/* Approved article baseline. Theme-specific compositions build on the reading system. */
body.atlas-edition{--bg:#f4f7f8;--panel:#fff;--text:#142d3a;--muted:#526672;--accent:#087394;--line:#cedde3;background:var(--bg);color:var(--text);font-family:Meiryo,'Hiragino Kaku Gothic ProN',sans-serif;font-size:18px;line-height:1.9;color-scheme:light;}
.atlas-edition .shell{max-width:1300px;padding-left:48px;padding-right:48px;}
.atlas-edition .site-header{background:#102b3a;border-color:#284654;position:relative;color:#edf6fa;}
.atlas-edition .header-inner{min-height:82px;}
.atlas-edition .brand{font-size:23px;color:#fff;letter-spacing:.05em;}
.atlas-edition .brand small{font-size:11px;color:#c0d2dc;}
.atlas-edition .brand-mark{border-color:#bfdfe8;}
.atlas-edition .site-header nav{font-size:15px;gap:25px;}
.atlas-edition .nav-search{border-color:#486270;}
.atlas-edition .world-menu{--accent:#c2e9f4;--text:#fff;--muted:#c3d4db;}
.atlas-edition .world-menu summary{font-size:15px;background:#193f50;border-color:#547381;color:#fff;}
.atlas-edition .world-menu nav{background:#163749;border-color:#547381;}
.atlas-edition .world-menu nav a{color:#fff;}
.atlas-edition .world-menu nav a:hover{background:#294f60;}
.atlas-edition a:hover{color:#075673;}
.atlas-edition .site-header a:hover{color:#b8e8f4;}
.atlas-edition .breadcrumb{padding-top:26px;padding-bottom:0;font-size:14px;color:var(--muted);}
.polar-title{padding-top:32px;padding-bottom:26px;}
.polar-overline{font-size:14px;font-weight:700;letter-spacing:.08em;color:var(--accent);display:block;}
.polar-title h1{font-family:inherit;font-weight:700;font-size:clamp(38px,5vw,66px);letter-spacing:-.045em;line-height:1.32;margin:18px 0 22px;}
.polar-title h1 span{display:block;font-size:clamp(21px,2.4vw,32px);letter-spacing:.015em;font-weight:500;margin-top:14px;}
.polar-deck{font-size:20px;line-height:1.9;color:#3c5665;max-width:800px;}
.atlas-edition .article-dates{font-size:13px;gap:20px;color:var(--muted);margin-top:24px;}
.polar-cover .science-image{overflow:hidden;border:1px solid var(--line);border-radius:12px;background:#fff;}
.atlas-edition .science-image{margin:0;background:#fff;border:1px solid var(--line);border-radius:10px;overflow:hidden;}
.atlas-edition .science-image img{width:100%;height:auto;aspect-ratio:16/9;object-fit:contain;background:#0b1b29;}
.atlas-edition .science-image figcaption{padding:26px 30px;background:#fff;color:var(--text);font-size:16px;line-height:1.8;border:0;}
.atlas-edition .science-image figcaption p{font-size:16px;color:#253e4d;margin:15px 0 12px;}
.atlas-edition .science-image figcaption small{font-size:14px;line-height:1.85;color:var(--muted);display:block;}
.atlas-edition .image-badges{display:flex;flex-wrap:wrap;align-items:center;gap:10px;font-size:14px;color:#365766;border:0;padding:0;}
.atlas-edition .image-badges span{padding:0;border:0;font-size:14px;}
.atlas-edition .image-badges span:first-child{background:#e4f1f5;color:#075775;border-radius:4px;padding:5px 10px;font-weight:700;}
.atlas-edition .image-credit{margin-top:12px;}
.atlas-edition .image-sources{display:flex;flex-wrap:wrap;gap:6px 16px;margin-top:18px;padding-top:15px;border-top:1px solid #dce6eb;font-size:14px;line-height:1.8;}
.atlas-edition .image-sources>span{font-size:14px;width:100%;color:var(--muted);}
.atlas-edition .source-reference{overflow-wrap:anywhere;}
.polar-introduction{padding-top:56px;padding-bottom:24px;}
.atlas-edition .answer-box{background:none;border:0;padding:0;max-width:900px;}
.atlas-edition .answer-box h2{font-family:inherit;font-size:clamp(26px,3vw,36px);font-weight:700;line-height:1.6;margin:14px 0 18px;}
.atlas-edition .answer-box p{font-size:18px;line-height:1.95;color:var(--text);}
.atlas-edition .conditions-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:30px 0 24px;border:0;}
.atlas-edition .conditions-grid>div{background:#e8f0f3;border:0!important;padding:24px 28px;border-radius:8px;}
.atlas-edition .conditions-grid dt{font-size:14px;font-weight:700;color:#4e6573;margin-bottom:7px;}
.atlas-edition .conditions-grid dd{margin:0;}
.atlas-edition .conditions-grid strong{font-family:inherit;font-size:22px;font-weight:700;line-height:1.6;color:#143c50;}
.atlas-edition .conditions-grid small{font-size:15px;line-height:1.9;margin-top:10px;color:#3c5664;}
.atlas-edition .journey-nav{position:static;align-self:auto;margin:16px auto 70px;padding-top:32px;padding-bottom:30px;border-top:2px solid #b6ced8;}
.polar-index-heading{display:flex;align-items:baseline;flex-wrap:wrap;gap:12px 24px;margin-bottom:22px;}
.polar-index-heading h2{font-size:23px;font-family:inherit;font-weight:700;}
.atlas-edition .journey-nav nav{display:grid;grid-template-columns:1fr 1fr;gap:10px 22px;margin:0;border:0;}
.atlas-edition .journey-nav nav a{display:flex;align-items:flex-start;gap:16px;border:1px solid #c9dce4;border-radius:6px;padding:16px 18px;min-height:64px;font-size:16px;color:#173f51;background:#fff;transition:background .15s,border-color .15s;}
.atlas-edition .journey-nav nav a:hover,.atlas-edition .journey-nav nav a.current{background:#e4f2f7;border-color:#78a9bc;color:#075b7a;}
.atlas-edition .journey-nav nav a>span:first-child{font-family:var(--mono);font-size:20px;font-weight:700;color:#16779a;min-width:28px;line-height:1.5;}
.atlas-edition .journey-nav nav small{display:block;font-size:13px;line-height:1.7;margin-top:5px;color:#526a78;}
.polar-article{font-size:18px;line-height:1.95;}
.polar-prose{max-width:828px;margin-left:auto;margin-right:auto;padding-left:24px;padding-right:24px;}
.polar-figure-wrap{max-width:1100px;margin:32px auto;padding-left:24px;padding-right:24px;}
.atlas-edition .journey-stop{margin-bottom:76px;scroll-margin-top:30px;}
.atlas-edition .stop-kicker{border:0;padding:0;margin-bottom:16px;display:flex;align-items:center;gap:18px;color:#466b7e;font-size:14px;line-height:1.6;letter-spacing:0;}
.atlas-edition .stop-kicker>span:first-child{display:grid;place-items:center;background:#123f55;color:#fff;border-radius:50%;width:48px;height:48px;flex:none;font-size:21px;}
.atlas-edition .journey-stop h2{font-family:inherit;font-size:clamp(27px,3vw,36px);line-height:1.65;font-weight:700;letter-spacing:-.02em;margin:0 0 26px;color:#143548;}
.atlas-edition .journey-stop p{color:#223c4b;font-size:18px;line-height:1.95;}
.atlas-edition .journey-stop p+p{margin-top:24px;}
.atlas-edition .chapter-sources{margin:26px 0 12px;padding:0;background:#eaf0f3;border-radius:6px;}
.atlas-edition .chapter-sources summary{padding:12px 18px;font-size:15px;color:#315c71;min-height:48px;cursor:pointer;}
.atlas-edition .chapter-sources .source-inline{font-size:14px;line-height:1.85;display:flex;flex-direction:column;padding:0 18px 16px;gap:8px;margin:0;}
.atlas-edition .chapter-navigation{font-size:15px;border-top:1px solid #c9dce4;margin-top:26px;padding-top:18px;gap:18px;}
.atlas-edition .chapter-navigation small{font-size:13px;}
.atlas-edition .chapter-navigation a{min-height:48px;line-height:1.75;color:#0c6c8d;}
.atlas-edition .ice-section{border:1px solid #bdd1dc;border-radius:10px;background:#fff;padding:30px;}
.atlas-edition .ice-section>figcaption{font:700 25px/1.7 Meiryo,sans-serif;color:#193d51;margin-bottom:24px;}
.atlas-edition .ice-bed-model{border-color:#b7d1de;background:#e6f3f9;}
.atlas-edition .ice-body{background:linear-gradient(#dceff8,#a4d2e8);color:#173e54;}
.atlas-edition .ice-rock{color:#fff;background:#556571;}
.atlas-edition .ice-surface-label,.atlas-edition .radar-label,.atlas-edition .basal-label,.atlas-edition .ice-body>span,.atlas-edition .ice-rock>span{font-size:16px;font-family:inherit;color:#123c53;}
.atlas-edition .ice-rock>span{color:#fff;}
.atlas-edition .radar-path{border-color:#174e70;}
.atlas-edition .basal-water{background:#2787b2;}
.atlas-edition .ice-reading-key{gap:20px;margin-top:24px;}
.atlas-edition .ice-reading-key>div{padding:18px 22px;background:#edf4f7;border-radius:6px;}
.atlas-edition .ice-reading-key dt{font-size:17px;font-weight:700;color:#184c65;}
.atlas-edition .ice-reading-key dd{font-size:16px;color:#355264;margin:8px 0 0;line-height:1.9;}
.atlas-edition .ice-section-note{font-size:15px!important;color:#506575!important;}
.atlas-edition .ice-section .source-inline{font-size:14px!important;display:flex;flex-wrap:wrap;gap:6px 16px;}
.atlas-edition .measurement-figure{border:1px solid #bdd1dc;border-radius:10px;background:#fff;padding:30px;margin:0;}
.atlas-edition .measurement-figure>figcaption{font:700 25px/1.65 Meiryo,sans-serif;color:#193d51;margin-bottom:22px;}
.atlas-edition .measurement-table{width:100%;border-collapse:collapse;margin:0;border:0;font-size:16px;}
.atlas-edition .measurement-table caption{text-align:left;font-size:15px;color:#526a78;padding:0 0 20px;}
.atlas-edition .measurement-table thead th{background:#19445a;color:#fff;font-size:16px;text-align:left;padding:17px 22px;border:0;}
.atlas-edition .measurement-table tbody th,.atlas-edition .measurement-table tbody td{padding:24px 22px;border:0;border-bottom:1px solid #cedee6;vertical-align:top;color:#213f51;font-size:17px;line-height:1.85;}
