:root{--paper:#f6f5ef;--ink:#203d35;--muted:#64736b;--green:#174d43;--orange:#c45831;--line:#d9ddd4;--serif:Georgia,'Times New Roman',serif;--sans:Arial,Helvetica,sans-serif;font-family:var(--sans);color:var(--ink);background:var(--paper);font-synthesis:none;scroll-behavior:smooth}
*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit}button,a,input,select{-webkit-tap-highlight-color:transparent}button{cursor:pointer}a{color:inherit}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #ce6d45;outline-offset:4px}button:disabled{cursor:not-allowed}[hidden]{display:none!important}.wrap{width:min(1160px,calc(100% - 80px));margin-inline:auto}.skip{position:absolute;top:-80px;left:16px;background:white;padding:14px;z-index:10}.skip:focus{top:12px}.site-header{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);height:98px}.brand{display:flex;align-items:center;gap:8px;text-decoration:none;font-family:var(--serif);font-size:24px;font-weight:bold;letter-spacing:-.7px}.brand img{margin-right:4px}.brand span{font-style:italic;font-weight:normal;color:var(--orange)}nav{display:flex;gap:32px}nav a{font-size:13px;text-decoration:none}nav a:hover{color:var(--orange)}nav span{margin-left:6px}.intro{display:flex;justify-content:space-between;align-items:center;padding:60px 0 42px}.eyebrow{font-size:10px;font-weight:700;letter-spacing:1.7px;display:flex;align-items:center;gap:9px;margin:0 0 20px}.small-line{width:23px;height:2px;background:var(--orange)}h1{font-family:var(--serif);font-size:52px;line-height:1.1;letter-spacing:-2.1px;font-weight:400;margin:0 0 20px}h1 em{font-weight:400;color:var(--green)}.lede{max-width:630px;font-size:16px;line-height:1.7;color:var(--muted);margin:0}.intro-note{flex-shrink:0;width:215px;margin-right:38px;transform:rotate(-3deg)}.note-number{display:block;font-family:var(--serif);font-size:30px;color:var(--orange)}.note-number span{font:9px var(--sans);letter-spacing:1px;color:var(--muted)}.ruler{height:51px;margin-top:18px;border-top:2px solid var(--ink);background:repeating-linear-gradient(to right,var(--ink) 0 1px,transparent 1px 12.5%);background-size:100% 13px;background-repeat:no-repeat;display:flex;justify-content:space-between;padding-top:23px}.ruler i{font:12px var(--sans)}.intro-note p{font-size:12px;line-height:1.7;color:var(--muted)}.converter{display:grid;grid-template-columns:1.16fr 1fr;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden;scroll-margin-top:20px;box-shadow:0 12px 30px #203d3507}.input-panel{padding:28px 32px 24px}.section-label{display:flex;justify-content:space-between;align-items:center;gap:10px;font-size:9px;font-weight:700;letter-spacing:1.4px}.local-note{font-size:10px;font-weight:400;letter-spacing:0;color:var(--muted);display:flex;align-items:center;gap:6px}.local-note i{height:5px;width:5px;background:#61927e;border-radius:50%}.direction{display:flex;gap:3px;padding:4px;background:#f0f2ed;border-radius:7px;margin:22px 0 25px}.direction button{background:transparent;border:none;border-radius:5px;font-size:11px;padding:11px 5px;flex:1;white-space:nowrap;color:#5e6e65}.direction button[aria-pressed=true]{background:white;color:var(--green);box-shadow:0 1px 4px #203d3515;font-weight:700}.direction button span{padding:0 4px}label{display:block;font-size:12px;font-weight:700;margin-bottom:10px}input,select{width:100%;color:var(--ink);background:#fff;border:1px solid #cbd2c9;border-radius:5px;padding:12px;min-height:45px}input[aria-invalid=true]{border-color:#b34429}.unit-input{position:relative}.unit-input input{font:36px var(--serif);padding:13px 55px 13px 16px;height:72px}.unit-input>span{position:absolute;right:19px;top:25px;font-size:17px;color:var(--muted)}.hint{font-size:11px;color:var(--muted);line-height:1.6;margin:9px 0 20px}.precision-row{display:flex;align-items:center;justify-content:space-between;gap:16px;margin:22px 0}.precision-row label{margin:0;font-weight:400}.precision-row select{width:185px;font-size:12px;background:#fafbf8}.form-actions{display:flex;gap:20px;align-items:center}.primary{background:var(--green);color:white;border:1px solid var(--green);border-radius:5px;padding:14px 18px;font-size:12px;flex:1;display:flex;align-items:center;justify-content:space-between}.primary:hover{background:#0e3a31}.text-button{border:0;background:none;color:var(--muted);font-size:12px;padding:12px 0}.text-button:hover{color:var(--ink)}.examples{display:flex;align-items:center;gap:9px;margin-top:23px}.examples>span{font-size:9px;letter-spacing:1px;color:var(--muted);margin-right:4px}.examples button{background:none;border:1px solid #e1e5dc;padding:6px 10px;border-radius:4px;font-size:11px;color:#53665c}.examples button:hover{border-color:var(--green)}.result-panel{background:var(--green);color:#f4f5e9;padding:31px 34px;display:flex;flex-direction:column;justify-content:center}.result-panel .section-label{color:#c8d6c7;font-size:9px;letter-spacing:1px}.result-badge{font-size:8px;background:#2b5f53;padding:6px 7px;border:1px solid #638173;border-radius:3px;white-space:nowrap}.result-source{font-size:13px;color:#cfdbd1;margin:31px 0 14px}.main-result{font-family:var(--serif);font-size:clamp(30px,3.3vw,44px);letter-spacing:-1.2px;line-height:1.25;margin:0 0 12px;overflow-wrap:anywhere;font-variant-numeric:lining-nums}.result-context{font-size:11px;color:#c0d1c4;margin:0 0 30px;line-height:1.5}.result-details{border-top:1px solid #4d7263;border-bottom:1px solid #4d7263;padding:18px 0;display:grid;gap:16px}.result-details>div{display:flex;align-items:baseline;justify-content:space-between;gap:15px}.result-details span{font-size:11px;color:#c0d1c4}.result-details strong{font-size:13px;font-weight:400;text-align:right;overflow-wrap:anywhere;max-width:60%}.result-bottom{display:flex;gap:15px;align-items:center;margin-top:22px}.copy-button{border:1px solid #729082;background:transparent;color:#f4f5e9;padding:9px 12px;border-radius:4px;font-size:11px}.copy-button span{margin-left:15px}.copy-button:hover{background:#2b5f53}#copy-status{font-size:11px;line-height:1.5}.result-footnote{font-size:10px;color:#c0d1c4;margin:14px 0 0;line-height:1.6}.reverse-grid{display:grid;grid-template-columns:1.35fr .8fr .8fr 1.1fr;gap:9px}.reverse-grid label{font-size:10px;white-space:nowrap}.reverse-grid input,.reverse-grid select{font-size:13px;padding:11px 7px;min-width:0}.error{font-size:12px;color:#a73620;line-height:1.5;background:#fff3ed;padding:10px;border-radius:4px}.empty-title{font:30px var(--serif);margin-top:50px}#empty-result>p:last-child{font-size:13px;line-height:1.7;color:#c0d1c4}.unit-note{display:flex;align-items:flex-start;gap:12px;padding:20px 0 0;max-width:850px}.note-icon{flex:none;display:flex;align-items:center;justify-content:center;width:17px;height:17px;border:1px solid #abb7a8;border-radius:50%;font:italic 12px var(--serif)}.unit-note p{font-size:11px;line-height:1.7;color:var(--muted);margin:0}.unit-note