/* Edition 2.4: stories carry the hierarchy; the publisher signs them. */
:root{--na-story:Georgia,"Times New Roman",serif;--na-mineral:#c8dce0}
.na-story-opening{padding-block:25px 0}
.na-compact-heading{display:flex;align-items:baseline;justify-content:space-between;gap:20px;margin-bottom:16px}
.na-compact-heading p,.na-compact-heading h1{margin:0;font:400 11px/1.5 var(--na-sans);letter-spacing:.11em;text-transform:uppercase}
.na-compact-heading a{font:12px/1.5 var(--na-sans);text-decoration:none}
.na-episode-lead{display:grid;grid-template-columns:1.18fr 1fr;background:var(--na-rust);color:var(--na-paper)}
.na-episode-landscape{display:block;min-width:0;overflow:hidden}
.na-episode-landscape img{display:block;width:100%;height:100%;min-height:380px;object-fit:cover;object-position:50% 44%;filter:none}
.na-episode-lead-copy{display:flex;flex-direction:column;justify-content:center;padding:35px 38px;min-width:0}
.na-episode-lead-copy .na-kicker{color:inherit!important;font:400 10px/1.5 var(--na-sans);letter-spacing:.11em;margin:0 0 22px}
.na-episode-lead-copy :is(h1,h2){font:700 clamp(35px,3.7vw,57px)/1.06 var(--na-story);letter-spacing:-.04em;margin:0 0 24px;max-width:12ch;color:inherit}
.na-episode-lead-copy :is(h1,h2) a{color:inherit;text-decoration:none}
.na-episode-premise{font:400 17px/1.6 var(--na-sans);max-width:34ch;margin:0 0 30px}
.na-episode-links{display:flex;flex-wrap:wrap;align-items:center;gap:15px 26px;font:400 12px/1.5 var(--na-sans)}
.na-episode-links a{color:inherit;text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:6px}
.na-episode-links a:first-child{font-weight:600}
.na-episode-links a span{margin-left:5px}
.na-landscape-credit{font:400 10px/1.5 var(--na-sans);color:var(--na-muted);margin:8px 0 0}
.na-landscape-credit a{color:inherit;text-decoration:none}.na-landscape-credit a:hover{text-decoration:underline}
.na-episode-secondary{display:grid;grid-template-columns:210px 1fr;gap:28px;padding:25px 0;border-block:1px solid var(--na-rule);margin:27px 0 0;align-items:center}
.na-secondary-landscape{display:block;overflow:hidden;aspect-ratio:1.6;background:var(--na-ink)}
.na-secondary-landscape img{display:block;width:100%;height:100%;object-fit:cover;object-position:center 46%;filter:none}
.na-episode-secondary .na-kicker{font:400 10px/1.5 var(--na-sans);letter-spacing:.09em;margin:0 0 12px;color:var(--na-muted)}
.na-episode-secondary h2{font:700 28px/1.12 var(--na-story);letter-spacing:-.025em;margin:0 0 12px;max-width:26ch}
.na-episode-secondary h2 a{color:inherit;text-decoration:none}
.na-episode-secondary>div>p:not([class]){font:15px/1.6 var(--na-sans);max-width:53ch;margin:0 0 16px}
.na-episode-secondary .na-landscape-credit{margin-top:18px;font-size:9px}
.na-podcast-edition{padding-top:25px}
.na-podcast-edition .na-frontier-selection{padding-top:46px}
.na-podcast-edition .na-compact-heading{margin-bottom:16px}
.na-home-support{display:grid;grid-template-columns:1fr 1fr;gap:42px;align-items:center;padding-top:26px;padding-bottom:32px;border-bottom:1px solid var(--na-rule)}
.na-home-support .na-episode-secondary{grid-template-columns:145px 1fr;gap:22px;margin:0;border:0;padding:0}
.na-home-support .na-secondary-landscape{aspect-ratio:.85}
.na-home-support .na-episode-secondary h2{font-size:27px}
.na-home-support .na-episode-links{gap:14px;font-size:11px}
.na-home-atlas{background:var(--na-mineral);padding:20px 22px 0;min-width:0}
.na-home-atlas h2{font:400 31px/1 var(--na-display);margin:0 0 6px;letter-spacing:-.02em}
.na-home-atlas .na-brain-study{margin:0}
.na-home-atlas .na-brain-study figcaption{border:0;padding:0 0 13px}
.na-home-atlas .na-brain-study figcaption>span{font:10px/1.5 var(--na-sans);color:#465e60}
.na-home-atlas .na-brain-drawing{margin-top:-10px}
.na-home-atlas .na-brain-label{stroke:var(--na-mineral)}
/* A short section label cannot compete with an article headline. */