.atlas-edition .measurement-table tbody th{width:36%;background:#edf4f7;font-weight:700;}
.atlas-edition .measurement-table tbody td{background:#fff;}
.atlas-edition .measurement-table tbody p{font-size:17px;margin:0;line-height:1.85;}
.atlas-edition .measurement-table tbody small{display:block;font-size:15px;color:#506a79;line-height:1.85;margin-top:12px;}
.atlas-edition .measurement-note{font-size:15px!important;line-height:1.85;color:#506575!important;}
.atlas-edition .measurement-sources{font-size:14px!important;line-height:1.85;display:flex;flex-wrap:wrap;gap:8px 14px;}
.atlas-edition .evidence-section{margin-top:70px;margin-bottom:60px;scroll-margin-top:30px;}
.atlas-edition .evidence-section h2{font:700 32px/1.6 Meiryo,sans-serif;margin:12px 0 16px;}
.evidence-intro{font-size:18px;max-width:750px;margin-bottom:26px;}
.atlas-edition .evidence-grid{grid-template-columns:1fr 1fr;gap:20px;}
.atlas-edition .evidence-grid>div{background:#fff;border:1px solid #c4d8e2;border-top:4px solid #3688a1;border-radius:8px;padding:28px;}
.atlas-edition .evidence-grid>div+div{border-top-color:#6b7793;}
.atlas-edition .evidence-grid h3,.atlas-edition .unknown-box h3{font-size:19px;line-height:1.7;color:#203e50;}
.atlas-edition .evidence-grid ul,.atlas-edition .unknown-box ul{font-size:16px;line-height:1.9;color:#3b5363;padding-left:22px;}
.atlas-edition .unknown-box{background:#e9f0f3;border:0;border-radius:8px;padding:28px;margin-top:20px;}
.atlas-edition .sources-section{border:0;padding-top:25px;margin-bottom:80px;font-size:16px;}
.atlas-edition .sources-section>h2{font:700 32px/1.6 Meiryo,sans-serif;margin:12px 0 18px;}
.atlas-edition .sources-section li{padding:24px 0;scroll-margin-top:24px;}
.atlas-edition .sources-section li>a{font-size:17px;line-height:1.75;font-weight:700;overflow-wrap:anywhere;}
.atlas-edition .source-id{display:block;color:#526775;font-size:13px;margin-bottom:8px;}
.atlas-edition .sources-section small{font-size:15px;line-height:1.9;margin-top:12px;}
.atlas-edition .source-return{font-size:14px;gap:8px 15px;margin-top:16px;}
.atlas-edition .source-return>span{font-size:14px;color:#526a78;}
.atlas-edition .source-return a{font-size:14px;line-height:1.7;min-height:44px;}
.atlas-edition .text-link{font-size:16px;}
.atlas-edition .reading-next{padding-top:50px;padding-bottom:48px;background:#e3eef3;border-top:1px solid #c5dae5;border-bottom:1px solid #c5dae5;}
.atlas-edition .reading-next h2{font:700 30px/1.6 Meiryo,sans-serif;}
.atlas-edition .reading-next .eyebrow{font-size:14px;}
.atlas-edition .sequence-nav{border-color:#a7c2d0;}
.atlas-edition .sequence-overview,.atlas-edition .sequence-link{padding:22px;}
.atlas-edition .sequence-nav strong{font-size:20px;color:#163f55;}
.atlas-edition .sequence-nav span,.atlas-edition .sequence-nav small{font-size:14px;}
.atlas-edition .next-question h3{font-size:24px;line-height:1.6;}
.atlas-edition .next-question p,.atlas-edition .next-question li a>span{font-size:16px;line-height:1.85;color:#3d5969;}
.atlas-edition .next-question li a strong{font-size:17px;color:#1a5470;}
.atlas-edition .next-question li a{padding:18px 0;}
.atlas-edition .other-reading-paths{font-size:15px;}
.atlas-edition .other-reading-paths a{font-size:15px;line-height:1.8;}
.polar-related{padding-top:62px;padding-bottom:64px;}
.atlas-edition .section-heading h2{font:700 30px/1.6 Meiryo,sans-serif;}
.atlas-edition .section-heading:before{display:none;}
.atlas-edition .world-card{border:1px solid #cbdce4;border-radius:9px;overflow:hidden;background:#fff;}
.atlas-edition .card-copy{padding:22px;}
.atlas-edition .card-copy h3{font-size:21px;font-family:inherit;line-height:1.65;color:#183e54;}
.atlas-edition .card-copy p{font-size:15px;line-height:1.9;color:#435c6b;}
.atlas-edition .card-copy .eyebrow,.atlas-edition .card-meta{font-size:13px;}
.atlas-edition footer{--text:#edf5f8;--muted:#c0d2dc;--accent:#a5d8e9;background:#112f40;color:#edf5f8;border-top:0;}
.atlas-edition footer a:hover{color:#bae8f4;}
.atlas-edition footer p,.atlas-edition footer nav a{font-size:15px;}
.atlas-edition footer small{font-size:13px;}
@media(max-width:1100px){.atlas-edition .shell{padding-left:32px;padding-right:32px;}.atlas-edition .header-inner{flex-wrap:wrap;padding-top:16px;padding-bottom:16px;}.atlas-edition .site-header nav{gap:18px;}.atlas-edition .world-grid{gap:20px;}}
@media(max-width:700px){
 .atlas-edition .shell{padding-left:22px;padding-right:22px;}.atlas-edition .header-inner{gap:14px;}.atlas-edition .brand{font-size:19px;}.atlas-edition .brand small{font-size:10px;}.atlas-edition .site-header nav{font-size:14px;gap:16px;}.atlas-edition .world-menu summary{font-size:14px;padding:8px 12px;}.atlas-edition .breadcrumb{font-size:13px;padding-top:20px;}
 .polar-title{padding-top:28px;padding-bottom:26px;}.polar-title h1{font-size:38px;margin:14px 0 18px;}.polar-title h1 span{font-size:22px;line-height:1.6;}.polar-deck{font-size:17px;line-height:1.85;}.wide-only{display:none;}.atlas-edition .article-dates{font-size:12px;gap:6px;flex-direction:column;}
 .atlas-edition .science-image figcaption{padding:20px;}.atlas-edition .science-image figcaption p{font-size:15px;}.atlas-edition .science-image figcaption small,.atlas-edition .image-sources,.atlas-edition .image-sources>span{font-size:14px;}
 .polar-introduction{padding-top:36px;padding-bottom:12px;}.atlas-edition .answer-box h2{font-size:26px;}.atlas-edition .answer-box p{font-size:17px;}.atlas-edition .conditions-grid{grid-template-columns:1fr;gap:10px;margin:26px 0 18px;}.atlas-edition .conditions-grid>div{padding:20px 22px;}.atlas-edition .conditions-grid strong{font-size:21px;}
 .atlas-edition .journey-nav{margin-bottom:48px;padding-top:26px;padding-bottom:12px;}.polar-index-heading h2{font-size:21px;}.atlas-edition .journey-nav nav{grid-template-columns:1fr;gap:8px;}.atlas-edition .journey-nav nav a{padding:14px 16px;font-size:15px;}.atlas-edition .journey-nav nav small{font-size:13px;}
 .polar-prose,.polar-figure-wrap{padding-left:22px;padding-right:22px;}.atlas-edition .journey-stop{margin-bottom:52px;}.atlas-edition .journey-stop h2{font-size:27px;margin-bottom:22px;}.atlas-edition .journey-stop p{font-size:17px;line-height:1.95;}.atlas-edition .stop-kicker{font-size:13px;gap:12px;}.atlas-edition .stop-kicker>span:first-child{width:42px;height:42px;font-size:19px;}
 .atlas-edition .chapter-navigation{flex-direction:column;align-items:flex-start;font-size:15px;}.atlas-edition .chapter-navigation a:last-child{text-align:left;max-width:none;}.atlas-edition .ice-section,.atlas-edition .measurement-figure{padding:20px 18px;}.atlas-edition .ice-section>figcaption,.atlas-edition .measurement-figure>figcaption{font-size:22px;line-height:1.7;}
 .atlas-edition .ice-reading-key{grid-template-columns:1fr;}.atlas-edition .ice-reading-key>div{padding:18px;}.atlas-edition .ice-reading-key dt{font-size:17px;}.atlas-edition .ice-reading-key dd{font-size:15px;}.atlas-edition .ice-surface-label,.atlas-edition .radar-label,.atlas-edition .basal-label,.atlas-edition .ice-body>span,.atlas-edition .ice-rock>span{font-size:14px;}
 .atlas-edition .measurement-table,.atlas-edition .measurement-table tbody{display:block;}.atlas-edition .measurement-table thead{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);}.atlas-edition .measurement-table tbody tr{display:block;border:1px solid #c6dbe5;border-radius:6px;margin-bottom:14px;padding:0;overflow:hidden;}.atlas-edition .measurement-table tbody th,.atlas-edition .measurement-table tbody td{display:block;width:auto;border:0;padding:18px;font-size:17px;}.atlas-edition .measurement-table tbody td{padding-top:16px;}.atlas-edition .measurement-table tbody p,.atlas-edition .measurement-table tbody small{font-size:15px;line-height:1.9;}.atlas-edition .mobile-table-label{font-size:13px;font-weight:700;color:#526a78;margin-bottom:10px;}
 .atlas-edition .evidence-section{margin-top:40px;}.atlas-edition .evidence-section h2,.atlas-edition .sources-section>h2{font-size:27px;}.atlas-edition .evidence-grid{grid-template-columns:1fr;}.atlas-edition .evidence-grid>div,.atlas-edition .unknown-box{padding:22px;}.evidence-intro{font-size:17px;}.atlas-edition .sources-section li>a{font-size:16px;}.atlas-edition .sources-section small{font-size:14px;}.atlas-edition .sources-section{margin-bottom:48px;}
 .atlas-edition .reading-next h2,.atlas-edition .section-heading h2{font-size:26px;}.atlas-edition .sequence-nav{grid-template-columns:1fr;}.atlas-edition .next-question{grid-template-columns:1fr;gap:20px;}.atlas-edition .next-question h3{font-size:22px;}.atlas-edition .world-grid{grid-template-columns:1fr;}.atlas-edition .card-copy{padding:22px;}.atlas-edition .card-copy h3{font-size:21px;}
}
@media(prefers-reduced-motion:reduce){.atlas-edition *, .atlas-edition *:before,.atlas-edition *:after{animation:none!important;transition:none!important;}}

