/* Shared controls are isolated from each activity's own styles. */
#lks-navigation{all:initial;box-sizing:border-box;position:fixed;z-index:2147483500;left:max(16px,env(safe-area-inset-left));bottom:max(14px,env(safe-area-inset-bottom));display:flex;gap:4px;padding:5px;background:#12243e;border:1px solid #4274bb;border-radius:16px;box-shadow:0 5px 22px #10223b26;color-scheme:light}
#lks-navigation a{all:unset;box-sizing:border-box;min-height:44px;display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 15px;border-radius:11px;color:#fff;cursor:pointer;text-decoration:none;font:600 14px/1.3 system-ui,sans-serif}
#lks-navigation a:hover{background:#20395b}#lks-navigation a:focus-visible{outline:3px solid #99bbea!important;outline-offset:-2px!important}
#lks-navigation svg{all:unset;width:17px;height:17px;stroke:currentColor;fill:none;stroke-width:1.8;flex-shrink:0}
#lks-navigation .lks-home{background:#fff;color:#12243e}#lks-navigation .lks-home:hover{background:#eaf0f8}
body:has(#lks-navigation) .lco-quick-nav,.lks-hub-return{display:none!important}
.lks-portal{--ink:#16273f;--muted:#3a66a4;--line:#d2def0;--canvas:#f2f5fb;--paper:#fff;--blue-950:#16273f;--blue-900:#1c3251;--blue-800:#244067;--blue-700:#274570;--blue-50:#e6edf6;--blue-100:#dce6f3;--blue-600:#274570;margin:0;background:#f2f5fb;color:#16273f;font:15px/1.65 system-ui,-apple-system,"Segoe UI",sans-serif;color-scheme:light}
.lks-portal *{box-sizing:border-box}.lks-portal .site-shell{width:min(1240px,calc(100% - 64px));margin-inline:auto}
.lks-portal .site-header{position:relative;z-index:20;background:#fff;border-bottom:1px solid #d2def0}
.lks-portal .site-header-inner{display:flex;align-items:center;justify-content:space-between;min-height:82px;gap:24px;padding-block:12px}
.lks-portal .site-brand{display:inline-flex;align-items:center;gap:11px;color:#16273f;text-decoration:none;font-size:18px;font-weight:760;white-space:nowrap}
.lks-portal .site-brand-mark{display:grid;place-items:center;width:42px;height:42px;background:#1f3758;color:#fff;border-radius:13px;font-size:12px;letter-spacing:.04em}
.lks-portal .site-nav{display:flex;gap:4px;flex-wrap:wrap}.lks-portal .site-nav a{padding:10px 15px;font-size:13px;font-weight:650;border-radius:24px;text-decoration:none;color:#325990}
.lks-portal .site-nav a:hover,.lks-portal .site-nav a[aria-current="page"]{background:#e6edf6;color:#1b3151}
.lks-portal :is(a,button,input,select):focus-visible{outline:3px solid #2257a2;outline-offset:4px}
.lks-portal :is(h1,h2,h3){color:#16273f;line-height:1.2}
.lks-eyebrow{display:block;margin:0 0 16px;color:#2a4a77;font-size:11px;font-weight:750;letter-spacing:.16em;text-transform:uppercase}
.lks-hero{display:grid;grid-template-columns:1.1fr .9fr;align-items:center;gap:50px;padding:56px 0 40px}
.lks-hero h1{margin:0 0 20px;font-size:clamp(36px,4.7vw,64px);font-weight:650;letter-spacing:-.055em;max-width:680px}
.lks-hero h1 em{color:#31578d;font-style:normal}.lks-hero p{max-width:550px;margin:0 0 26px;font-size:16px;color:#3a66a4}
.lks-actions{display:flex;flex-wrap:wrap;align-items:center;gap:12px}
.lks-portal .lks-button{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:46px;padding:12px 19px;border:1px solid #213a5e;border-radius:12px;background:#213a5e;color:#fff;text-decoration:none;font:650 13px/1.4 system-ui,sans-serif;cursor:pointer}
.lks-portal .lks-button.secondary{color:#213a5e;background:transparent;border-color:#bdcfe8}
.lks-art{display:flex;flex-direction:column;align-items:center;padding:24px;border:1px solid #cddbee;border-radius:28px;overflow:hidden;background:#e1e9f5}
.lks-art svg{width:min(100%,310px);height:auto}.lks-art-caption{width:100%;display:flex;justify-content:space-between;gap:12px;padding-top:10px;font-size:11px;font-weight:650;color:#2d4f7f;letter-spacing:.06em;text-transform:uppercase}
