13px;color:var(--navy);font-size:20px;font-variant-numeric:tabular-nums;appearance:textfield}input::-webkit-outer-spin-button,input::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}input::placeholder{font-size:16px;color:#7c8b8c}input[aria-invalid=true]{border-color:var(--error)}input:hover{border-color:var(--navy)}details{border-top:1px solid var(--line);border-bottom:1px solid var(--line)}summary{min-height:54px;display:list-item;list-style-position:inside;padding:15px 0;font-weight:600;font-size:14px}.summary-detail{font-size:11px;font-weight:400;color:var(--muted);float:right;padding-top:3px}.assumption-content{padding:0 0 20px}.assumption-content>p{font-size:13px;color:var(--muted)}.assumption-content .field-pair{margin-top:16px}.assumption-content .field-pair input{margin-top:8px;padding-right:12px}.form-actions{display:flex;flex-direction:column;gap:8px;margin-top:24px}.primary{background:var(--navy);color:var(--paper);border-radius:4px;padding:14px 18px;font-weight:600;display:flex;justify-content:space-between;align-items:center}.primary:hover{background:#244f5e}.primary span{font-size:22px}.text-button{color:var(--navy);background:transparent;text-decoration:underline;text-underline-offset:4px;font-size:13px;padding:8px 12px}.text-button:hover{background:var(--soft)}.result-panel{background:var(--soft);border-left:1px solid var(--line);position:relative}.result-panel>.eyebrow{color:var(--muted)}.result-panel h2{margin-bottom:24px}.empty-result{padding:32px 8px;text-align:center;max-width:350px;margin:20px auto}.empty-result p{max-width:260px;margin:20px auto 0}.spool-illustration{height:160px;width:160px;margin:0 auto 32px;border-radius:50%;border:1px solid #a2b6af;position:relative;background:repeating-radial-gradient(circle,transparent 0,transparent 9px,#b9c9c3 10px,transparent 11px)}.spool-illustration:after{content:'';position:absolute;width:32px;height:32px;background:var(--soft);border:2px solid var(--navy);border-radius:50%;top:62px;left:62px}.spool-illustration i{position:absolute;left:75%;top:78%;width:58px;height:35px;border-bottom:2px solid var(--copper);transform:rotate(-20deg)}.spool-illustration span{position:absolute;left:20px;top:20px;right:20px;bottom:20px;border:3px solid var(--navy);border-radius:50%}.notice{background:#f6f1e4;border:1px solid #d4c59f;color:var(--ink);padding:14px;border-radius:4px;font-size:14px;margin:16px 0}.notice.error{background:#f8ebe7;border-color:#ccaea3;color:var(--error)}.answer-top{margin-top:32px}.result-tag{font-size:11px;letter-spacing:.12em;font-weight:600;color:var(--muted)}.answer{display:flex;align-items:baseline;gap:12px;margin:8px 0;color:var(--navy);overflow-wrap:anywhere}.answer>span:first-child{font:clamp(52px,5.5vw,76px)/1.05 var(--serif);letter-spacing:-.04em}.answer>span:last-child{font-size:24px}.answer-top>p{font-size:14px;color:var(--muted);max-width:360px}.result-panel.overflow .answer{color:var(--error)}.result-panel.overflow .answer>span:first-child{font-size:45px}.capacity-bar{height:16px;display:flex;background:#c8d4ce;border-radius:3px;overflow:hidden;margin-top:26px}.capacity-bar span{height:100%;transition:width .2s}#main-bar{background:var(--navy)}#backing-bar{background:var(--copper)}.bar-legend{display:flex;gap:16px;align-items:center;margin:10px 0 28px;flex-wrap:wrap;font-size:11px;color:var(--muted)}.bar-legend span{display:flex;align-items:center;gap:6px}.bar-legend i{width:7px;height:7px;border-radius:50%;display:inline-block}.main-dot{background:var(--navy)}.backing-dot{background:var(--copper)}.bar-legend strong{font-weight:500;margin-left:auto}.sensitivity{border-top:1px solid #c3d0c8;padding-top:24px}.sensitivity .eyebrow{color:var(--muted);margin-bottom:10px}.range-answer{font:28px/1.25 var(--serif);margin:0 0 8px}.sensitivity>p:last-child{font-size:13px;color:var(--muted)}.result-facts{margin:24px 0}.result-facts>div{display:flex;justify-content:space-between;gap:12px;padding:11px 0;border-bottom:1px solid #cbd6ce;font-size:13px}.result-facts dt{color:var(--muted)}.result-facts dd{margin:0;text-align:right;font-weight:600}.math-details{border:0}.math-details summary{font-size:13px}.formula-step{font-size:13px;overflow-wrap:anywhere;margin:0 0 12px}.formula-step strong{display:block;font-weight:600}.formula-step code{font:13px/1.7 Consolas,monospace}.report-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:24px}.secondary{background:transparent;border:1px