.polar-cover-label{display:flex;flex-wrap:wrap;gap:4px 18px;align-items:center;font-size:14px;font-weight:700;color:#24566c;margin:0 0 12px;}
.polar-cover-label span{font-size:13px;font-weight:400;color:#526672;}
.atlas-edition .ice-bed-model{height:320px;border:1px solid #b7d1de;border-radius:6px;}
.atlas-edition .ice-body{inset:52px 0 82px;background:linear-gradient(#eef8fc,#b8deed);}
.atlas-edition .ice-body>span:first-child{top:32px;left:24px;font-size:24px;font-weight:700;}
.atlas-edition .ice-rock{height:82px;clip-path:polygon(0 0,30% 0,38% 24%,58% 24%,66% 0,100% 0,100% 100%,0 100%);}
.atlas-edition .basal-water{bottom:62px;left:30%;width:36%;height:20px;clip-path:polygon(0 0,100% 0,78% 100%,22% 100%);}
.atlas-edition .basal-label{bottom:104px;left:22%;font-weight:700;}
.atlas-edition .radar-path{top:0;bottom:0;right:16%;width:22px;}
.atlas-edition .radar-path:before,.atlas-edition .radar-path:after{content:'';position:absolute;border:6px solid transparent;}
.atlas-edition .radar-path:before{bottom:0;left:-7px;border-top-color:#174e70;}
.atlas-edition .radar-path:after{top:0;right:-7px;border-bottom-color:#174e70;}
.atlas-edition .radar-label{writing-mode:horizontal-tb;top:20px;right:3%;padding:7px 12px;background:#fff;border:1px solid #b7d1de;border-radius:4px;font-size:15px;}
@media(max-width:700px){.atlas-edition .ice-bed-model{height:290px;}.atlas-edition .ice-surface-label{top:12px;left:14px;}.atlas-edition .radar-label{top:62px;right:10px;font-size:14px;padding:6px 8px;}.atlas-edition .ice-body>span:first-child{top:72px;left:18px;font-size:22px;}.atlas-edition .basal-label{bottom:96px;left:18px;font-size:14px;}.atlas-edition .radar-path{right:12%;}}
.atlas-edition .sequence-overview,.atlas-edition .sequence-link{background:#fff;}.atlas-edition .sequence-link:hover{background:#edf7fa;}