.lks-stats{display:flex;flex-wrap:wrap;gap:26px;margin-top:30px;color:#3a66a4;font-size:12px}.lks-stats strong{color:#16273f;font-size:18px;padding-right:5px}
.lks-section{margin:24px 0 44px}.lks-heading{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:18px}
.lks-heading h2{margin:0;font-size:25px;letter-spacing:-.025em;font-weight:650}.lks-heading p{margin:0;color:#3a66a4;font-size:13px}
.lks-pathways,.lks-resource-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.lks-pathway{display:flex;flex-direction:column;align-items:start;gap:10px;padding:25px;border:1px solid #cbdaee;border-radius:20px;background:#fff;text-decoration:none;transition:transform .15s,border-color .15s}
.lks-pathway:nth-child(2){background:#e3ebf6}.lks-pathway:nth-child(3){background:#dfebfb}
.lks-pathway:hover,.lks-resource-card:hover{border-color:#5f8ac7;transform:translateY(-3px)}
.lks-icon{display:grid;place-items:center;width:43px;height:43px;border-radius:13px;background:#e6edf6;color:#213a5e}.lks-icon svg{width:25px;height:25px;fill:none;stroke:currentColor;stroke-width:1.5}
.lks-pathway :is(h2,h3){margin:8px 0 0;font-size:21px;letter-spacing:-.025em}.lks-pathway p{margin:0 0 14px;color:#3a66a4;font-size:13px}
.lks-card-bottom{margin-top:auto;display:flex;justify-content:space-between;align-items:center;gap:16px;width:100%;font-weight:650;font-size:12px;color:#213a5e}
.lks-library{padding:30px;border:1px solid #d2def0;border-radius:24px;background:#fff;margin-bottom:60px;scroll-margin-top:20px}
.resource-filters{display:grid;grid-template-columns:minmax(0,1fr) 220px;gap:16px;margin:24px 0 16px}
.resource-filters label{display:block;margin-bottom:6px;font-size:12px;font-weight:650}
.resource-filters :is(input,select){width:100%;height:47px;padding:10px 13px;border:1px solid #bdcfe8;border-radius:11px;background:#f5f8fc;color:#16273f;font:14px system-ui,sans-serif}
#resource-count{color:#3a66a4;font-size:12px;margin:0 0 18px}
.lks-resource-card{display:flex;flex-direction:column;min-height:192px;gap:12px;padding:21px;border:1px solid #d2def0;border-radius:17px;background:#fff;text-decoration:none;transition:transform .15s,border-color .15s}
.lks-resource-top{display:flex;justify-content:space-between;gap:10px;align-items:center}
.lks-resource-tag{padding:4px 8px;background:#eaf0f8;border-radius:6px;font-size:10px;font-weight:650;letter-spacing:.035em;text-transform:uppercase;color:#2b4d7c}
.lks-resource-card h3{margin:0;font-size:17px;letter-spacing:-.02em}.lks-resource-card p{margin:0;font-size:12px;color:#3a66a4}
.lks-resource-card .lks-card-bottom{padding-top:12px;border-top:1px solid #e6edf6}
[data-resource][hidden],#resource-empty[hidden]{display:none!important}#resource-empty{padding:30px;background:#f2f5fb;border-radius:14px;color:#3a66a4}
.lks-breadcrumbs{display:flex;align-items:center;gap:10px;padding-top:25px;color:#3a66a4;font-size:12px}.lks-breadcrumbs a{color:#2a4b78;text-decoration:none}
.lks-subject-intro{padding:28px 0 35px;border-bottom:1px solid #d2def0}.lks-subject-intro h1{margin:0 0 14px;font-size:clamp(32px,4vw,49px);letter-spacing:-.045em;font-weight:650}
.lks-subject-intro p{margin:0;color:#3a66a4;max-width:700px}
.lks-subject-layout{display:grid;grid-template-columns:215px minmax(0,1fr);gap:32px;padding-block:32px 60px}
.lks-topic-nav{align-self:start;position:sticky;top:24px;padding:18px 12px;border:1px solid #d2def0;border-radius:18px;background:#fff}
.lks-topic-nav strong{display:block;padding:0 10px 13px;font-size:10px;text-transform:uppercase;letter-spacing:.12em;color:#3a66a4}
.lks-topic-nav a{display:block;padding:11px 10px;border-radius:8px;text-decoration:none;font-size:12px;color:#213a5e}.lks-topic-nav a:hover{background:#e9eff8}
