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:root[data-theme=scope]{--blue:#61dbab;--blue-dark:#91efc9;--ink:#e2f5ec;--muted:#adcbc1;--line:#315449;--page:#0b221d;--soft:#173e32;--surface:#122e26;--green:#93e6b6;--green-soft:#194833;--orange-soft:#423720;--gold:#e0c578}
:root[data-theme=night]{--blue:#95a9ff;--blue-dark:#c1ceff;--ink:#e8edff;--muted:#b0bfd9;--line:#344460;--page:#10172a;--soft:#253255;--surface:#1b263e;--green:#91dfb4;--green-soft:#193d37;--orange-soft:#463c28;--gold:#edc46f}
:root[data-theme=scope] :is(.sidebar,.topbar,.foundation-card,.concept-card,.experiment-prompt,.prediction,.circuit-card,.secondary,.reference,.lesson-text,.quiz-card,.answer-option,.completion,.nav-number,.switch,.skip-link),:root[data-theme=night] :is(.sidebar,.topbar,.foundation-card,.concept-card,.experiment-prompt,.prediction,.circuit-card,.secondary,.reference,.lesson-text,.quiz-card,.answer-option,.completion,.nav-number,.switch,.skip-link){background:var(--surface)}
:root[data-theme=scope] :is(.reference.blue,.prediction.selected,.answer-option.selected,.secondary.selected,.nav-lesson.active),:root[data-theme=night] :is(.reference.blue,.prediction.selected,.answer-option.selected,.secondary.selected,.nav-lesson.active){background:var(--soft);border-color:var(--blue)}
:root[data-theme=scope] .diagram-wrap,:root[data-theme=night] .diagram-wrap{background-color:var(--page);background-image:radial-gradient(var(--line) .75px,transparent .75px)}
:root[data-theme=scope] :is(.diagram .component,.circuit-svg .component),:root[data-theme=night] :is(.diagram .component,.circuit-svg .component){fill:var(--soft);stroke:var(--blue)}
:root[data-theme=scope] .diagram :is(.small-svg,.current-label),:root[data-theme=night] .diagram :is(.small-svg,.current-label){fill:var(--muted)}
:root[data-theme=scope] :is(.numeric-answer input,.takeaway),:root[data-theme=night] :is(.numeric-answer input,.takeaway){background:var(--page);color:var(--ink)}
:root[data-theme=scope] :is(.primary:not(:disabled),.active .step-num,.active .nav-number),:root[data-theme=night] :is(.primary:not(:disabled),.active .step-num,.active .nav-number){color:var(--page);border-bottom-color:var(--blue)}
:root[data-theme=scope] :is(.observation,.feedback.correct),:root[data-theme=night] :is(.observation,.feedback.correct){color:var(--green)}
:root[data-theme=scope] :is(.hint-content,.feedback.wrong),:root[data-theme=night] :is(.hint-content,.feedback.wrong){color:var(--gold)}
@media(min-width:1550px){.reward-grid{grid-template-columns:repeat(4,minmax(0,1fr))}.theme-preview{flex-direction:column;height:160px;padding:15px}.theme-preview svg{width:80%}}
@media(max-width:1000px){.review-grid{grid-template-columns:1fr}.topbar-label{font-size:10px;letter-spacing:.6px}}
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/* Keep the question, circuit, and formula card together when opening an experiment. */
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.experiment-mode .content{padding-top:16px}
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.experiment-mode .prediction-options{gap:8px}
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.experiment-mode .circuit-toolbar{padding:8px 16px;min-height:40px}
.experiment-mode .diagram{min-height:180px;max-height:260px}
.experiment-mode .diagram-wrap{padding:4px 8px 0}
.experiment-mode .readings{padding:10px 0}
.experiment-mode .controls{padding:14px 16px;gap:14px}
.experiment-mode .lab-ranges{grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:14px 20px}
.experiment-mode .sim-note{padding-top:10px}
@media(max-width:1000px){.experiment-mode .aside{grid-template-columns:1fr 1fr}}
@media(max-width:720px){