.atlas-edition .source-inline .source-reference,.atlas-edition .measurement-sources .source-reference,.atlas-edition .image-sources .source-reference{font-size:14px;line-height:1.85;}
.atlas-edition .source-reference>span,.atlas-edition .source-id{display:none;}

/* Integrated polar opening: image, typography and reading route share one composition. */
.atlas-edition .polar-hero{position:relative;isolation:isolate;min-height:740px;overflow:hidden;background:#eaf2f6;border-bottom:1px solid #c4d7e1;}
.atlas-edition .polar-hero-visual.science-image{position:absolute;inset:0;border:0;border-radius:0;background:#dce8ef;}
.atlas-edition .polar-hero-visual img{width:100%;height:100%;aspect-ratio:auto;object-fit:cover;object-position:60% 58%;}
.atlas-edition .polar-hero-visual:after{content:'';position:absolute;inset:0;background:linear-gradient(90deg,#f1f7faed 0%,#f1f7fae0 26%,#f1f7fa85 48%,#f1f7fa00 72%);pointer-events:none;}
.atlas-edition .polar-hero-visual figcaption{position:absolute;bottom:26px;right:36px;z-index:2;display:flex;gap:12px;background:#163344e8;color:#fff;font-size:14px;line-height:1.6;padding:9px 14px;border-radius:0;}
.atlas-edition .polar-hero-visual figcaption span{color:#d6e7ef;font-size:14px;}
.atlas-edition .polar-title{position:relative;z-index:2;padding-top:30px;padding-bottom:64px;}
.polar-breadcrumb{font-size:13px;color:#3c5d6e;margin-bottom:58px;display:flex;gap:10px;}
.atlas-edition .polar-title .polar-overline{font-size:14px;letter-spacing:.15em;margin:0 0 22px;display:flex;align-items:center;gap:14px;color:#1b617d;}
.atlas-edition .polar-title .polar-overline:before{content:'';width:36px;height:2px;background:#1b617d;}
.atlas-edition .polar-title h1{font-size:clamp(48px,5vw,76px);line-height:1.22;font-weight:700;letter-spacing:-.055em;margin:0 0 28px;color:#123548;max-width:760px;}
.atlas-edition .polar-title h1 span{font-family:var(--serif);font-size:clamp(26px,2.65vw,39px);font-weight:500;line-height:1.65;letter-spacing:.035em;margin-top:19px;}
.atlas-edition .polar-deck{font-size:17px;line-height:1.95;max-width:570px;color:#284f62;margin:0;}
.polar-hero-actions{display:flex;align-items:center;flex-wrap:wrap;gap:22px;margin-top:30px;}
.atlas-edition .polar-start{display:inline-flex;gap:36px;align-items:center;justify-content:space-between;min-height:54px;padding:12px 22px;background:#173e53;color:#fff;border:1px solid #173e53;font-size:15px;transition:background .18s;}
.atlas-edition .polar-start:hover{background:#075977;color:#fff;}
.polar-start span{font-size:21px;}
.atlas-edition .polar-index-link{font-size:14px;min-height:44px;display:inline-flex;align-items:center;gap:18px;color:#214d62;border-bottom:1px solid #688c9e;}
.atlas-edition .polar-index-link:hover{color:#075673;border-color:#075673;}
.polar-hero-meta{padding-top:25px;padding-bottom:20px;border-bottom:1px solid #d0dfe6;}
.atlas-edition .polar-hero-meta .article-dates{margin:0;padding:0;border:0;}
.polar-hero-notes{font-size:14px;margin-top:14px;color:#526672;max-width:800px;}
.polar-hero-notes summary{cursor:pointer;min-height:44px;display:list-item;width:fit-content;line-height:44px;color:#305e74;}
.polar-hero-notes p{font-size:14px;line-height:1.85;margin:8px 0;}
.polar-hero-notes .image-sources{margin-top:12px;padding-top:10px;}
@media(min-width:1800px){.atlas-edition .polar-hero-visual img{object-position:60% 70%;}.atlas-edition .polar-hero{min-height:800px;}}
@media(max-width:700px){
 .atlas-edition .polar-hero{display:flex;flex-direction:column;min-height:0;}
 .atlas-edition .polar-title{order:0;width:100%;padding-top:18px;padding-bottom:0;}
 .polar-breadcrumb{margin-bottom:28px;font-size:12px;}
 .atlas-edition .polar-title .polar-overline{font-size:12px;margin-bottom:16px;}
 .atlas-edition .polar-title h1{font-size:clamp(32px,9.5vw,43px);margin-bottom:20px;letter-spacing:-.05em;}
 .atlas-edition .polar-title h1 span{font-size:25px;line-height:1.5;margin-top:15px;}
 .atlas-edition .polar-title h1 span br{display:none;}
 .atlas-edition .polar-deck{font-size:15px;line-height:1.95;}
 .polar-hero-actions{gap:18px;margin-top:22px;}
 .atlas-edition .polar-start{font-size:14px;gap:22px;padding:10px 16px;min-height:50px;}
 .atlas-edition .polar-index-link{font-size:13px;gap:10px;}
 .atlas-edition .polar-hero-visual.science-image{position:relative;order:1;inset:auto;height:340px;flex:none;margin-top:8px;}
 .atlas-edition .polar-hero-visual img{object-position:52% 65%;}
 .atlas-edition .polar-hero-visual:after{background:linear-gradient(#eaf2f6 0%,#eaf2f680 10%,#eaf2f600 26%);}
 .atlas-edition .polar-hero-visual figcaption{right:14px;bottom:15px;padding:7px 10px;font-size:14px;gap:9px;}
 .atlas-edition .polar-hero-visual figcaption span{font-size:14px;}
 .polar-hero-meta{padding-top:20px;padding-bottom:16px;}
}

.atlas-edition .polar-start{max-width:100%;}.atlas-edition .polar-hero-visual figcaption{max-width:calc(100% - 28px);flex-wrap:wrap;}