.lks-topic-section{margin-bottom:35px;scroll-margin-top:20px}.lks-topic-section .lks-resource-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
.lks-topic-count{font-size:12px;font-weight:500;color:#3a66a4;white-space:nowrap}
.lks-portal .site-footer{background:#e6edf7;border-top:1px solid #cbdaee;margin:0;padding:0}
.lks-portal .site-footer-inner{display:flex;justify-content:space-between;gap:20px;padding:24px 0 100px;color:#3a66a4;font-size:12px}
.lks-portal .page-band{background:#e3ebf6;color:#16273f;border-bottom:1px solid #cbdaee}.lks-portal .page-band-inner{padding-block:38px}
.lks-portal .page-band h1{color:#16273f;font-size:clamp(32px,4vw,49px);letter-spacing:-.04em}.lks-portal :is(.page-intro,.page-kicker){color:#335a91}
.lks-portal .site-card{border:1px solid #cbdaee;border-radius:18px;box-shadow:none;padding:23px}
.lks-portal .content-section-title{border-bottom:1px solid #cbdaee;padding-bottom:14px;font-size:21px}.lks-portal .page-main{padding-block:30px 60px}
.lks-portal .link-row{border-color:#cbdaee;border-radius:12px}.lks-portal :is(.badge,.row-tag){color:#2b4d7c}.lks-portal .section-heading h2{color:#16273f}
.lks-account-page{background:#f2f5fb!important;color:#16273f!important}.lks-account-page .box{border-radius:24px;border-color:#cbdaee;box-shadow:0 15px 55px #12243e0b}.lks-account-page .box h1{color:#16273f}
@media(min-width:1700px){.lks-portal .site-shell{width:min(1380px,calc(100% - 96px))}}
@media(max-width:950px){.lks-hero{gap:25px}.lks-subject-layout{grid-template-columns:170px minmax(0,1fr);gap:22px}.lks-resource-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:720px){
 .lks-portal .site-shell{width:calc(100% - 32px)}.lks-portal .site-header-inner{flex-direction:column;align-items:flex-start;gap:12px;padding-block:15px 12px}
 .lks-portal .site-nav{width:100%;display:flex;flex-wrap:nowrap;gap:3px;overflow-x:auto}.lks-portal .site-nav a{white-space:nowrap;padding:9px 11px;font-size:11px;flex-shrink:0}
 .lks-hero{grid-template-columns:1fr;padding-top:32px;gap:28px}.lks-hero h1{font-size:43px}.lks-art{display:none}
 .lks-pathways{grid-template-columns:1fr;gap:12px}.lks-pathway{padding:21px}.lks-heading{align-items:start;flex-direction:column;gap:6px}.lks-heading h2{font-size:23px}
 .lks-library{padding:20px 16px}.resource-filters{grid-template-columns:1fr;gap:10px}.lks-subject-layout{display:block}
 .lks-topic-nav{position:static;display:flex;overflow-x:auto;align-items:center;gap:5px;padding:8px;margin-bottom:26px}.lks-topic-nav strong{display:none}.lks-topic-nav a{white-space:nowrap}
 .lks-topic-section .lks-resource-grid,.lks-resource-grid{grid-template-columns:1fr}.lks-resource-card{min-height:160px}.lks-portal .site-footer-inner{flex-direction:column;gap:5px}
}
@media(prefers-reduced-motion:reduce){.lks-portal *{scroll-behavior:auto!important;transition:none!important}}
/* The assessment suite has older !important shape rules. Override them locally. */
#lks-navigation{border-radius:16px!important;max-width:calc(100vw - 28px)!important}
#lks-navigation a{border-radius:11px!important}
body.lks-toolkit-page{--exam-ink:#16273f;--exam-muted:#3a66a4;--exam-primary:#213a5e;--exam-primary-dark:#16273f;--exam-primary-soft:#e9eff8;--exam-canvas:#f2f5fb;--exam-line:#cbdaee;--exam-radius:16px;background:#f2f5fb!important;background-image:none!important}
.lks-toolkit-page :is(.box,.panel,.card,.exam){border-radius:16px!important;border-color:#cbdaee!important}
.lks-toolkit-page :is(input,select,textarea,button,.btn){border-radius:9px!important}
body.lks-account-page{box-sizing:border-box!important;width:100%!important;min-width:0!important;min-height:100dvh;grid-template-columns:minmax(0,1fr);padding:28px 0 96px!important}
