/* EESP Interactive Science Atlas: navigation and first-visit UX v3.0
   Additive shell; no computational model or lesson logic is changed. */
:root{--atlas-nav-border:rgba(127,227,244,.18);--atlas-nav-mint:#8becd0;--atlas-nav-ink:#d8edf7}
.atlas-skip-link{position:fixed;left:12px;top:-90px;z-index:300;padding:11px 16px;border:2px solid #8becd0;border-radius:9px;background:#06141b;color:#fff;font:700 14px/1.4 system-ui,sans-serif;text-decoration:none}
.atlas-skip-link:focus{top:8px}
.atlas-quicknav{position:relative;z-index:66;display:block;isolation:isolate;background:linear-gradient(110deg,rgba(5,16,26,.99),rgba(7,20,31,.98));border-bottom:1px solid var(--atlas-nav-border);font:600 12px/1.3 system-ui,-apple-system,"Segoe UI",sans-serif}
.atlas-quicknav-inner{width:min(1220px,calc(100% - 28px));margin:0 auto;min-height:54px;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:5px 0}
.atlas-quicknav-label{flex:none;font:700 10px/1.3 ui-monospace,Menlo,monospace;letter-spacing:.14em;color:var(--atlas-nav-mint);text-transform:uppercase}
.atlas-quicknav-links{display:flex;align-items:center;gap:6px;flex-wrap:wrap;justify-content:flex-end}
.atlas-quicknav-link{display:flex;align-items:center;justify-content:center;min-height:36px;padding:7px 12px;border:1px solid transparent;border-radius:10px;color:#b9cfdd;text-decoration:none;white-space:nowrap;transition:border-color .16s ease,background .16s ease,color .16s ease}
.atlas-quicknav-link:hover{color:#fff;border-color:rgba(139,236,208,.27);background:rgba(139,236,208,.07)}
.atlas-quicknav-link[aria-current]{color:#eefffb;border-color:rgba(139,236,208,.33);background:rgba(44,142,123,.17);box-shadow:inset 0 1px rgba(255,255,255,.05)}
.atlas-quicknav-link:focus-visible,.atlas-onramp-card:focus-visible,.atlas-continue a:focus-visible,.atlas-map-preview summary:focus-visible,.atlas-search-clear:focus-visible,.atlas-search-feedback button:focus-visible{outline:2px solid #8bf7d4;outline-offset:3px}
body.embed>.atlas-quicknav,body.embed>.atlas-skip-link{display:none!important}
#atlas-main,#labs,#atlas,#atlas-page-content{scroll-margin-top:125px}
.atlas-onramp{margin:22px 0 28px;position:relative}
.atlas-onramp-heading{display:flex;gap:12px;justify-content:space-between;align-items:baseline;flex-wrap:wrap;margin:0 0 11px}
.atlas-onramp-heading h2{font-size:clamp(17px,2.1vw,22px)!important;font-weight:740!important;line-height:1.28!important;letter-spacing:-.02em!important;margin:0!important;color:#f1feff!important}
.atlas-onramp-heading span{color:#acc8d0;font:500 12px/1.5 system-ui,sans-serif}
.atlas-onramp-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}
.atlas-onramp-card{display:block;position:relative;min-height:134px;padding:16px 15px;border:1px solid rgba(126,232,255,.19);border-radius:17px;text-decoration:none!important;color:#e9f9fe!important;background:linear-gradient(155deg,rgba(15,38,52,.83),rgba(6,17,28,.94));box-shadow:inset 0 1px rgba(255,255,255,.045);transition:transform .17s ease,border-color .17s ease,background .17s ease}
.atlas-onramp-card:before{content:"";position:absolute;inset:0 0 auto;height:2px;background:linear-gradient(90deg,#8becd0,rgba(126,232,255,.1));border-radius:17px 17px 0 0;opacity:.65}
.atlas-onramp-card:hover{transform:translateY(-2px);border-color:rgba(139,236,208,.5);background:linear-gradient(155deg,rgba(23,56,66,.92),rgba(6,24,34,.97))}
.atlas-onramp-card .atlas-card-kicker{display:block;color:#96dacc;font:700 10px/1.3 ui-monospace,Menlo,monospace;text-transform:uppercase;letter-spacing:.11em;margin-bottom:10px}