  .experiment-mode .content{padding:12px 14px 20px}
  .experiment-mode .experiment-intro{align-items:flex-start;gap:10px}
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  .experiment-mode .prediction{font-size:14px;padding:7px 10px}
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  .experiment-mode .circuit-title{font-size:13px}
  .experiment-mode .diagram{min-height:170px;max-height:210px}
  .experiment-mode .diagram-wrap{padding:4px 0 0}
  .experiment-mode .aside{grid-template-columns:minmax(0,1fr)}
}
/* Home: a clear starting point and a compact overview of earned progress. */
.home-mode .topbar{height:56px}
.home-mode .content{padding-top:24px}
.home-mode .sidebar :is(.unit-label,.unit-picker,.lesson-nav){display:none}
.home-welcome{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(250px,1fr);gap:28px;padding:24px;background:var(--surface,#fff);border:1px solid var(--line);border-radius:16px;margin-bottom:20px}
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.home-start>span{font-size:14px;line-height:1.5;color:var(--muted);max-width:245px}
.home-guide,.home-goal{border-left:1px solid var(--line);padding-left:24px;align-self:center}
.home-guide h2{font-size:17px;margin:0 0 14px}
.home-guide ol{list-style:none;padding:0;margin:0;display:grid;gap:13px}
.home-guide li{display:flex;align-items:flex-start;gap:11px}
.home-guide li>span{display:grid;place-items:center;width:28px;height:28px;flex:none;border-radius:50%;background:var(--soft);color:var(--blue);font-size:14px;font-weight:750}
.home-guide strong{display:block;font-size:15px;line-height:1.4}
.home-guide p{font-size:14px;line-height:1.5;color:var(--muted);margin:3px 0 0}
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.home-goal h2{font-size:21px;margin:0 0 7px}
.home-goal p{font-size:14px;line-height:1.6;color:var(--muted);margin:0 0 5px}
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.home-stats>div{display:grid;gap:3px;text-align:center;border-right:1px solid var(--line);min-width:0;padding:0 10px}
.home-stats>div:last-child{border:0}
.home-stats .home-stat-value{font-size:30px;line-height:1.2;font-weight:750;color:var(--blue);font-variant-numeric:tabular-nums;letter-spacing:-.6px}
.home-stat-value small{font-size:17px;color:var(--muted);font-weight:500;letter-spacing:0}
.home-stats>div>span:last-child{font-size:14px;line-height:1.4;color:var(--muted)}
.home-topics-heading{display:flex;align-items:baseline;justify-content:space-between;gap:12px;flex-wrap:wrap;margin:0 0 14px}
.home-topics-heading h2{font-size:20px;margin:0}
.home-topics-heading>span{font-size:14px;color:var(--muted)}
.home-units{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.home-unit{padding:17px 18px 12px;border:1px solid var(--line);border-radius:14px;background:var(--surface,#fff);min-width:0}
.home-unit-heading{display:flex;align-items:center;gap:10px;margin-bottom:10px}
.home-unit-number{display:grid;place-items:center;flex:none;width:30px;height:30px;border-radius:9px;background:var(--soft);font-size:14px;font-weight:700;color:var(--blue)}
.home-unit h3{font-size:17px;line-height:1.3;margin:0;min-width:0}
.home-unit-count{margin-left:auto;font-size:14px;color:var(--muted);font-variant-numeric:tabular-nums;white-space:nowrap}
.home-unit>p{font-size:14px;line-height:1.5;color:var(--muted);min-height:42px;margin:0 0 12px}
.home-unit-track{height:6px;overflow:hidden;background:var(--line);border-radius:8px}
.home-unit-track>span{height:100%;display:block;background:var(--blue);border-radius:8px}
.home-unit-footer{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:5px}
.home-unit-footer>span{font-size:14px;color:var(--muted);white-space:nowrap}