strong{color:#455d4f;font-weight:600}.reference{margin-top:74px;scroll-margin-top:24px}.section-heading{display:flex;justify-content:space-between;align-items:center;gap:20px}.section-heading .eyebrow{margin-bottom:12px}h2{font:normal 32px/1.15 var(--serif);letter-spacing:-.6px;margin:0 0 15px}.section-heading p:not(.eyebrow){font-size:12px;line-height:1.6;color:var(--muted);margin:0}.outline-button{padding:12px 16px;border:1px solid #b9c3b7;background:transparent;border-radius:4px;color:var(--ink);font-size:12px;white-space:nowrap}.outline-button span{margin-left:14px}.outline-button:hover{background:#e9eee5}.chart-toolbar{display:flex;justify-content:space-between;align-items:center;border-top:1px solid var(--line);padding:18px 0 14px;margin-top:27px;font-size:10px;color:var(--muted)}.separator{margin:0 8px;color:#a0ac9d}.table-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}table{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums;font-size:11px}caption{text-align:left;font-size:10px;font-weight:700;letter-spacing:.7px;color:#567060;background:#e5ebdf;padding:10px 11px;border-radius:4px 4px 0 0}thead th{font-size:9px;font-weight:400;color:#526552;background:#edf0e7;white-space:nowrap;text-align:right;padding:10px 8px}thead th:first-child{text-align:left;padding-left:11px}tbody th,tbody td{border-bottom:1px solid #e2e5db;padding:8px;text-align:right;font-weight:400}tbody th{text-align:left;padding-left:11px;font-weight:600}tbody tr.tenth{background:#e9eee1;color:#234e3a}tbody tr:hover{background:#fff}.chart-footnote{font-size:10px;line-height:1.7;color:var(--muted);margin:16px 0}.method{border-top:1px solid var(--line);margin-top:64px;padding-top:48px;display:grid;grid-template-columns:1fr 1.6fr;gap:60px}.method>div>p:not(.eyebrow){font-size:12px;line-height:1.8;color:var(--muted)}.method-content article{display:flex;gap:20px;margin-bottom:28px}.step{font:italic 20px var(--serif);color:var(--orange)}h3{font-size:14px;font-weight:600;margin:2px 0 12px}.method-content p{font-size:12px;line-height:1.8;color:var(--muted);margin:0 0 12px}.equation{font-size:12px;line-height:1.9;background:#ecefe5;padding:13px 16px;border-left:2px solid #b5c3a6}.equation strong{font-weight:500}.questions{border-top:1px solid var(--line);margin-top:34px;padding-top:39px;display:grid;grid-template-columns:1fr 1.6fr;gap:60px}.questions h2{font-size:27px}details{border-bottom:1px solid var(--line)}summary{cursor:pointer;font-size:13px;line-height:1.6;padding:15px 24px 15px 0}details:first-child summary{padding-top:0}details p{font-size:12px;line-height:1.85;color:var(--muted);max-width:600px}footer{display:flex;justify-content:space-between;align-items:center;border-top:1px solid var(--line);padding-block:29px;margin-top:65px!important}footer .brand{font-size:20px}footer p,footer>a:last-child{font-size:10px;color:var(--muted)}footer>a:last-child{text-decoration:none}
@media(min-width:1450px){.intro{padding-top:70px;padding-bottom:48px}}
@media(max-width:1000px){.wrap{width:calc(100% - 48px)}.intro-note{margin-right:0;width:170px}h1{font-size:44px}.input-panel,.result-panel{padding:24px}.converter{grid-template-columns:1.1fr 1fr}.local-note{display:none}.direction button{font-size:10px}.direction button span{padding:0}.result-details>div{flex-wrap:wrap;gap:8px}.reverse-grid{grid-template-columns:1fr 1fr}.table-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}.method,.questions{gap:32px}}
