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@media(min-width:1350px){.learn-lesson-main{gap:55px}.learn-visual{padding:30px}.learn-atlases{gap:22px}}
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@media(max-width:480px){.learn-shell{padding-inline:20px}.learn-heading{flex-direction:column;gap:20px}.learn-heading .learn-search{max-width:100%;width:100%}.learn-atlases{grid-template-columns:1fr}.learn-atlas,.learn-atlas:nth-child(-n+2),.learn-atlas:last-child{grid-column:auto}.learn-atlas .atlas-picture,.learn-atlas:nth-child(-n+2) .atlas-picture{height:225px}.learn-atlas h2{font-size:33px}.learn-lesson-head h2{font-size:38px;letter-spacing:-1.3px}.learn-visual{padding:18px}.learn-visual svg text{font-size:17px}.learn-visual svg .caption-small{font-size:14px}.learn-map-groups,.learn-map.list .learn-map-groups{grid-template-columns:1fr;gap:22px}.learn-map-lines{display:none}.learn-map-group h3{min-height:0;margin-bottom:12px;padding:0}.learn-map-node{font-size:16px;padding:13px 15px}.learn-intro{font-size:17px}.learn-connection-grid{grid-template-columns:1fr}.learn-home-links{grid-template-columns:1fr}.learn-reading-toolbar{gap:6px}.learn-breadcrumb{font-size:12px}.learn-page .header nav{gap:12px;font-size:13px}.learn-domain-nav a{font-size:13px;padding:10px}.learn-domain-nav{gap:2px}.learn-detail summary{font-size:22px}.learn-start{width:100%;justify-content:space-between}}
@media(prefers-reduced-motion:reduce){.learn-page *{scroll-behavior:auto!important;transition:none!important;animation:none!important}}

.learn-detail-intro{font-size:16px;line-height:1.8;color:var(--learn-copy);margin-top:20px}
@media(max-width:780px){.header nav{flex-wrap:wrap}.header{height:auto;flex-wrap:wrap;row-gap:16px;padding-block:24px}}

.learn-history{padding:0;margin:40px 0 0;list-style:none}.learn-history li{display:grid;grid-template-columns:190px 1fr;gap:35px;padding:0 0 38px;position:relative}.learn-history li:before{content:'';position:absolute;left:201px;top:8px;bottom:-8px;width:1px;background:#3b5675}.learn-history li:after{content:'';position:absolute;left:197px;top:8px;width:9px;height:9px;border-radius:50%;background:var(--learn-accent)}.learn-history li:last-child:before{display:none}.history-date{color:var(--learn-accent);font-size:16px;line-height:1.5}.learn-history h3{font-size:23px;line-height:1.35;letter-spacing:-.5px;font-weight:500}.learn-history h3 span{color:var(--learn-accent)}.learn-history p{font-size:16px;line-height:1.75;color:var(--learn-copy);max-width:780px;margin:12px 0}.history-source{font-size:13px;color:var(--learn-soft);text-decoration:underline;text-underline-offset:4px}.history-source:hover{color:var(--learn-accent)}
@media(max-width:780px){.learn-history li{grid-template-columns:1fr;gap:10px;padding:0 0 32px 25px}.learn-history li:before{left:4px}.learn-history li:after{left:0}.learn-history h3{font-size:21px}.history-date{font-size:14px}}

.learn-first-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:18px;margin:28px 0}.learn-first-card{display:block;position:relative;padding:24px 22px;border:1px solid var(--learn-edge);border-radius:8px;background:linear-gradient(140deg,#14253b,#0d1828)}.learn-first-card>span{display:block;color:var(--learn-accent);font-size:14px;margin-bottom:25px}.learn-first-card h3{font-size:23px;line-height:1.25;font-weight:500;letter-spacing:-.5px;padding-right:8px}.learn-first-card p{font-size:15px;line-height:1.6;color:var(--learn-copy);margin-top:15px}.learn-first-card b{position:absolute;right:17px;top:19px;color:var(--learn-accent);font-size:23px;font-weight:400}.learn-first-card:hover{border-color:var(--learn-accent)}.learn-physical-route{margin-top:55px;padding-top:35px;border-top:1px solid var(--learn-edge)}.learn-physical-route h2{font-size:30px;line-height:1.3;font-weight:450;letter-spacing:-.8px}.learn-physical-route>p{font-size:16px;line-height:1.7;color:var(--learn-copy);margin:14px 0;max-width:780px}.learn-earlier{border-top:1px solid var(--learn-edge);padding-top:23px;margin-top:28px}.learn-earlier h3{font-size:19px;line-height:1.4;font-weight:500}.learn-earlier p{font-size:14px;color:var(--learn-soft);line-height:1.6;margin-top:7px}.learn-view-switch{flex-wrap:wrap}.learn-glossary a{color:var(--learn-accent);text-decoration:underline;text-underline-offset:3px}
@media(max-width:1050px){.learn-first-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:480px){.learn-first-grid{grid-template-columns:1fr}.learn-first-card>span{margin-bottom:12px}.learn-first-card{padding:20px}.learn-view-switch button{padding:9px 11px}.learn-physical-route h2{font-size:26px}}