/* Each environment keeps its own material and lighting; prose stays on readable paper. */
.atlas-edition.theme-underground{--bg:#f7f4ef;--accent:#745036;--muted:#675b50;}
.atlas-edition.theme-underground .polar-hero{background:#ece7df;}
.atlas-edition.theme-underground .polar-hero-visual:after{background:linear-gradient(90deg,#f7f4eff5 0%,#f7f4efe6 28%,#f7f4ef80 48%,transparent 72%);}
.atlas-edition.theme-underground .polar-title h1{color:#3a3028;}
.atlas-edition.theme-underground .polar-overline{color:#72513b;}
.atlas-edition.theme-underground .polar-key{color:#754923;background:linear-gradient(transparent 72%,#eddec8 72%);}
.atlas-edition.theme-underground .conditions-grid>div{background:#eee7dd;border-left-color:#b89a76!important;}
.atlas-edition.theme-underground .stop-kicker>span:first-child{background:#614933;}
.atlas-edition.theme-deep-sea{--bg:#f1f6f7;}
.atlas-edition.theme-space{--bg:#f4f5f8;}
.atlas-edition.theme-deep-sea .polar-hero,.atlas-edition.theme-space .polar-hero{background:#081924;border-color:#29404f;}
.atlas-edition.theme-deep-sea .polar-hero-visual,.atlas-edition.theme-space .polar-hero-visual{background:#081924;}
.atlas-edition.theme-deep-sea .polar-hero-visual:after{background:linear-gradient(90deg,#081924f5 0%,#081924e8 26%,#08192490 47%,#08192415 72%);}
.atlas-edition.theme-space .polar-hero-visual:after{background:linear-gradient(90deg,#081924 0%,#081924e8 27%,#08192440 51%,transparent 70%);}
.atlas-edition.theme-space .polar-hero-visual img{width:75%;margin-left:25%;object-fit:contain;background:#081924;}
.atlas-edition.theme-space .polar-hero-visual img{mask-image:linear-gradient(90deg,transparent,#000 30%,#000 75%,transparent);}
.atlas-edition.theme-space .polar-title h1,.atlas-edition.theme-deep-sea .polar-title h1{color:#f2f7f9;}
.atlas-edition.theme-space .polar-deck,.atlas-edition.theme-deep-sea .polar-deck{color:#d4e1e8;}
.atlas-edition.theme-space .polar-breadcrumb,.atlas-edition.theme-deep-sea .polar-breadcrumb{color:#c4dce6;}
.atlas-edition.theme-space .polar-title .polar-overline,.atlas-edition.theme-deep-sea .polar-title .polar-overline{color:#9fdae8;}
.atlas-edition.theme-space .polar-title .polar-overline:before,.atlas-edition.theme-deep-sea .polar-title .polar-overline:before{background:#9fdae8;}
.atlas-edition.theme-space .polar-start,.atlas-edition.theme-deep-sea .polar-start{background:#d9eef3;color:#123c50;border-color:#d9eef3;}
.atlas-edition.theme-space .polar-start:hover,.atlas-edition.theme-deep-sea .polar-start:hover{background:#b7e1ec;}
.atlas-edition.theme-space .polar-index-link,.atlas-edition.theme-deep-sea .polar-index-link{color:#d4edf5;border-color:#8eaebd;}
.atlas-edition.theme-space .polar-hero a:hover,.atlas-edition.theme-deep-sea .polar-hero a:hover{color:#fff;}
.atlas-edition.theme-space .polar-start:hover,.atlas-edition.theme-deep-sea .polar-start:hover{color:#123c50;}
.atlas-edition .image-conditions{margin:15px 0;font-size:14px;}
.atlas-edition .image-conditions summary{font-size:14px;line-height:1.8;min-height:44px;padding:10px 0;color:#365b70;cursor:pointer;}
.atlas-edition .image-conditions small{padding:8px 0;}
.atlas-edition .earth-profile,.atlas-edition .atmosphere-diagram,.atlas-edition .storm-section,.atlas-edition .evidence-flow,.atlas-edition .comparison{background:#fff;border:1px solid #bfd2dd;border-radius:10px;padding:30px;margin:0;}
.atlas-edition .earth-profile>figcaption,.atlas-edition .atmosphere-diagram>figcaption,.atlas-edition .storm-section>figcaption,.atlas-edition .evidence-flow>figcaption,.atlas-edition .comparison h3{font:700 25px/1.7 Meiryo,sans-serif;color:#193d51;padding:0;}
.atlas-edition .earth-profile-key p{font-size:22px;color:#254556;}
.atlas-edition .earth-profile-key small{font-size:15px;color:#526672;}
.atlas-edition .earth-profile-key .eyebrow{font-size:14px;}
.atlas-edition .earth-profile table{font-size:17px;}
.atlas-edition .earth-profile table,.atlas-edition .earth-profile caption,.atlas-edition .earth-profile td{background:#fff;}
.atlas-edition .sequence-finish{background:#fff;padding:22px;}
.atlas-edition .earth-profile caption{font-size:15px;color:#526672;}
.atlas-edition .earth-profile th,.atlas-edition .earth-profile td{padding:22px;border-color:#cedde3;color:#213f51;}
.atlas-edition .earth-profile thead th{background:#19445a;color:#fff;}
.atlas-edition .earth-profile tbody th{background:#edf4f7;font-weight:700;}
.atlas-edition .earth-profile table small{font-size:15px;color:#506a79;line-height:1.9;}
.atlas-edition .earth-profile td strong{font-weight:700;}
.atlas-edition .earth-profile-note,.atlas-edition .atmosphere-diagram-note,.atlas-edition .evidence-flow>small,.atlas-edition .comparison>p{font-size:15px!important;line-height:1.95!important;color:#526672;}
.atlas-edition .water-state-grid>div{background:#edf4f7;border-color:#c2d7e1;padding:20px;}
.atlas-edition .water-state-grid h3{font-size:22px;font-family:inherit;font-weight:700;color:#18475f;}
.atlas-edition .water-state-grid p{font-size:16px;line-height:1.9;}
.atlas-edition .water-state{background:#e2eef4;border-color:#b3d0df;}
.atlas-edition .water-state.gas{background:linear-gradient(135deg,#e8f1f6,#d5e9f2);}
.atlas-edition .water-state.gas span{font-size:16px;color:#1b4d66;}
.atlas-edition .water-state.drops i{background:#237f9c;box-shadow:none;}
.atlas-edition .water-state.ice i{border-color:#286c91;}.atlas-edition .water-state.ice i:after{background:#286c91;}
.atlas-edition .cyclone-wall strong{font-size:16px;font-weight:700;}
.atlas-edition .cyclone-eye strong{font-size:19px;}.atlas-edition .cyclone-sea{font-size:15px;}
.atlas-edition .cyclone-key dt,.atlas-edition .storm-key dt{font-size:18px;font-weight:700;}
.atlas-edition .cyclone-key dd,.atlas-edition .storm-key dd{font-size:16px;line-height:1.95;color:#365264;}
.atlas-edition .storm-layout{padding:26px 0;}
.atlas-edition .storm-anvil,.atlas-edition .storm-base{font-size:15px;}
.atlas-edition .storm-columns strong,.atlas-edition .storm-charge strong{font-size:17px;}
.atlas-edition .storm-mixture i{font-size:15px;}
.atlas-edition .storm-up{color:#146479;}.atlas-edition .storm-down{color:#3e527d;}
.atlas-edition .storm-charge span{color:#354e75;}.atlas-edition .storm-charge>div:nth-child(2) span{color:#116679;}
.atlas-edition .storm-note,.atlas-edition .storm-sources{font-size:15px!important;line-height:1.95!important;padding:0;color:#526672;}
.atlas-edition .storm-sources .source-reference{font-size:14px;}
.atlas-edition .evidence-flow li{padding:22px 0;border-color:#cedde3;}
.atlas-edition .evidence-flow li>span{font-size:18px;}
.atlas-edition .evidence-flow strong{font-size:20px;color:#194f68;}
.atlas-edition .evidence-flow li p{font-size:17px;line-height:1.95;color:#365264;}
.atlas-edition .comparison>div{font-size:17px;grid-template-columns:130px minmax(0,1fr) 120px;}
.atlas-edition .comparison strong{font-size:16px;}.atlas-edition .comparison-track{background:#dce8ed;}.atlas-edition .comparison-track i{background:#368aa2;}
.atlas-edition .relief-comparison>section,.atlas-edition .pixel-example{background:#edf4f7;border-color:#c0d6e1;}
.atlas-edition .relief-comparison h3,.atlas-edition .pixel-explanation h3{font-size:20px;color:#1d4a60;}
.atlas-edition .relief-comparison p,.atlas-edition .pixel-explanation p{font-size:16px;line-height:1.9;color:#365264;}
.atlas-edition .relief-width-note,.atlas-edition .pixel-example>span{font-size:14px;color:#526672;}
.atlas-edition .pixel-value{font-size:16px;color:#24536b;}.atlas-edition .pixel-value strong{font-size:28px;}
@media(max-width:700px){
 .atlas-edition.theme-underground .polar-hero-visual:after{background:linear-gradient(#ece7df,transparent 28%);}
 .atlas-edition.theme-space .polar-hero-visual:after,.atlas-edition.theme-deep-sea .polar-hero-visual:after{background:linear-gradient(#081924,transparent 28%);}
 .atlas-edition.theme-space .polar-hero-visual img{width:100%;margin-left:0;object-fit:contain;}
 .atlas-edition.theme-space .polar-hero-visual img{mask-image:none;}
 .atlas-edition .polar-hero[data-article="earth-interior"] .polar-hero-visual img{object-position:86% 65%;}
 .atlas-edition .earth-profile,.atlas-edition .atmosphere-diagram,.atlas-edition .storm-section,.atlas-edition .evidence-flow,.atlas-edition .comparison{padding:20px 18px;}
 .atlas-edition .earth-profile>figcaption,.atlas-edition .atmosphere-diagram>figcaption,.atlas-edition .storm-section>figcaption,.atlas-edition .evidence-flow>figcaption{font-size:22px;}
 .atlas-edition .earth-profile table,.atlas-edition .earth-profile tbody{display:block;}
 .atlas-edition .earth-profile thead{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);}
 .atlas-edition .earth-profile tbody tr{display:block;border:1px solid #c6dbe5;border-radius:6px;margin-bottom:14px;overflow:hidden;}
 .atlas-edition .earth-profile tbody th,.atlas-edition .earth-profile tbody td{display:block;width:auto;border:0;padding:18px;font-size:17px;}
 .atlas-edition .water-state-grid{grid-template-columns:1fr;}.atlas-edition .water-state-grid p{font-size:16px;}
 .atlas-edition .cyclone-key,.atlas-edition .storm-layout{grid-template-columns:1fr;}
 .atlas-edition .cyclone-wall strong{font-size:14px;padding:6px;}.atlas-edition .cyclone-eye strong{font-size:17px;}
 .atlas-edition .comparison>div{grid-template-columns:1fr auto;gap:10px;font-size:16px;}.atlas-edition .comparison-track{grid-column:1/-1;grid-row:auto;}
 .atlas-edition .relief-comparison,.atlas-edition .pixel-comparison{grid-template-columns:1fr;}
}