.atlas-onramp-card strong{display:block;font-size:clamp(14px,1.35vw,18px);line-height:1.35;letter-spacing:-.01em;color:#f3fcff}
.atlas-onramp-card small{display:block;font:400 11px/1.48 system-ui,sans-serif;color:#b3ccd3;margin-top:7px}
.atlas-map-preview{margin:14px 2px 2px}
.atlas-map-preview>summary{cursor:pointer;list-style:none;border:1px solid rgba(129,225,244,.22);border-radius:9px;display:inline-flex;align-items:center;gap:8px;min-height:38px;padding:9px 13px;color:#bfeaf2;font-size:12px}
.atlas-map-preview>summary::-webkit-details-marker{display:none}
.atlas-map-preview>summary:after{content:"+";font-size:17px;line-height:1;font-weight:300}
.atlas-map-preview[open]>summary:after{content:"−"}
.atlas-map-preview iframe{width:100%;display:block;height:min(580px,70vh);margin:12px 0 0;border:1px solid rgba(120,239,193,.15);border-radius:15px;background:#061321}
.atlas-map-hint{font:400 12px/1.6 system-ui,sans-serif;color:#b7c9d5;margin:9px 0 3px}
.atlas-search-field{position:relative;display:flex;align-items:center;min-width:0;flex:1}
.atlas-search-field input{width:100%;min-width:0;padding-right:76px}
.atlas-search-clear{position:absolute;right:7px;top:50%;transform:translateY(-50%);padding:5px 9px;border:1px solid rgba(126,232,255,.28);background:#0c2130;color:#d5f6fb;border-radius:8px;font:600 11px system-ui,sans-serif;cursor:pointer}
.atlas-search-clear[hidden]{display:none}
.atlas-search-feedback{font:400 12px/1.5 system-ui,sans-serif;color:#aacecf;padding:7px 0 10px}
.atlas-search-empty{padding:35px 26px;border:1px solid rgba(126,232,255,.2);background:rgba(11,27,37,.78);border-radius:18px}
.atlas-search-empty h2{font-size:19px;margin:0 0 10px;color:#e8faff}
.atlas-search-empty p{color:#b7ccd8;margin:0 0 18px}
.atlas-search-empty button{border:1px solid rgba(126,232,255,.35);background:rgba(126,232,255,.12);color:#d6f9ff;border-radius:10px;min-height:40px;padding:9px 15px;cursor:pointer}
.atlas-howto{width:min(1220px,calc(100% - 34px));margin:22px auto 20px;padding:14px 18px;border-left:3px solid #8ceacb;border-radius:0 13px 13px 0;background:linear-gradient(100deg,rgba(28,80,74,.23),rgba(8,22,35,.68));color:#d7eaf0;font:400 13px/1.6 system-ui,sans-serif}
.atlas-howto-kicker{display:block;color:#a1ecdb;font:700 10px/1.45 ui-monospace,Consolas,monospace;text-transform:uppercase;letter-spacing:.12em;margin:0 0 6px}
.atlas-howto p{margin:0}.atlas-howto a{color:#a6e9f5;text-underline-offset:3px}
.atlas-continue{width:min(1220px,calc(100% - 34px));margin:55px auto 38px;padding:23px;border:1px solid rgba(126,232,255,.18);border-radius:20px;background:linear-gradient(125deg,rgba(8,28,40,.94),rgba(10,17,29,.94));color:#e5f5f9;font:400 13px/1.5 system-ui,sans-serif}
.atlas-continue h2{font-size:clamp(18px,2vw,24px);margin:0 0 8px;color:#f2feff}
.atlas-continue>p{margin:0 0 18px;color:#aaccd5}
.atlas-continue-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}
.atlas-continue a{display:block;text-decoration:none;border:1px solid rgba(126,232,255,.16);border-radius:13px;padding:13px 15px;color:#e4f9ff;background:rgba(255,255,255,.025)}
.atlas-continue a:hover{border-color:rgba(139,236,208,.46);background:rgba(139,236,208,.07)}
.atlas-continue a small{display:block;color:#8dcfba;font:700 10px/1.5 ui-monospace,Menlo,monospace;text-transform:uppercase;letter-spacing:.1em;margin-bottom:3px}
.atlas-continue a strong{display:block;font-weight:650;font-size:14px}
.atlas-continue-related{margin-top:18px;display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.atlas-continue-related>span{color:#aaccd5;margin-right:6px}
.atlas-continue-related>a{padding:9px 12px;font-size:12px}
