:root{--paper:#fff;--ink:#202124;--muted:#62666b;--rule:#e4e6ea;--accent:#245cc4;--serif:Didot,"Bodoni MT","Times New Roman",serif;--sans:"Helvetica Neue",Helvetica,Arial,sans-serif}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);-webkit-font-smoothing:antialiased}a{color:inherit;text-underline-offset:4px;text-decoration-thickness:1px}a:hover{color:var(--accent)}a:focus-visible{outline:2px solid var(--accent);outline-offset:5px}.skip{position:absolute;left:20px;top:-80px;padding:12px;background:white;z-index:5}.skip:focus{top:12px}.masthead{gap:20px;max-width:1400px;margin:0 auto;padding:18px 38px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--ink);font-size:14px}.masthead a{text-decoration:none}.wordmark{font-size:25px;font-weight:800;letter-spacing:-1px;line-height:1.1}.article-header{max-width:1240px;margin:32px auto 28px;padding:0 38px}.status{font-size:12px;line-height:1.5;color:var(--muted);margin:0 0 14px}h1{font-family:var(--serif);font-weight:400;font-size:clamp(38px,5vw,68px);line-height:1.08;letter-spacing:-1.8px;margin:0 0 14px}.standfirst{font-size:18px;line-height:1.5;max-width:850px;color:var(--muted);margin:0 0 20px}nav{display:flex;gap:28px;flex-wrap:wrap;font-size:14px}nav a{text-decoration:none;border-bottom:1px solid var(--rule);padding-bottom:5px}.wide{max-width:1360px;margin:50px auto 90px;padding:0 24px}.wide img{display:block;width:100%;height:auto}.wide>a{display:block}.lead-figure{margin-top:0}.wide figcaption{max-width:850px;margin:18px auto 0;color:var(--muted);font-size:13px;line-height:1.6}.wide figcaption span{font-weight:700;color:var(--ink);margin-right:10px}.wide figcaption a{white-space:nowrap;margin-left:6px}.prose{max-width:740px;margin:0 auto 72px;padding:0 28px;scroll-margin-top:40px}.prose h2{font-family:var(--serif);font-size:48px;font-weight:400;line-height:1.12;letter-spacing:-1px;margin:0 0 28px}.prose p{font-size:18px;line-height:1.8;margin:0 0 22px}.prose strong{font-weight:600}.note{font-size:15px;line-height:1.75;border-left:2px solid var(--accent);padding:4px 0 4px 22px;margin:35px 0;color:var(--muted)}.note strong{color:var(--ink)}.directions{list-style:none;padding:0;margin:30px 0}.directions li{border-top:1px solid var(--rule);padding:24px 0 4px}.directions h3{font-size:19px;margin:0 0 7px}.directions p{font-size:17px;color:var(--muted)}.methods{padding-top:35px;border-top:1px solid var(--rule)}.methods h2{font-family:var(--sans);font-size:20px;letter-spacing:0;font-weight:600}.methods p{font-size:14px;color:var(--muted);line-height:1.8}.methods code{font-size:12px;overflow-wrap:anywhere}.footer{max-width:1324px;margin:100px auto 0;border-top:1px solid var(--rule);padding:26px 28px 40px;display:flex;justify-content:space-between;gap:30px;font-size:12px;color:var(--muted);line-height:1.7}.footer span:last-child{max-width:420px}
@media(max-width:700px){html{scroll-padding-top:16px}.masthead{margin:0 20px;padding:16px 0}.article-header{margin:26px auto 24px;padding:0 24px}.status{font-size:12px}h1{letter-spacing:-1px;font-size:clamp(36px,7vw,48px)}.standfirst{font-size:16px}.desktop-break{display:none}nav{gap:14px 24px;font-size:13px}.wide{padding:0 8px;margin:30px auto 52px}.lead-figure{margin-top:0}.wide figcaption{padding:0 16px;font-size:12px}.prose{padding:0 24px;margin-bottom:50px}.prose h2{font-size:38px}.prose p{font-size:17px}.note{font-size:14px}.footer{margin-top:60px;display:block}.footer span{display:block;margin-bottom:12px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{nav,.masthead>a:last-child,.skip{display:none}.article-header{margin:30px auto}.wide,.prose{break-inside:avoid}.footer{margin-top:30px}h1{font-size:70px}}
.chart-controls{display:flex;justify-content:flex-end;gap:4px;margin:0 3% 8px}.chart-controls[hidden]{display:none}.chart-controls button{font:inherit;font-size:14px;min-width:76px;min-height:44px;padding:10px 18px;border:1px solid var(--rule);background:var(--paper);color:var(--muted);cursor:pointer}.chart-controls button[aria-pressed="true"]{background:var(--ink);border-color:var(--ink);color:white}.chart-controls button:hover{border-color:var(--ink)}.chart-controls button:focus-visible,summary:focus-visible{outline:2px solid var(--accent);outline-offset:4px}.wide figcaption .chart-description{font-weight:400;color:var(--muted);margin-right:0}.chart-fallback{font-size:13px;text-align:center}.video-figure{max-width:1120px;margin-top:-35px}.video-figure iframe{display:block;width:100%;height:auto;aspect-ratio:16/9;border:0}.methods summary{font-size:18px;font-weight:600;cursor:pointer;margin-bottom:22px}.methods[open] summary{margin-bottom:26px}@media print{.chart-controls{display:none}}@media(max-width:700px){.chart-controls{margin-right:16px}.video-figure{margin-top:-20px}}

.masthead{isolation:isolate;padding-top:8px;padding-bottom:8px}.masthead-logo{display:block;width:210px;height:auto;filter:brightness(1.06);mix-blend-mode:multiply}@media(max-width:700px){.masthead{padding-top:6px;padding-bottom:6px}.masthead-logo{width:168px}}