/* Reading rhythm: Mincho chapter titles, a larger opening, selective semantic emphasis. */
.atlas-edition{--polar-reading-edition:typography-v1;}
.atlas-edition .polar-chapter-copy{max-width:800px;}
.atlas-edition .journey-stop h2,.atlas-edition .answer-box h2{font-family:var(--serif);font-weight:700;letter-spacing:.015em;line-height:1.55;text-wrap:balance;}
.atlas-edition .journey-stop h2{font-size:clamp(30px,3vw,38px);margin-bottom:30px;padding-bottom:22px;border-bottom:1px solid #bed1dc;}
.atlas-edition .polar-title-phrase{display:inline-block;max-width:100%;vertical-align:top;}
.atlas-edition .polar-chapter-copy>p{line-height:2.05;letter-spacing:.025em;color:#2d4654;text-wrap:pretty;}
.atlas-edition .polar-chapter-copy>p.polar-lead{font-size:20px;line-height:1.95;letter-spacing:.015em;color:#173b4e;margin-bottom:30px;}
.atlas-edition .polar-chapter-copy>p+p{margin-top:26px;}
.atlas-edition .polar-key{font-family:inherit;font-size:inherit;font-weight:700;color:#075c79;background:linear-gradient(transparent 72%,#d4e9ee 72%);padding:0 .04em;box-decoration-break:clone;-webkit-box-decoration-break:clone;}
.atlas-edition .answer-box{max-width:960px;}
.atlas-edition .answer-box h2{max-width:860px;font-size:clamp(28px,3vw,38px);margin-bottom:24px;}
.atlas-edition .answer-box>p{max-width:850px;line-height:2.05;letter-spacing:.02em;}
.atlas-edition .conditions-grid>div{position:relative;background:#e9f1f4;padding-top:26px;border-left:3px solid #7baabb!important;}
.atlas-edition .conditions-grid dt{letter-spacing:.09em;color:#426373;}
.atlas-edition .conditions-grid strong{font-size:23px;letter-spacing:.015em;}
.atlas-edition .stop-kicker{margin-bottom:22px;}
.atlas-edition .stop-kicker>span:last-child{font-weight:700;letter-spacing:.045em;}
.atlas-edition .evidence-grid h3{font-size:21px;letter-spacing:.01em;}
.atlas-edition .evidence-grid li+li,.atlas-edition .unknown-box li+li{margin-top:14px;}
.atlas-edition .evidence-grid li::marker{color:#087394;}
.atlas-edition .evidence-grid>div+div li::marker{color:#6b7793;}
.atlas-edition .science-image figcaption>p{font-weight:700;color:#173b4e;}
.atlas-edition .measurement-table tbody th{color:#124b64;}
.atlas-edition .measurement-table tbody small{padding-top:12px;border-top:1px solid #dce7ed;}
.atlas-edition .source-return a{color:#0c6381;}
@media(max-width:700px){
 .atlas-edition .journey-stop h2{font-size:29px;line-height:1.65;letter-spacing:.01em;margin-bottom:24px;padding-bottom:18px;}
 .atlas-edition .polar-chapter-copy>p{font-size:17px;line-height:2;letter-spacing:.015em;}
 .atlas-edition .polar-chapter-copy>p.polar-lead{font-size:18px;line-height:2;margin-bottom:24px;}
 .atlas-edition .polar-chapter-copy>p+p{margin-top:24px;}
 .atlas-edition .answer-box h2{font-size:28px;line-height:1.7;}
 .atlas-edition .answer-box>p{font-size:17px;line-height:2;}
 .atlas-edition .conditions-grid strong{font-size:22px;}
 .atlas-edition .evidence-grid h3{font-size:20px;}
}