.lks-account-page #loginForm.box,.lks-account-page #passwordForm.box{box-sizing:border-box!important;width:min(480px,calc(100vw - 32px))!important;max-width:100%!important;margin:0 auto!important;padding:28px!important;border-radius:24px!important;box-shadow:0 15px 55px #12243e0b!important}
.lks-account-page .box :is(input,button){box-sizing:border-box!important;width:100%!important;border-radius:10px!important}
.lks-account-page .box .btn-primary{background:#213a5e!important;border-color:#213a5e!important;color:#fff!important;box-shadow:none!important}
.lks-account-page .box h1{font-size:25px!important;line-height:1.25!important}
.lks-account-page #loginForm h1::after{border-radius:6px!important;background:#e9eff8!important;color:#335a91!important}
@media print{#lks-navigation,.lks-portal .site-header{display:none!important}}
/* A shared workspace layout for both public and authenticated toolkit pages. */
body.lks-toolkit-page{--exam-primary:#2563eb;--exam-primary-dark:#1e40af;--exam-primary-soft:#eff6ff;--exam-ink:#172b4d;--exam-muted:#60728c;--exam-line:#dbe5f3;--exam-canvas:#f3f7fd;--exam-radius:18px;color:#172b4d;font:15px/1.55 system-ui,-apple-system,"Segoe UI",sans-serif;padding-bottom:96px!important}
.lks-toolkit-page :is(main.shell,main.wrap,body>.container){width:min(1280px,calc(100% - 48px));margin-inline:auto}
.lks-toolkit-page .page-head{padding:32px 0!important;border-bottom:1px solid #dbe5f3;margin-bottom:26px}
.lks-toolkit-page h1{font-size:clamp(28px,3vw,40px)!important;line-height:1.2;letter-spacing:-.035em!important;color:#172b4d!important}
.lks-toolkit-page :is(.card,.panel,.exam,.box){border:1px solid #dbe5f3!important;border-radius:18px!important;background:#fff!important;box-shadow:0 8px 28px #163c7110!important}
.lks-toolkit-page :is(.panel-head,.head,.exam-title-row){padding:20px 24px;border-bottom-color:#e2eaf5!important;background:#f8fbff!important;border-radius:18px 18px 0 0!important}
.lks-toolkit-page :is(.stage,.toolbar,.metric,.stat,.empty,.search){border-radius:12px!important}
.lks-toolkit-page .stage{padding:20px!important;background:#f8fbff!important;border:1px solid #e2eaf5!important}
.lks-toolkit-page :is(.btn,button,input,select,textarea){border-radius:10px!important}
.lks-toolkit-page :is(.btn-primary,.btn.primary,button.primary,.tab-btn.active){background:#2563eb!important;border-color:#2563eb!important;color:#fff!important}
.lks-toolkit-page :is(.btn-secondary,.btn-outline){background:#eff6ff!important;border-color:#cbdcf6!important;color:#1d4ed8!important}
.lks-toolkit-page :is(.topbar,.exam-toolbar){background:#fff!important;border-bottom:1px solid #dbe5f3!important;box-shadow:0 4px 22px #163c7108!important}
.lks-toolkit-page .topbar{padding-block:18px;gap:16px}
.lks-toolkit-page .brand-mark,.lks-toolkit-page .exam-toolbar-brand::before{border-radius:12px!important;background:#2563eb!important;color:#fff!important}
.lks-toolkit-page .exam-toolbar-links{border:0!important;background:#eff6ff!important;border-radius:12px!important;max-width:100%;overflow-x:auto}
.lks-toolkit-page .exam-toolbar :is(a,button){border-radius:9px!important;flex-shrink:0}
.lks-toolkit-page .exam-toolbar a[aria-current=page]{background:#2563eb!important;color:#fff!important;border-color:#2563eb!important}
.lks-toolkit-page .exam-toolbar-scope{border-radius:7px!important}
.lks-toolkit-page .results-panel{padding:24px!important;border-top:4px solid #2563eb!important}
.lks-toolkit-page .result-main{border-radius:14px!important;background:#eff6ff!important;color:#1d4ed8!important}
.lks-toolkit-page .setup-grid{padding:22px!important;background:#f8fbff;border-radius:18px 18px 0 0!important;gap:16px!important}