.na-media-section-head h2,.na-frontier-selection .na-media-section-head h2{font:600 19px/1.3 var(--na-sans);letter-spacing:-.015em}
.na-media-section-head .na-kicker{display:none}
.na-media-section-head{margin-bottom:24px}
.na-selected-writing{padding-block:40px}
.na-selected-grid .na-story h3,.na-editorial-grid .na-story h3,.na-frontier-card h3,.na-frontier-card-copy>h3,.na-frontier-grid-four .na-frontier-card-copy h3{font:700 28px/1.18 var(--na-story);letter-spacing:-.025em}
.na-writing-lead .na-story h2{font:700 clamp(30px,3vw,42px)/1.13 var(--na-story);letter-spacing:-.03em}
.na-selected-grid .na-story-description{font-size:15px;line-height:1.65}
.na-thoughts-heading h1,.na-frontier-heading h1{font:600 28px/1.2 var(--na-sans);letter-spacing:-.025em}
.na-thoughts-heading .na-kicker,.na-frontier-heading .na-kicker{display:none}
.na-brief-header h1,.episode-view .episode-header h1{font-family:var(--na-story);font-weight:700;letter-spacing:-.03em}
.na-image-attribution{display:block;margin:8px 0 0;font:400 10px/1.5 var(--na-sans);color:var(--na-muted)}
.na-image-attribution a{color:inherit;text-decoration:none}.na-image-attribution a:hover{text-decoration:underline}
.na-research-credit a{font:inherit;flex-shrink:1}
.na-frontier-figure figcaption a{font-size:inherit;text-decoration:none;color:inherit}
.na-research-atlas{background:var(--na-mineral)}
.na-frontier-grid-four .na-frontier-card-biological-datasets :is(.na-frontier-card-copy,.na-research-credit){background:var(--na-mineral)}
.na-colophon-grid nav{font:400 16px/1.4 var(--na-sans)}
.na-colophon-grid nav a{white-space:nowrap}
.na-correspondence-cta{background:none;border:0;border-bottom:1px solid currentColor;color:var(--na-ink);padding:8px 0;gap:25px}
.na-correspondence-cta:hover{background:none;color:var(--na-rust)}
@media(min-width:1400px){.na-episode-landscape img{min-height:420px}}
@media(max-width:1000px){
 .na-episode-lead-copy{padding:28px}.na-episode-lead-copy :is(h1,h2){font-size:40px}.na-episode-premise{font-size:15px}.na-episode-landscape img{min-height:370px}
 .na-home-support{gap:25px}.na-home-support .na-episode-secondary{grid-template-columns:1fr}.na-home-support .na-secondary-landscape{aspect-ratio:2.4}.na-home-support .na-episode-secondary h2{font-size:25px}
 .na-selected-grid .na-story h3{font-size:25px}
}
@media(max-width:700px){
 .na-episode-lead{grid-template-columns:1fr}.na-episode-landscape img{height:auto;min-height:0;aspect-ratio:1.85;object-position:center 38%}
 .na-episode-lead-copy{padding:26px 25px 29px}.na-episode-lead-copy :is(h1,h2){font-size:clamp(37px,7vw,48px);max-width:18ch;margin-bottom:17px}
 .na-episode-lead-copy .na-kicker{margin-bottom:15px}.na-episode-premise{font-size:16px;max-width:44ch;margin-bottom:22px}
 .na-home-support{grid-template-columns:1fr;gap:30px}.na-home-support .na-episode-secondary{grid-template-columns:125px 1fr;gap:22px}.na-home-support .na-secondary-landscape{aspect-ratio:.8}
 .na-home-atlas{padding:20px 20px 0}.na-home-atlas h2{font-size:32px}.na-home-atlas .na-brain-drawing{margin-top:0}
 .na-episode-secondary{grid-template-columns:125px 1fr;gap:22px}.na-episode-secondary h2{font-size:25px}.na-secondary-landscape{aspect-ratio:.8}
 .na-colophon-grid nav{flex-wrap:wrap;gap:15px 25px;justify-content:flex-start;font-size:16px}
}
@media(max-width:420px){
 .na-story-opening,.na-podcast-edition{padding-top:18px}.na-compact-heading{margin-bottom:12px}
 .na-episode-secondary,.na-home-support .na-episode-secondary{grid-template-columns:90px 1fr;gap:17px;align-items:start}
 .na-episode-secondary h2,.na-home-support .na-episode-secondary h2{font-size:24px}.na-episode-secondary>div>p:not([class]){font-size:14px}
 .na-episode-secondary .na-kicker{font-size:9px}.na-episode-links{font-size:12px;gap:16px 22px}
 .na-home-support .na-episode-links{font-size:12px}.na-episode-secondary .na-landscape-credit{font-size:9px}
}