/* Groundwater: a grain-scale spread; explanatory geometry, no measured scale. */
.atlas-edition .pore-figure{padding:36px;background:#f1eee6;border:1px solid #d0c6b5;color:#332e25;}
.atlas-edition .pore-figure figcaption{font-family:var(--serif);font-size:clamp(23px,2.5vw,31px);font-weight:700;line-height:1.6;}
.atlas-edition .pore-intro{max-width:740px;font-size:17px;line-height:1.9;margin:16px 0 20px;}
.atlas-edition .pore-legend{display:flex;flex-wrap:wrap;gap:12px 24px;font-size:14px;font-weight:700;}
.atlas-edition .pore-legend>span{display:flex;align-items:center;gap:9px;}
.atlas-edition .pore-legend i{display:block;width:18px;height:18px;flex:none;border:1px solid #7d6746;}
.atlas-edition .pore-key-grain{border-radius:50%;background:#a78b61;}
.atlas-edition .pore-legend .pore-key-water{background:#bad8df;border-color:#64858d;}
.atlas-edition .pore-models{list-style:none;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:28px;padding:0;margin:28px 0;}
.atlas-edition .pore-model-heading{display:flex;align-items:baseline;gap:12px;margin-bottom:16px;}
.atlas-edition .pore-model-heading>span{font:700 15px/1.5 var(--sans);color:#75603e;}
.atlas-edition .pore-model-heading h3{margin:0;font-size:18px;line-height:1.6;font-family:var(--serif);}
.atlas-edition .pore-plane{position:relative;aspect-ratio:2;background:#bad8df;border:1px solid #77949b;overflow:hidden;}
.atlas-edition .pore-grain{position:absolute;aspect-ratio:1;border-radius:50%;transform:translate(-50%,-50%);background:radial-gradient(circle at 35% 30%,#d4bd92,#a78b61 70%);border:1px solid #7d6746;}
.atlas-edition .pore-filler{background:#897251;}
.atlas-edition .pore-model-takeaway{display:block;font-size:18px;line-height:1.6;margin-top:18px;color:#4e3b1f;}
.atlas-edition .pore-models li>p{font-size:15px;line-height:1.9;margin:10px 0 0;}
.atlas-edition .pore-conclusion{border-top:2px solid #ac9879;padding-top:24px;}
.atlas-edition .pore-conclusion h3{font-family:var(--serif);font-size:22px;line-height:1.6;margin:0 0 12px;}
.atlas-edition .pore-conclusion p{font-size:17px;line-height:1.9;margin:0;}
.atlas-edition .pore-conclusion strong{color:#4e3b1f;}
.atlas-edition .pore-note,.atlas-edition .pore-sources{font-size:14px;line-height:1.9;margin:20px 0 0;}
.atlas-edition .pore-assumptions{border-top:1px solid #d0c6b5;margin-top:24px;padding-top:16px;font-size:15px;}
.atlas-edition .pore-assumptions summary{cursor:pointer;color:#4e3b1f;font-weight:700;}
.atlas-edition .pore-assumptions summary:focus-visible{outline:3px solid #087394;outline-offset:5px;}
.atlas-edition .pore-sources{display:flex;flex-wrap:wrap;gap:8px 16px;}
@media(max-width:900px){.atlas-edition .pore-models{grid-template-columns:1fr;gap:28px;}.atlas-edition .pore-models li{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);column-gap:24px;}.atlas-edition .pore-model-heading{grid-column:1/-1;}.atlas-edition .pore-plane{grid-row:2/4;}.atlas-edition .pore-model-takeaway{margin-top:0;}}
@media(max-width:600px){.atlas-edition .pore-figure{padding:22px 18px;}.atlas-edition .pore-models li{display:block;padding-bottom:24px;border-bottom:1px solid #d0c6b5;}.atlas-edition .pore-model-takeaway{margin-top:16px;}.atlas-edition .pore-conclusion h3{font-size:21px;}.atlas-edition .pore-models li>p{font-size:16px;}}

/* Grain study: warm paper and an enlarged observation field. */
.atlas-edition.theme-microscopic{--bg:#f7f3e8;--accent:#70512a;--muted:#625641;}
.atlas-edition.theme-microscopic .polar-hero{background:#eee6d5;border-color:#ccba98;}
.atlas-edition.theme-microscopic .polar-hero-visual{background:#eee6d5;}
.atlas-edition.theme-microscopic .polar-hero-visual img{width:62%;margin-left:38%;object-position:60% 45%;}
.atlas-edition.theme-microscopic .polar-hero-visual:after{background:linear-gradient(90deg,#f7f3e8 0%,#f7f3e8 32%,#f7f3e8e6 42%,#f7f3e820 65%,transparent 80%);}
.atlas-edition.theme-microscopic .polar-title h1{color:#463721;}
.atlas-edition.theme-microscopic .polar-title .polar-overline{color:#70512a;}
.atlas-edition.theme-microscopic .polar-deck{color:#4e422f;}
.atlas-edition.theme-microscopic .polar-key{color:#6e491f;background:linear-gradient(transparent 72%,#ead9b9 72%);}
.atlas-edition.theme-microscopic .conditions-grid>div{background:#eee5d3;border-left-color:#aa8a54!important;}
.atlas-edition.theme-microscopic .conditions-grid dt{color:#625031;}
.atlas-edition.theme-microscopic .conditions-grid strong{color:#4c3920;}
.atlas-edition.theme-microscopic .stop-kicker>span:first-child{background:#70512a;}
@media(max-width:700px){.atlas-edition.theme-microscopic .polar-hero-visual img{width:100%;margin-left:0;object-position:50% 50%;}.atlas-edition.theme-microscopic .polar-hero-visual:after{background:linear-gradient(#f7f3e8 0%,#f7f3e840 12%,transparent 30%);}.atlas-edition.theme-microscopic .polar-hero-visual figcaption{top:18px;bottom:auto;}}

/* Diatom plate: a quiet microscope field, distinct from the grain photograph. */
.atlas-edition .polar-cover[data-article=diatoms]{background:#eef0e9;border-color:#b9c2b2;}
.atlas-edition .polar-cover[data-article=diatoms] .polar-hero-visual{background:#eef0e9;}
.atlas-edition .polar-cover[data-article=diatoms] .polar-hero-visual img{width:72%;margin-left:28%;object-position:68% 45%;}
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.atlas-edition .polar-cover[data-article=diatoms] .polar-overline{color:#475a44;}
.atlas-edition .polar-cover[data-article=diatoms] h1{color:#334230;}
@media(max-width:700px){.atlas-edition .polar-cover[data-article=diatoms] .polar-hero-visual img{width:100%;margin-left:0;object-position:50% 48%;}.atlas-edition .polar-cover[data-article=diatoms] .polar-hero-visual:after{background:linear-gradient(#f7f3e8 0%,#f7f3e830 12%,transparent 32%);}}

/* Pollen: warm transmitted light and the circular eyepiece field. */
.atlas-edition .polar-cover[data-article=pollen-grains]{background:#f2e6cb;border-color:#c9b68c;}
.atlas-edition .polar-cover[data-article=pollen-grains] .polar-hero-visual{background:#f2e6cb;}
.atlas-edition .polar-cover[data-article=pollen-grains] .polar-hero-visual img{width:74%;margin-left:26%;object-position:62% 50%;}
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.atlas-edition .polar-cover[data-article=pollen-grains] .polar-overline{color:#76521d;}
.atlas-edition .polar-cover[data-article=pollen-grains] h1{color:#533b19;}
@media(max-width:700px){.atlas-edition .polar-cover[data-article=pollen-grains] .polar-hero-visual img{width:100%;margin-left:0;object-position:50% 50%;}.atlas-edition .polar-cover[data-article=pollen-grains] .polar-hero-visual:after{background:linear-gradient(#f7f3e8 0%,#f7f3e830 12%,transparent 30%);}}

/* Solar photosphere: a full disk beside the reading column; original frames remain in the article. */
.atlas-edition .polar-cover[data-article=sun-photosphere]{background:#05080c;border-color:#a57c3a;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-hero-visual{background:#05080c;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-hero-visual img{width:74%;margin-left:26%;object-fit:contain;object-position:center;background:#05080c;mask-image:none;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-hero-visual:after{background:linear-gradient(90deg,#05080c 0%,#05080cf0 28%,#05080c70 45%,transparent 62%);}
.atlas-edition .polar-cover[data-article=sun-photosphere] h1{color:#ffe0a2;}
.atlas-edition .polar-cover[data-article=sun-photosphere] h1 span{color:#fff3dc;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-overline{color:#f0c575;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-start{background:#ffdf99;color:#30220d;border-color:#ffdf99;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-start:hover{background:#fff0c9;color:#30220d;}
@media(max-width:700px){
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-hero-visual img{width:100%;margin-left:0;object-position:center;}
.atlas-edition .polar-cover[data-article=sun-photosphere] .polar-hero-visual:after{background:none;}
}

.solar-edition .measurement-table th,.solar-edition .measurement-table td,.solar-edition .measurement-table small{overflow-wrap:anywhere;}
.solar-edition .polar-key{color:#704513;background-color:#fff0cd;}

.solar-edition #layers .evidence-flow ol{border-left:4px solid #b87925;}
.solar-edition #layers .evidence-flow li{padding:22px 24px;border-top:0;border-bottom:1px solid #dfd6c5;background:#fff6e3;}
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.solar-edition #layers .evidence-flow strong{color:#503715;}
@media(max-width:700px){.solar-edition #layers .evidence-flow li{padding:20px 14px;}}