.lks-toolkit-page .table-head,.lks-toolkit-page th{background:#eff6ff!important;color:#284b7a!important}
.lks-toolkit-page .workspace{gap:24px!important}
.lks-toolkit-page :is(.top-actions,.actions,.row-actions){gap:10px}
.lks-toolkit-page .brand{color:#172b4d!important}
@media(max-width:1000px){.lks-toolkit-page .exam-toolbar{flex-wrap:wrap;gap:8px;padding:12px 20px}.lks-toolkit-page .exam-toolbar-links{flex:1 0 100%;justify-content:flex-start}.lks-toolkit-page.has-exam-toolbar{padding-top:144px!important}}
@media(max-width:680px){.lks-toolkit-page :is(main.shell,main.wrap,body>.container){width:calc(100% - 28px)}.lks-toolkit-page .page-head{padding:22px 0!important}.lks-toolkit-page :is(.panel-head,.head,.exam-title-row){padding:16px}.lks-toolkit-page .topbar{flex-wrap:wrap}.lks-toolkit-page .top-actions{flex-wrap:wrap}.lks-toolkit-page .setup-grid{padding:16px!important}}

.lks-portal .lks-button,.lks-portal .site-brand-mark{background:#2563eb;border-color:#2563eb}.lks-portal .lks-button.secondary{background:#eff6ff;color:#1d4ed8;border-color:#cbdcf6}.lks-hero h1 em{color:#2563eb}#lks-navigation{background:#1e40af;border-color:#5079c4}#lks-navigation .lks-home{color:#1e40af}.lks-account-page .box .btn-primary{background:#2563eb!important;border-color:#2563eb!important}
/* Reserve a footer lane in fullscreen lessons so navigation cannot cover controls. */
.lks-portal{--unit-purple:#2563eb;--unit-purple-dark:#173b78;--unit-purple-soft:#eff6ff}
.lks-portal .activity-head :is(h1,h2,h3){color:#fff}
.lks-portal .activity-shell .panel{border-radius:18px;border-color:#dce5f2;box-shadow:0 8px 24px #1c407b08}
.lks-portal .activity-head{border-radius:18px}
body[data-lco-activity]{--primary:#60a5fa;--primary-variant:#1d4ed8;--secondary:#93c5fd}
body[data-lco-activity]>:is(#app-container,#game-container,#app,.app-container,#appShell,#appRoot,#game-shell,#app-wrapper){background-color:#08172e!important;background-image:none!important}
html:has(#lks-navigation){scroll-padding-bottom:96px}
body:has(#lks-navigation) :is(input,select,button,a){scroll-margin-bottom:96px}
body[data-lco-activity]{--lco-panel:#10274d;--lco-accent:#60a5fa;--lco-line:#6a9ee34d;--lco-focus:#93c5fd;--panel-bg:#10274d;--bg-color:#08172e;--bg-dark:#08172e;--accent:#60a5fa;--accent-color:#60a5fa;--accent-hover:#93c5fd;--lks-activity-height:calc(100dvh - 76px);padding-bottom:76px!important;box-sizing:border-box;background-color:#08172e!important;background-image:none!important}
body[data-lco-activity]>:is(#app-container,#game-container,#app,.app-container,#appShell,#appRoot,#game-shell,#app-wrapper,.host,.shell),body[data-lco-activity]>.host>#appShell,body[data-lco-activity]>.shell>#appRoot{height:var(--lks-activity-height)!important;min-height:var(--lks-activity-height)!important;max-height:var(--lks-activity-height)!important}
body[data-lco-activity="rusting-lab"] .lab-container{min-width:0;grid-template-columns:repeat(2,minmax(0,1fr))}
body[data-lco-activity="rusting-lab"] .card{min-width:0}
body[data-lco-activity="ions-equation-solubility-and-observations"]>#app-container{height:auto!important;min-height:0!important;max-height:none!important}
body[data-lco-activity] :is(#pdf-render-zone,#vocab-pdf-render-zone,#temp-pdf-container) :is(h1,h2,h3,h4,h5,h6,label){color:#000!important}
@media(max-width:850px){body[data-lco-activity="rusting-lab"] .lab-container{grid-template-columns:minmax(0,1fr)}}
@media(max-width:480px){body[data-lco-activity="rusting-lab"]{padding-inline:12px!important}body[data-lco-activity="rusting-lab"] .setup-area{gap:8px;padding:10px;flex-wrap:wrap}}
@media print{body[data-lco-activity]{padding-bottom:0!important;background:#fff!important}body[data-lco-activity] :is(h1,h2,h3,h4,label){color:inherit!important}}