/* A short guided story leads into the connected atlas. */
.learn-story{max-width:790px;margin:0 auto 45px}.story-top{display:flex;align-items:center;justify-content:space-between;gap:16px;color:var(--learn-soft);font-size:13px}.story-top button{background:none;border:0;color:var(--learn-accent);font-size:13px;padding:10px 0;min-height:44px}.story-title{font-size:clamp(32px,4vw,49px);line-height:1.15;letter-spacing:-1.7px;font-weight:450;margin:22px 0}.story-progress{display:flex;gap:6px;margin:27px 0}.story-progress i{height:3px;flex:1;background:var(--learn-edge)}.story-progress i.active{background:var(--learn-accent)}.story-scene-title{font-size:16px;line-height:1.45;font-weight:500;color:var(--learn-soft);margin-bottom:16px}.story-picture{width:100%;background:var(--learn-panel);border-radius:12px;overflow:hidden}.story-picture svg{display:block;width:100%;height:auto}.story-picture text{font:16px 'Helvetica Neue',Arial,sans-serif;fill:var(--learn-light)}.story-picture text.story-small{font-size:13px;fill:var(--learn-copy)}.story-picture text.story-letter{fill:#080e1c;font-size:19px;font-weight:500}.story-node{fill:#16273d;stroke:#597393;stroke-width:1.5}.story-node.lit{fill:var(--learn-accent);fill-opacity:.18;stroke:var(--learn-accent)}circle.story-node.lit{fill-opacity:1}.story-wire{fill:none;stroke:#597393;stroke-width:2}.story-wire.lit{stroke:var(--learn-accent)}.story-copy{font-size:clamp(18px,2vw,22px);line-height:1.65;margin:24px 0 0;color:var(--learn-light)}.story-actions{display:flex;flex-wrap:wrap;gap:10px;margin:22px 0 0}.story-actions:empty{display:none}.story-actions button{border:1px solid var(--learn-edge);background:#172b43;border-radius:6px;padding:13px 18px;min-height:48px;font-size:16px;line-height:1.4;text-align:left}.story-actions button[aria-pressed=true]{border-color:var(--learn-accent);background:#283e57}.story-feedback{font-size:17px;line-height:1.65;color:var(--learn-accent);margin-top:20px}.story-nav{display:flex;justify-content:space-between;gap:15px;border-top:1px solid var(--learn-edge);margin-top:32px;padding-top:13px}.story-nav button{border:0;background:none;padding:12px 0;min-height:46px;color:var(--learn-accent);font-size:16px}.story-words,.story-evidence{font-size:14px;color:var(--learn-soft);line-height:1.65;margin-top:20px}.story-words summary,.story-evidence summary{cursor:pointer;padding:8px 0;min-height:40px}.story-words p,.story-evidence p{margin:14px 0}.story-words strong{font-weight:500;color:var(--learn-light);margin-right:6px}.story-evidence a{display:block;padding:9px 0;color:var(--learn-accent);text-decoration:underline;text-underline-offset:3px}.learn-story-toggle{display:flex;justify-content:flex-end;margin:0 0 22px}.learn-story-toggle button{background:none;border:0;color:var(--learn-accent);font-size:14px;padding:10px 0;min-height:44px}.learn-page:has(.learn-story) .learn-heading h1{font-size:36px;letter-spacing:-1px}.learn-page:has(.learn-story) .learn-heading{margin-bottom:20px}.learn-page:has(.learn-story) .learn-domain-nav{margin-bottom:20px}.learn-page:has(.learn-story) .learn-search{width:260px}.learn-page:has(.learn-story) .learn-reading-toolbar{margin-bottom:12px}.learn-atlas:nth-child(n+6){grid-column:span 2}
@media(max-width:780px){.learn-atlas:nth-child(n+6){grid-column:span 3}.learn-atlas:last-child{grid-column:span 3}.story-picture{max-width:100%}.learn-home-links{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:480px){.learn-atlas:nth-child(n+6),.learn-atlas:last-child{grid-column:auto}.learn-page:has(.learn-story) .learn-search{width:100%}.story-title{letter-spacing:-1px}.story-actions button{width:100%}.story-top{font-size:12px}.story-picture text{font-size:14px}.story-picture text.story-small{font-size:12px}.learn-home-links{grid-template-columns:1fr}}
.learn-experiment .experiment-picture svg{width:100%;max-height:none;height:auto}.learn-experiment .experiment-picture text{font-size:15px}.learn-experiment .experiment-picture .experiment-small{font-size:12px}.learn-experiment .experiment-picture .active-node+text{fill:#08111e}.learn-experiment .experiment-picture .node{fill:#172a40;stroke:#627d9e}.learn-experiment .experiment-picture .active-node{fill:var(--learn-accent);stroke:var(--learn-accent)}
@media(min-width:1051px){.learn-home-links{grid-template-columns:repeat(4,minmax(0,1fr))}}
.story-picture .learn-experiment{padding:14px}.story-picture .learn-experiment .learn-visual-caption,.story-picture .learn-experiment .learn-controls{display:none}.story-picture .learn-experiment .learn-figure-note{font-size:12px;line-height:1.6;color:var(--learn-soft);padding:4px 8px 8px}.story-words a{color:var(--learn-accent);text-decoration:underline}.learn-experiment .active-wire{stroke:var(--learn-accent);fill:none;stroke-width:2}.learn-experiment .wire{stroke:#627d9e;fill:none;stroke-width:2}.learn-experiment text{fill:var(--learn-light)}
.learn-page:has(.learn-story) .learn-heading,.learn-page:has(.learn-story) .learn-domain-nav{display:none}
@media(max-width:480px){.learn-heading h1{font-size:clamp(36px,10vw,48px);letter-spacing:-1.8px}}