/* Explicit roles override the legacy all-headings display rule. */
body[data-brand] :is(.na-episode-lead-copy h1,.na-episode-lead-copy h2,.na-episode-secondary h2,.na-selected-grid .na-story h3,.na-editorial-grid .na-story h3,.na-writing-lead .na-story h2,.na-frontier-card h3,.na-brief-header h1){font-family:var(--na-story);font-weight:700!important}
body[data-brand] :is(.na-media-section-head h2,.na-frontier-selection .na-media-section-head h2,.na-thoughts-heading h1,.na-frontier-heading h1){font-family:var(--na-sans);font-weight:600!important}
body[data-brand] .episode-sidebar h1{font:700 clamp(30px,3vw,43px)/1.12 var(--na-story)!important;letter-spacing:-.03em}
body[data-brand] .episode-content h2{font:700 clamp(32px,3.5vw,46px)/1.12 var(--na-story)!important;letter-spacing:-.03em}
body[data-brand] .episode-chapters h3{font:600 14px/1.4 var(--na-sans)!important;letter-spacing:.04em}
body[data-brand] :is(.na-episode-lead-copy h1,.na-episode-lead-copy h2,.na-episode-secondary h2,.na-selected-grid .na-story h3,.na-editorial-grid .na-story h3,.na-writing-lead .na-story h2,.na-frontier-card h3) a{font-weight:inherit}
.na-episode-detail-art{margin:24px 0}.na-episode-detail-art img{display:block;width:100%;aspect-ratio:1.5;object-fit:cover}
.na-episode-detail-art figcaption{font:10px/1.5 var(--na-sans);margin-top:9px;color:var(--na-muted)}
body[data-brand] :is(.na-episode-lead-copy h1,.na-episode-lead-copy h2,.na-episode-secondary h2,.na-selected-grid .na-story h3,.na-editorial-grid .na-story h3,.na-writing-lead .na-story h2,.na-frontier-card h3) a{font-weight:700!important}
@media(min-width:701px){.na-home-support .na-episode-secondary{grid-template-columns:1fr;gap:18px}.na-home-support .na-secondary-landscape{aspect-ratio:2.7}.na-home-support .na-secondary-landscape img{object-position:center 60%}}
.na-research-status{font:11px/1.5 var(--na-sans);color:var(--na-muted);margin:6px 0 0}
/* Research briefs: one frame, one category, one reading order. */
.na-frontier-selection{padding-block:42px 0;margin-bottom:0}
.na-frontier-selection .na-media-section-head>div{padding:0;min-height:0;display:block}
.na-frontier-selection .na-media-section-head{margin-bottom:24px}
.na-frontier-grid,.na-frontier-grid-four{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:30px;align-items:stretch}
.na-frontier-grid .na-brief-card{display:flex;flex-direction:column;padding:0;border:1px solid var(--na-rule);background:#f8f5ed;gap:0;min-width:0}
.na-brief-card figure{margin:0}
.na-brief-card .na-frontier-art-link{display:block}
.na-frontier-grid .na-brief-card .na-frontier-art{aspect-ratio:1.7;padding:0;gap:0;display:block;width:100%;box-sizing:border-box}
.na-brief-card .na-research-picture{position:absolute;inset:0}
.na-brief-card .na-research-picture img,.na-brief-card .na-research-picture svg{width:100%;height:100%;display:block}
.na-brief-card .na-research-vaccine img{object-fit:cover}
.na-frontier-grid .na-brief-card .na-research-binder{background:white;border-bottom:1px solid var(--na-rule)}
.na-brief-card .na-research-binder .na-research-picture{inset:0;background:white;display:flex;justify-content:center}
.na-brief-card .na-research-binder img{width:auto;max-width:100%;object-fit:contain;box-sizing:border-box}
.na-brief-card .na-research-atlas .na-research-picture{padding:18px;background:var(--na-mineral)}
.na-frontier-grid .na-brief-card figcaption{padding:12px 22px 0;min-height:49px;font:12px/1.45 var(--na-sans);color:#62665a;box-sizing:border-box}
.na-brief-card figcaption a{color:inherit;text-decoration:none}.na-brief-card figcaption a:hover{text-decoration:underline}
.na-frontier-grid .na-brief-card .na-frontier-card-copy{display:flex;flex-direction:column;flex:1;padding:18px 22px 24px;background:transparent}
.na-frontier-grid .na-brief-card .na-frontier-card-copy>.na-kicker{font:400 12px/1.5 var(--na-sans);letter-spacing:.08em;color:#706047;margin:0 0 12px}