.home-unit-footer .text-button{font-size:14px;font-weight:650;color:var(--blue-dark);padding:8px 0;min-height:36px}
.home-unit-complete .home-unit-number{background:var(--green-soft);color:var(--green)}
.home-unit-complete .home-unit-track>span{background:var(--green)}
@media(max-width:1100px){.home-units{grid-template-columns:repeat(2,minmax(0,1fr))}.home-welcome{grid-template-columns:minmax(0,1fr);gap:20px}.home-guide{border-left:0;border-top:1px solid var(--line);padding:18px 0 0}.home-guide ol{grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.home-guide li{flex-direction:column;gap:7px}.home-goal{padding:16px 18px}}
@media(max-width:720px){.section-links{flex-wrap:wrap}.section-links button{padding-inline:8px}.home-mode .content{padding:20px 14px}.home-welcome{padding:20px;gap:18px}.home-welcome h1{font-size:27px}.home-start{align-items:flex-start;flex-direction:column;gap:10px}.home-start>span{max-width:none}.home-guide h2{font-size:16px}.home-guide ol{grid-template-columns:1fr;gap:12px}.home-guide li{flex-direction:row;gap:10px}.home-guide strong{font-size:15px}.home-stats{padding:15px 0;margin-bottom:22px}.home-stats>div{padding:0 7px}.home-stats .home-stat-value{font-size:26px}.home-stat-value small{font-size:15px}.home-stats>div>span:last-child{font-size:14px;overflow-wrap:break-word}.home-topics-heading{gap:5px}.home-topics-heading h2{font-size:20px}.home-units{grid-template-columns:1fr;gap:12px}.home-unit>p{min-height:0}.home-unit{padding:17px 18px 12px}}
@media(max-width:720px){.home-mode .home-goal{display:none}}
.pet-card{border:1px solid var(--line);border-radius:16px;background:var(--surface,#fff);padding:22px 24px;margin:0 0 22px;overflow:hidden}
.pet-heading{display:flex;align-items:center;justify-content:space-between;gap:14px}
.pet-heading .small-label{font-size:11px;margin:0 0 2px}
.pet-heading h2{font-size:24px;margin:0}
.pet-level{font-size:12px;font-weight:650;color:var(--blue-dark);background:var(--soft);border:1px solid var(--line);border-radius:20px;padding:6px 11px;white-space:nowrap}
.pet-layout{display:grid;grid-template-columns:minmax(230px,310px) minmax(0,1fr);align-items:center;gap:24px}
.pet-home{min-width:0;text-align:center}
.pet-stage{width:100%;max-width:300px;aspect-ratio:1;position:relative;margin:-12px auto 0;isolation:isolate}
.pet-figure,.pet-egg-shell{position:absolute;inset:0;background-image:url('assets/jere-evolution.png');background-repeat:no-repeat;background-size:300% 200%;background-position:var(--pet-position);transform:scale(var(--pet-scale));transform-origin:50% 90%;z-index:1;pointer-events:none}
.pet-figure{clip-path:inset(0 0 7% 0)}
.pet-floor{position:absolute;left:25%;right:25%;top:88%;height:5%;background:radial-gradient(ellipse,var(--line),transparent 70%);z-index:0}
.pet-mood{font-size:13px;color:var(--muted);margin:0 0 6px;min-height:21px}
.pet-total{display:block;font-size:12px;font-weight:650;color:var(--blue-dark);margin-top:3px}
.pet-hatch-notice{display:grid;justify-items:center;gap:2px;padding:12px 16px;background:var(--soft);border:1px solid var(--line);border-radius:10px;margin:0 auto 22px;max-width:410px;font-size:14px;color:var(--blue-dark)}
.pet-hatch-notice .text-button{color:var(--blue-dark);font-weight:650}
.pet-care{padding:15px 0 6px;min-width:0}
.pet-care h3{font-size:20px;line-height:1.4;margin:0 0 10px;max-width:350px}
.pet-care>p{font-size:14px;color:var(--muted);line-height:1.65}
.pet-care .primary{white-space:normal;margin-top:4px}
.pet-xp-heading{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin-bottom:10px}
.pet-xp-heading strong{font-size:14px;line-height:1.4}