/* Earth: the curved, luminous atmosphere leads into the invisible magnetic field. */
.atlas-edition .polar-cover[data-article=earth-magnetic-field]{background:#061211;border-color:#4e8373;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-hero-visual{background:#061211;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-hero-visual img{width:83%;margin-left:17%;object-fit:cover;object-position:65% 50%;mask-image:none;}
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.atlas-edition .polar-cover[data-article=earth-magnetic-field] h1{color:#d3f5d9;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] h1 span{color:#f1fff8;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-overline{color:#b0dfc2;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-start{background:#d4f2df;color:#123c2c;border-color:#d4f2df;}
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@media(max-width:700px){
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-hero-visual img{width:100%;margin-left:0;object-fit:contain;object-position:center;}
.atlas-edition .polar-cover[data-article=earth-magnetic-field] .polar-hero-visual:after{background:none;}
}

.magnetic-edition .polar-key{color:#17513d;background-color:#e4f2e9;}
.magnetic-edition .measurement-table th,.magnetic-edition .measurement-table td,.magnetic-edition .measurement-table small{overflow-wrap:anywhere;}
.magnetic-edition #aurora .evidence-flow ol{border-left:4px solid #547e6a;}
.magnetic-edition #aurora .evidence-flow li{background:#edf5ef;padding:22px 24px;border-top:0;border-bottom:1px solid #cfdfd5;}
.magnetic-edition #aurora .evidence-flow li:nth-child(2){background:#f4f6f2;}
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.magnetic-edition #aurora .evidence-flow strong{color:#244b3b;}
@media(max-width:700px){.magnetic-edition #aurora .evidence-flow li{padding:20px 14px;}}

/* Nebula: a vertical observation rising beside the reading column. Full frames follow in the chapters. */
.atlas-edition .polar-cover[data-article=inside-nebula]{background:#05080c;border-color:#8d7152;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-hero-visual{background:#05080c;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-hero-visual img{width:90%;margin-left:20%;object-fit:cover;object-position:center;mask-image:none;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-hero-visual:after{background:linear-gradient(90deg,#05080c 0%,#05080c 30%,#05080cb0 46%,transparent 68%);}
.atlas-edition .polar-cover[data-article=inside-nebula] h1{color:#f7d9a8;}
.atlas-edition .polar-cover[data-article=inside-nebula] h1 span{color:#f4eee5;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-overline{color:#e5c291;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-start{background:#efd2a5;color:#30220f;border-color:#efd2a5;}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-start:hover{background:#fff0d5;color:#30220f;}
.nebula-edition .polar-key{color:#69461d;background-color:#f9edda;}
.nebula-edition .measurement-table th,.nebula-edition .measurement-table td,.nebula-edition .measurement-table small{overflow-wrap:anywhere;}
.nebula-edition #stars .evidence-flow ol{border-left:4px solid #977049;}
.nebula-edition #stars .evidence-flow li{padding:22px 24px;border-top:0;border-bottom:1px solid #d8d0c5;background:#faf1e3;}
.nebula-edition #stars .evidence-flow li:nth-child(2){background:#f3f2ee;}
.nebula-edition #stars .evidence-flow li:nth-child(3){background:#edf3f7;}
.nebula-edition #stars .evidence-flow strong{color:#54422b;}
@media(max-width:700px){
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-hero-visual img{width:100%;margin-left:0;object-fit:cover;transform:scale(1.35);}
.atlas-edition .polar-cover[data-article=inside-nebula] .polar-hero-visual:after{background:none;}
.nebula-edition #stars .evidence-flow li{padding:20px 14px;}
}

/* Black hole: a bent band of light against an open, dark reading field. */
.atlas-edition .polar-cover[data-article=near-black-hole]{background:#000000;border-color:#ba7a46;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-hero-visual{background:#000000;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-hero-visual img{width:88%;margin-left:22%;object-fit:contain;object-position:center;mask-image:none;background:#000000;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-hero-visual:after{background:linear-gradient(90deg,#000000 0%,#000000 26%,#000000dd 39%,#00000040 58%,transparent 78%);}
.atlas-edition .polar-cover[data-article=near-black-hole] h1{color:#ffd2a8;font-size:clamp(38px,4.4vw,64px);}
.atlas-edition .polar-cover[data-article=near-black-hole] h1 span{color:#fff1e5;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-overline{color:#edbf99;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-start{background:#f5d0aa;color:#3d2510;border-color:#f5d0aa;}
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-start:hover{background:#fff0dd;color:#3d2510;}
.black-hole-edition .polar-key{color:#744216;background-color:#faecd9;}
.black-hole-edition .measurement-table th,.black-hole-edition .measurement-table td,.black-hole-edition .measurement-table small{overflow-wrap:anywhere;}
.black-hole-edition #brightness .evidence-flow ol{border-left:4px solid #9e6539;}
.black-hole-edition #brightness .evidence-flow li{padding:22px 24px;border-top:0;border-bottom:1px solid #dfd0c2;background:#fbf0e3;}
.black-hole-edition #brightness .evidence-flow li:nth-child(2){background:#f7f1eb;}
.black-hole-edition #brightness .evidence-flow li:nth-child(3){background:#f0f4f7;}
.black-hole-edition #brightness .evidence-flow strong{color:#6b4220;}
@media(max-width:700px){
.atlas-edition .polar-cover[data-article=near-black-hole] .polar-hero-visual img{width:100%;margin-left:0;object-fit:contain;object-position:center;}
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.black-hole-edition #brightness .evidence-flow li{padding:20px 14px;}
}

@media(max-width:700px){.atlas-edition .polar-cover[data-article=near-black-hole] h1{font-size:clamp(30px,8.9vw,38px);}}
/* Communications beneath the ocean: quiet amber signals against deep blue water. */
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.atlas-edition .polar-cover[data-article=submarine-cables] h1 span{color:#fff3e1;}
.atlas-edition .polar-cover[data-article=submarine-cables] .polar-overline{color:#f6ce98;}
.atlas-edition .polar-cover[data-article=submarine-cables] .polar-start{background:#f4d3a6;color:#24313b;border-color:#f4d3a6;}
.atlas-edition .polar-cover[data-article=submarine-cables] .polar-start:hover{background:#fff0d8;}
.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow ol{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;}
.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li{position:relative;display:block;padding:150px 20px 22px;border:1px solid #4b626c;min-width:0;background:#17232a;}
.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li:before{content:"";position:absolute;left:20px;right:20px;top:26px;height:98px;background:linear-gradient(#365766 0 4%,#183d50 4% 72%,#95856d 72% 76%,#53483a 76%);border-radius:3px;}
.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li:after{content:"";position:absolute;left:50%;top:34px;height:63px;border-left:2px solid #ffe0b5;}
.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li:nth-child(2):before{background:linear-gradient(#95856d 0 8%,#73644f 8% 42%,#4d4234 42%);}
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.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li>span{color:#f6ce98;}
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@media(max-width:700px){.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow ol{grid-template-columns:1fr;}.atlas-edition:has([data-article=submarine-cables]) #burial .evidence-flow li{padding-top:148px;}}
/* Concrete galleries: charcoal, mineral paper and brass, scoped to the new field. */
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.dam-outlet span{right:0;bottom:22px;}
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@media(max-width:700px){
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 .dam-section-picture span{font-size:14px;padding:4px 6px;}
 .dam-gallery{left:39%;width:17%;border-width:3px;}
 .dam-gallery span{left:-9px;}
 .dam-concrete span{left:18%;}
 .dam-outlet{left:53%;right:3%;top:66%;}
 .dam-outlet span{bottom:-34px;right:0;}
 .dam-reservoir span{left:3%;}
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@media(max-width:700px){.atlas-edition.theme-structures #gallery .science-image>img.source-size-image{margin:0 auto;}}