.learn-pathway{margin:36px 0;padding:28px;border:1px solid var(--learn-edge);border-radius:12px;background:#101e31}.learn-pathway h2{font-size:clamp(26px,3vw,37px);line-height:1.2;letter-spacing:-1px;margin:10px 0 15px}.learn-pathway>p{max-width:750px;color:var(--learn-copy);font-size:17px;line-height:1.6}.learn-pathway .eyebrow{font-size:11px;color:var(--learn-accent)}.learn-pathway ol{list-style:none;padding:0;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin-top:22px}.learn-pathway a{display:flex;align-items:center;gap:12px;min-height:66px;padding:14px;border:1px solid var(--learn-edge);border-radius:7px;font-size:15px;line-height:1.4}.learn-pathway a:hover{border-color:var(--learn-accent)}.learn-pathway a span{color:var(--learn-accent);font-size:12px}.learn-pathway-next{max-width:790px;margin:28px auto 42px;padding:20px 0;border-block:1px solid var(--learn-edge)}.learn-pathway-next p{font-size:12px;color:var(--learn-soft);margin-bottom:15px}.learn-pathway-next div{display:flex;justify-content:space-between;gap:30px}.learn-pathway-next a{color:var(--learn-accent);font-size:15px;line-height:1.5;min-height:44px;max-width:50%;padding:8px 0}.learn-evidence-brief{border-left:2px solid #d8bd78;background:#1a2332;padding:17px 20px;margin:26px 0;border-radius:0 7px 7px 0}.learn-evidence-brief span{display:block;font-size:11px;color:var(--learn-soft);letter-spacing:.035em;margin-bottom:8px}.learn-evidence-brief strong{display:block;font-size:15px;font-weight:500;color:#efd58f;line-height:1.45}.learn-evidence-brief p{font-size:14px;line-height:1.6;color:var(--learn-copy);margin-top:9px}.learn-optimisation{padding:18px}.optimisation-picture{width:100%}.optimisation-picture svg{display:block;width:100%;height:auto;max-height:none}.optimisation-picture svg text{font:16px 'Helvetica Neue',Arial,sans-serif;fill:var(--learn-light)}.optimisation-picture svg .opt-small{font-size:12px;fill:var(--learn-copy)}.opt-node{fill:#152b41;stroke:#537797;stroke-width:1.5}.opt-node.active{stroke:var(--learn-accent);fill:#233e55}.opt-wire{stroke:#54728d;stroke-width:2;fill:none}.opt-wire.active{stroke:var(--learn-accent)}.optimisation-caption{font-size:16px;line-height:1.6;color:var(--learn-copy);margin-top:12px}.learn-optimisation .learn-controls{margin-top:15px}.learn-optimisation .learn-figure-note{font-size:12px;line-height:1.55;margin-top:18px}
@media(max-width:780px){.learn-pathway ol{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:480px){.learn-pathway{padding:20px}.learn-pathway ol{grid-template-columns:1fr}.learn-pathway-next div{flex-direction:column;gap:7px}.learn-pathway-next a{max-width:100%}.learn-optimisation{padding:12px}.optimisation-picture svg text{font-size:14px}.optimisation-picture svg .opt-small{font-size:11px}.learn-evidence-brief{padding:15px}.learn-optimisation .learn-controls button{font-size:13px}}