.pet-xp-heading>span{font-size:14px;font-weight:750;color:var(--blue-dark);white-space:nowrap}
.pet-xp-track{height:9px;overflow:hidden;background:var(--line);border-radius:10px}
.pet-xp-track>span{display:block;height:100%;background:var(--blue);border-radius:10px;transition:width .35s}
.pet-care .pet-help{margin:10px 0 18px;font-size:13px;line-height:1.55}
.pet-stages{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:5px;margin:0 0 20px}
.pet-stages>span{display:grid;justify-items:center;gap:5px;color:var(--muted);position:relative;text-align:center}
.pet-stages>span:not(:last-child):after{content:'';height:2px;background:var(--line);position:absolute;left:calc(50% + 17px);right:calc(-50% + 17px);top:14px}
.pet-stages b{border:1px solid var(--line);width:29px;height:29px;display:grid;place-items:center;border-radius:50%;font-size:12px;font-weight:650;background:var(--page);z-index:1}
.pet-stages small{font-size:10px;line-height:1.3}
.pet-stages .done b{background:var(--green-soft);border-color:var(--green);color:var(--green)}
.pet-stages .current b{background:var(--blue);border-color:var(--blue);color:var(--surface,#fff);box-shadow:0 0 0 3px var(--soft)}
.pet-stages .current small{color:var(--blue-dark);font-weight:750}
.pet-menu-toggle{width:100%;display:flex;align-items:center;gap:9px;text-align:left;min-height:48px;padding:8px 12px}
.pet-menu-toggle svg{width:28px;height:28px;flex:none}
.pet-menu-toggle>span:last-child{margin-left:auto;font-size:20px;font-weight:400;color:var(--muted)}
.pet-menu-toggle b{display:inline-grid;place-items:center;background:var(--soft);color:var(--blue-dark);min-width:24px;height:24px;border-radius:7px;font-size:12px;margin-left:5px}
.pet-badge-menu{border:1px solid var(--line);border-radius:10px;margin-top:9px;padding:12px;background:var(--page)}
.pet-badge-menu[hidden]{display:none}
.pet-menu-instruction{font-size:12px;color:var(--muted);margin:0 0 10px;line-height:1.5}
.pet-badges{max-height:192px;overflow-y:auto;display:grid;gap:8px;padding:3px;scrollbar-width:thin;overscroll-behavior:contain}
.pet-badge{display:flex;align-items:center;gap:9px;text-align:left;background:var(--surface,#fff);border:1px solid var(--line);border-radius:8px;padding:8px 10px;font-size:13px;line-height:1.4;cursor:grab;touch-action:pan-y;user-select:none;min-height:48px}
.pet-badge:active{cursor:grabbing}
.pet-badge>.pet-badge-handle{flex:none;width:32px;height:32px;display:block;touch-action:none;pointer-events:auto;cursor:grab}
.pet-badge svg{width:32px;height:32px;flex:none;pointer-events:none}
.pet-badge>span{flex:1;pointer-events:none}
.pet-badge small{font-size:11px;color:var(--muted);white-space:nowrap;pointer-events:none}
.pet-badge:hover,.pet-badge.selected{border-color:var(--blue);background:var(--soft)}
.pet-badge.selected{box-shadow:inset 0 0 0 1px var(--blue)}
.pet-badge-note{font-size:11px;color:var(--muted);margin:11px 0 0;line-height:1.5}
.pet-empty{font-size:13px;padding:3px}
.pet-empty strong{display:block;margin-bottom:4px}
.pet-empty p{font-size:12px;color:var(--muted);margin:0}
.pet-empty .text-button{color:var(--blue-dark);padding-bottom:2px}
.pet-selection{font-size:12px!important;line-height:1.5!important;margin:9px 0 0;min-height:18px}
.pet-status{font-size:13px!important;font-weight:650;color:var(--blue-dark)!important;margin:8px 0 0!important}
.pet-status:empty{display:none}
.pet-mouth{position:absolute;left:var(--mouth-x);top:var(--mouth-y);transform:translate(-50%,-50%);width:54px;height:48px;border-radius:45%;border:2px dashed transparent;background:transparent;z-index:3;display:grid;place-items:center;transition:background .15s,border-color .15s;cursor:pointer}