body[data-brand] .na-frontier-grid .na-brief-card h3,.bg-guide .na-frontier-grid .na-brief-card h3{font:700 34px/1.12 var(--na-story);letter-spacing:-.025em;margin:0 0 16px}
.na-frontier-grid .na-brief-card .na-frontier-card-copy>p:not(.na-kicker){font:18px/1.5 var(--na-sans);max-width:none;margin:0 0 23px}
.na-frontier-grid .na-brief-card .na-frontier-read{margin-top:auto;padding-top:15px;border-top:1px solid var(--na-rule);font:14px/1.5 var(--na-sans);display:flex;justify-content:space-between}
.na-frontier-art-link:hover{outline:0}.na-frontier-art-link:focus-visible{outline:2px solid var(--na-rust);outline-offset:3px}
/* The newsletter is an editorial invitation, with one substantial action. */
.na-newsletter.na-discovery-letter{margin:72px 0 0;padding:0;background:var(--na-ink);color:var(--na-paper);border:0}
.na-discovery-letter-inner{display:grid;grid-template-columns:1fr auto;gap:45px;align-items:center;padding-block:44px}
.na-discovery-letter .na-kicker{color:#d3c9b0;font:11px/1.5 var(--na-sans);letter-spacing:.12em;margin:0 0 16px}
body[data-brand] .na-discovery-letter h2,.bg-guide .na-discovery-letter h2{color:var(--na-paper);font:400 clamp(36px,3.9vw,52px)/1.03 var(--na-display);letter-spacing:-.02em;margin:0 0 15px}
.na-discovery-letter-inner>div>p:not(.na-kicker){font:17px/1.6 var(--na-sans);color:#e0dfd1;max-width:51ch;margin:0}
.na-letter-subscribe{display:inline-flex;align-items:center;justify-content:space-between;gap:24px;background:var(--na-paper);color:var(--na-ink)!important;border:1px solid var(--na-paper);padding:17px 21px;text-decoration:none;font:600 14px/1.5 var(--na-sans);white-space:nowrap}
.na-letter-subscribe span{font-size:21px;line-height:1}.na-letter-subscribe:hover{background:var(--na-mineral);border-color:var(--na-mineral)}
.na-letter-subscribe:focus-visible{outline:2px solid var(--na-paper);outline-offset:5px}
@media(max-width:800px){
 .na-frontier-grid,.na-frontier-grid-four{gap:22px}.na-frontier-grid .na-brief-card figcaption{padding-inline:18px;font-size:12px}
 .na-frontier-grid .na-brief-card .na-frontier-card-copy{padding:18px}.na-frontier-grid .na-brief-card .na-frontier-card-copy>p:not(.na-kicker){font-size:17px}
 body[data-brand] .na-frontier-grid .na-brief-card h3{font-size:30px}
 .na-discovery-letter-inner{grid-template-columns:1fr;gap:25px;padding-block:35px}.na-letter-subscribe{justify-self:start}
}
@media(max-width:620px){
 .na-frontier-grid,.na-frontier-grid-four{grid-template-columns:1fr;gap:26px}.na-frontier-grid .na-brief-card .na-frontier-art{aspect-ratio:1.55}
 .na-frontier-grid .na-brief-card+.na-brief-card{padding:0;border:1px solid var(--na-rule)}
 .na-frontier-grid .na-brief-card figcaption{min-height:0;padding-top:11px}.na-frontier-grid .na-brief-card .na-frontier-card-copy{padding-top:20px}
 .na-frontier-selection{padding-top:32px}.na-newsletter.na-discovery-letter{margin-top:42px}.na-discovery-letter-inner{padding-block:32px}
 body[data-brand] .na-discovery-letter h2{font-size:41px;max-width:15ch}.na-discovery-letter-inner>div>p:not(.na-kicker){font-size:16px}
}
.na-podcast-edition{padding-bottom:0}
.na-frontier-grid .na-brief-card .na-frontier-read{border-bottom:0}
.na-brief-card h3{text-wrap:balance}
@media(min-width:621px){.na-frontier-grid .na-brief-card h3{min-height:2.24em}}
/* Detail plates use the same restrained scientific framing as their cards. */
.na-brief-layout .na-research-binder{padding:0;background:#fff;border:1px solid var(--na-rule)}
.na-brief-layout .na-research-binder .na-research-picture{background:#fff}
.na-design-panel[data-spread=design] .na-volume-photo{background:#fff;border:1px solid var(--na-rule)}
.na-design-panel[data-spread=design] .na-volume-photo>img{max-height:460px}
@media(min-width:621px) and (max-width:760px){.na-frontier-grid,.na-frontier-grid-four{grid-template-columns:1fr;gap:28px}.na-frontier-grid .na-brief-card h3{min-height:0}}