@media(max-width:700px){.wrap{width:calc(100% - 36px)}.site-header{height:76px}.brand{font-size:21px}.brand img{width:28px;height:28px}nav{gap:10px}nav a{font-size:11px}nav a:last-child{display:none}.intro{padding:37px 0 29px}.eyebrow{font-size:8px;letter-spacing:1.25px;margin-bottom:16px}h1{font-size:38px;letter-spacing:-1.7px;margin-bottom:16px}.lede{font-size:13px;line-height:1.8}.intro-note{display:none}.desktop-break{display:none}.converter{grid-template-columns:1fr}.input-panel{padding:23px 20px}.direction{margin:20px 0 22px}.direction button{padding:12px 4px;font-size:10px}.unit-input input{font-size:34px;height:65px}.unit-input>span{top:22px}.precision-row{gap:8px}.precision-row label{font-size:11px}.precision-row select{width:166px;font-size:11px}.primary{font-size:11px}.result-panel{padding:27px 23px 25px}.result-source{margin-top:26px}.main-result{font-size:37px}.result-details>div{flex-wrap:nowrap}.result-context{margin-bottom:24px}.reverse-grid{grid-template-columns:1fr 1fr}.reverse-grid label{font-size:11px}.unit-note{padding-top:17px}.unit-note p{font-size:10px}.reference{margin-top:48px}.section-heading{align-items:flex-start;flex-direction:column;gap:18px}h2{font-size:29px}.section-heading p:not(.eyebrow){font-size:11px}.outline-button{padding:10px 12px}.chart-toolbar{font-size:9px;gap:12px;align-items:flex-start;line-height:1.6}.separator{margin:0 4px}.table-grid{gap:16px 10px}table{font-size:10px}caption{font-size:9px;padding:9px 7px}thead th{font-size:8px;padding:9px 4px}thead th:first-child{padding-left:7px}tbody th,tbody td{padding:8px 4px}tbody th{padding-left:7px}.chart-footnote{font-size:9px}.method,.questions{grid-template-columns:1fr;gap:20px;margin-top:35px;padding-top:32px}.method h2 br{display:none}.method-content article{gap:14px;margin-bottom:21px}.questions h2{margin-bottom:5px}.questions summary{font-size:12px}footer{margin-top:40px!important;gap:15px;flex-wrap:wrap;padding-block:23px}footer p{display:none}footer .brand{font-size:18px}}
@media(prefers-reduced-motion:reduce){:root{scroll-behavior:auto}}
@page{size:portrait;margin:12mm}
@media print{:root,body{background:white;color:#111}.site-header,.intro,.converter,.unit-note,.method,.questions,footer,.skip,.outline-button{display:none!important}.wrap{width:100%;max-width:none;margin:0}.reference{margin:0}.reference .eyebrow{font-size:8px;margin-bottom:7px}.reference h2{font-size:23px;margin-bottom:8px}.section-heading p:not(.eyebrow){font-size:10px;color:#222}.chart-toolbar{font-size:9px;margin-top:12px;padding:9px 0}.table-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:8px}table{font-size:10px;break-inside:avoid}caption{font-size:8px;padding:6px 4px;background:#eee;color:#111}thead th{font-size:8px;padding:7px 3px;color:#111}thead th:first-child,tbody th{padding-left:4px}tbody th,tbody td{padding:6px 3px;color:#111;border-color:#ccc}.tenth th{font-weight:800}.chart-footnote{font-size:8px;color:#222;margin-top:10px}a{color:#111}}
.not-found{padding-block:90px}.not-found .lede{max-width:520px}.not-found-actions{display:flex;align-items:center;gap:18px;margin-top:32px}.not-found-actions a{text-decoration:none}.not-found-actions .primary{flex:none;gap:32px}.not-found-page h1{margin-bottom:26px}@media(max-width:700px){.not-found{padding-block:55px}.not-found-actions{align-items:stretch;flex-direction:column;max-width:310px}.not-found-actions .outline-button{text-align:center}}