solid #a5b8af;border-radius:4px;padding:10px 15px;color:var(--navy);font-size:13px;font-weight:600}.secondary:hover{background:#d5e0d9}.result-caution{font-size:12px;color:var(--muted);margin:24px 0 0}.action-status{font-size:13px;color:var(--navy);min-height:20px;margin:16px 0 0}.comparison{padding:40px 0;border-bottom:1px solid var(--line)}.comparison-heading{display:flex;justify-content:space-between;gap:16px;align-items:center}.comparison h2{margin-bottom:12px}.comparison p{color:var(--muted);font-size:14px;max-width:650px}.table-scroll{overflow-x:auto;max-width:100%;margin:24px 0}table{border-collapse:collapse;width:100%;font-size:14px;text-align:left}th,td{padding:14px 18px;border:1px solid var(--line);vertical-align:top;overflow-wrap:anywhere}thead th{background:var(--soft);font-weight:600}thead th span{display:block;font-size:11px;color:var(--muted);font-weight:400}tbody th{font-weight:400;color:var(--muted);width:35%}td{font-variant-numeric:tabular-nums;width:32.5%}.explanation{display:grid;grid-template-columns:1fr 1fr;gap:72px;padding:64px 0}.explanation h2{font-size:36px}.explanation>div:last-child p{color:var(--muted);font-size:15px}.inline-link{display:inline-block;text-decoration:none;border-bottom:1px solid var(--copper);padding:8px 0;font-size:14px;color:var(--navy)}.inline-link:hover{color:var(--copper)}footer{display:flex;gap:32px;align-items:center;padding-top:28px;padding-bottom:36px;border-top:1px solid var(--line)}footer .wordmark{font-size:20px}footer p{margin:0;font-size:12px;color:var(--muted)}footer nav{margin-left:auto}.sr-only{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.prose{max-width:800px;padding-top:64px;padding-bottom:64px}.prose h1{font-size:52px;margin-bottom:32px}.prose h2{margin-top:40px;margin-bottom:16px}.prose p,.prose li{font-size:16px;color:var(--muted)}.prose li{margin-bottom:10px}.prose code{background:var(--soft);padding:2px 5px;overflow-wrap:anywhere;font-size:14px}.prose .formula-box{background:var(--soft);padding:24px;border-radius:8px;overflow-wrap:anywhere}.prose .formula-box p{color:var(--navy);font-family:Consolas,monospace;font-size:14px}.prose a{color:var(--navy);text-underline-offset:3px}.prose .eyebrow{color:var(--copper);font-size:11px}.stale #result{opacity:.4}.stale #result .report-actions{opacity:1}
@media(max-width:1000px){.site-header,main,footer{padding-left:28px;padding-right:28px}.input-panel,.result-panel{padding:28px}.intro{gap:24px}.intro-copy>p{font-size:18px}.bar-legend{gap:10px}.summary-detail{float:none;display:block;margin-left:18px}.explanation{gap:32px}.answer>span:first-child{font-size:58px}}@media(max-width:720px){.site-header{min-height:80px}.site-header,main,footer{padding-left:20px;padding-right:20px}.wordmark{font-size:21px}.site-header nav{gap:16px}.site-header nav a{font-size:12px}.site-header nav a:first-child{max-width:74px;line-height:1.3}.intro{grid-template-columns:1fr;padding:40px 0 32px;gap:24px}.intro h1{font-size:54px}.intro-copy{max-width:100%}.intro-copy>p{font-size:18px;margin-bottom:10px}.workbench{grid-template-columns:1fr}.input-panel,.result-panel{padding:24px}.result-panel{border-left:0;border-top:1px solid var(--line)}.result-panel h2{font-size:28px}.summary-detail{float:right;margin-left:0;display:inline}.answer>span:first-child{font-size:70px}.empty-result{padding-top:8px;padding-bottom:20px}.spool-illustration{width:130px;height:130px;margin-bottom:20px}.spool-illustration:after{left:47px;top:47px}.explanation{grid-template-columns:1fr;gap:12px;padding:40px 0}.explanation h2{font-size:32px;margin-bottom:12px}.comparison-heading{align-items:flex-start;flex-direction:column;gap:0}th,td{padding:11px 8px;font-size:12px}.comparison h2{font-size:27px}.comparison .secondary{margin:0 5px 8px 0}footer{flex-wrap:wrap;gap:12px;align-items:flex-start}footer p{flex-basis:100%;order:3}footer nav{gap:18px}.prose{padding-top:40px}.prose h1{font-size:42px}.prose h2{font-size:26px}}@media(max-width:380px){.site-header,main,footer{padding-left:14px;padding-right:14px}.input-panel,.result-panel{padding:19px}.field-pair{gap:10px}.intro h1{font-size:48px}.units{gap:10px;padding:12px}.summary-detail{float:none;display:block;margin-left:18px}.answer>span:first-child{font-size:60px}.wordmark{font-size:19px}.site-header nav{gap:12px}.input-shell>span{right:10px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation:none!important;transition:none!important}}