.atlas-map-guide{width:min(1220px,calc(100% - 34px));margin:12px auto 18px;padding:17px 20px;border:1px solid rgba(126,232,255,.2);border-radius:15px;background:rgba(8,26,38,.84);color:#d9f1f5;font:400 13px/1.6 system-ui,sans-serif}
.atlas-map-guide strong{display:block;color:#dff8f9;font-size:16px;margin-bottom:6px}
.atlas-map-guide p{margin:0 0 8px}
.atlas-map-guide-links{display:flex;gap:10px;flex-wrap:wrap;margin-top:10px}
.atlas-map-guide-links a{color:#aff5df;text-underline-offset:3px}
.atlas-learning-start{max-width:760px;margin:13px 0 16px;padding:10px 13px;border-left:2px solid #8bedcd;border-radius:0 8px 8px 0;background:rgba(15,53,53,.2);color:#c8e5e8;font:400 13px/1.6 system-ui,sans-serif}
.atlas-learning-start strong{color:#e8fcf6}
.atlas-visually-hidden{position:absolute!important;width:1px!important;height:1px!important;margin:-1px!important;padding:0!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}
@media(min-width:1000px){.isa-home .mission.mapmission{padding:16px 20px}.isa-home .mapmission-head{padding-bottom:3px}}
@media(max-width:850px){.atlas-quicknav-inner{gap:10px}.atlas-quicknav-label{display:none}.atlas-quicknav-links{justify-content:center;flex:1}.atlas-onramp-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.atlas-onramp-card{min-height:124px}}
@media(max-width:540px){
 .atlas-quicknav-inner{width:calc(100% - 18px);padding:7px 0}.atlas-quicknav-links{width:100%;display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:5px}
 .atlas-quicknav-link{grid-column:span 2;min-height:35px;padding:7px 4px;font-size:11.5px;border-color:rgba(128,200,215,.09)}
 .atlas-quicknav-link:nth-child(4),.atlas-quicknav-link:nth-child(5){grid-column:span 3}
 .atlas-onramp{margin:15px 0 21px}.atlas-onramp-card{min-height:113px;padding:13px 11px;border-radius:12px}
 .atlas-onramp-card .atlas-card-kicker{font-size:9px;margin-bottom:7px}.atlas-onramp-card strong{font-size:13px;line-height:1.35}.atlas-onramp-card small{font-size:10.5px}
 .atlas-continue{padding:17px;margin-block:34px}.atlas-continue-grid{grid-template-columns:1fr}.atlas-map-guide{padding:13px}.atlas-howto{padding:12px 15px}
 .isa-home .health{display:none}
}
@media(max-width:345px){.atlas-quicknav-link{font-size:10.5px;padding-inline:3px}.atlas-onramp-card{min-height:130px}}
@media(prefers-reduced-motion:reduce){.atlas-quicknav-link,.atlas-onramp-card{transition:none}.atlas-onramp-card:hover{transform:none}}
@media(forced-colors:active){.atlas-quicknav-link[aria-current],.atlas-onramp-card,.atlas-howto,.atlas-map-guide,.atlas-continue{border:1px solid CanvasText}}
@media print{.atlas-quicknav,.atlas-skip-link,.atlas-onramp,.atlas-continue{display:none!important}}
/* Keep the five major destinations within one tap on long experiments.
   Scroll the redundant per-page header away to avoid three stacked sticky rows. */
:root{--atlas-nav-sticky-h:54px}
.atlas-quicknav{position:sticky;top:var(--eesp-network-h,36px);z-index:78}
.atlas-quicknav~header.top,.atlas-quicknav~header.site-header{position:relative!important;top:auto!important}
.isa-section-nav{top:calc(var(--eesp-network-h,36px) + var(--atlas-nav-sticky-h) + 6px)!important}
.isa-home .toolbar{top:calc(var(--eesp-network-h,36px) + var(--atlas-nav-sticky-h) + 6px)!important}
html{scroll-padding-top:calc(var(--eesp-network-h,36px) + var(--atlas-nav-sticky-h) + 12px)}
@media(min-width:701px){.eesp-network-wide{margin-left:4px}.eesp-network-inner{gap:8px}}
@media(max-width:540px){:root{--atlas-nav-sticky-h:88px}#atlas-main,#labs,#atlas,#atlas-page-content{scroll-margin-top:132px}}