.pet-mouth>span{opacity:0;position:absolute;right:-10px;top:-13px;width:21px;height:21px;display:grid;place-items:center;border-radius:50%;background:var(--soft);color:var(--blue-dark);font-size:16px;line-height:1;font-weight:750}
.pet-ready .pet-mouth,.pet-dragging .pet-mouth,.pet-mouth:focus-visible{border-color:var(--blue);background:color-mix(in srgb,var(--soft) 12%,transparent);box-shadow:0 0 0 5px color-mix(in srgb,var(--soft) 35%,transparent)}
.pet-ready .pet-mouth>span,.pet-dragging .pet-mouth>span,.pet-mouth:focus-visible>span{opacity:1}
.pet-over-mouth .pet-mouth{border-style:solid;border-color:var(--green);background:color-mix(in srgb,var(--green-soft) 12%,transparent);box-shadow:0 0 0 8px color-mix(in srgb,var(--green-soft) 70%,transparent)}
.pet-drag-ghost{position:fixed;width:52px;height:52px;transform:translate(-50%,-60%);z-index:1000;pointer-events:none;filter:drop-shadow(0 4px 5px #0003)}
.pet-drag-ghost svg{width:100%;height:100%}
.pet-xp-pop{position:absolute;left:50%;top:30%;transform:translateX(-50%);z-index:4;color:var(--blue-dark);background:var(--soft);padding:5px 11px;border-radius:15px;font-size:14px;font-weight:750;pointer-events:none;animation:jere-xp 1.4s both}
.pet-fed .pet-figure{animation:jere-bounce .65s ease}
.pet-evolved .pet-figure{animation:jere-evolve 1.2s ease}
.pet-egg-shell{--pet-position:0% 0%;--pet-scale:.78;z-index:5}
.pet-shell-left{clip-path:polygon(0 0,52% 0,47% 43%,53% 54%,48% 66%,53% 78%,50% 100%,0 100%);animation:jere-shell-left 1.1s .2s ease-in forwards}
.pet-shell-right{clip-path:polygon(52% 0,100% 0,100% 100%,50% 100%,53% 78%,48% 66%,53% 54%,47% 43%);animation:jere-shell-right 1.1s .2s ease-in forwards}
.is-hatching .pet-figure{animation:jere-hatch 1.4s both}
@keyframes jere-bounce{0%,100%{transform:scale(var(--pet-scale))}35%{transform:translateY(-14px) scale(calc(var(--pet-scale)*1.06))}65%{transform:scale(calc(var(--pet-scale)*.96),calc(var(--pet-scale)*1.04))}}
@keyframes jere-evolve{0%{opacity:.3;transform:scale(calc(var(--pet-scale)*.7));filter:brightness(2)}60%{opacity:1;transform:scale(calc(var(--pet-scale)*1.08));filter:brightness(1.3)}100%{transform:scale(var(--pet-scale));filter:brightness(1)}}
@keyframes jere-xp{0%{opacity:0;translate:0 8px}15%,70%{opacity:1}100%{opacity:0;translate:0 -28px}}
@keyframes jere-shell-left{0%{opacity:1;transform:scale(.78)}100%{opacity:0;transform:translate(-65px,35px) rotate(-28deg) scale(.6)}}
@keyframes jere-shell-right{0%{opacity:1;transform:scale(.78)}100%{opacity:0;transform:translate(65px,35px) rotate(28deg) scale(.6)}}
@keyframes jere-hatch{0%,25%{opacity:0;transform:scale(.15)}75%{opacity:1;transform:scale(calc(var(--pet-scale)*1.15))}100%{opacity:1;transform:scale(var(--pet-scale))}}
@media(max-width:1000px){.pet-card{padding:20px}.pet-layout{grid-template-columns:minmax(190px,240px) minmax(0,1fr);gap:18px}.pet-stage{max-width:250px}.pet-heading h2{font-size:23px}.pet-xp-heading{flex-wrap:wrap;gap:3px}.pet-stages small{font-size:9px}}
@media(max-width:820px){.pet-layout{grid-template-columns:minmax(0,1fr)}.pet-stage{max-width:255px;margin-top:-20px}.pet-mood{margin-top:-4px}.pet-care{padding-top:6px}.pet-xp-heading{flex-wrap:nowrap}.pet-stages small{font-size:11px}}
@media(max-width:720px){.pet-card{padding:18px;margin-bottom:20px}.pet-heading{gap:7px;align-items:flex-start}.pet-level{font-size:11px;padding:5px 8px}.pet-layout{gap:8px}.pet-stage{max-width:235px;margin-top:-24px}.pet-care h3{font-size:18px}.pet-care .primary{width:100%}.pet-xp-heading{font-size:13px;gap:8px;flex-wrap:wrap}.pet-xp-heading strong{font-size:13px}.pet-stages{margin-bottom:15px}.pet-stages small{font-size:10px}.pet-card .pet-mouth:focus-visible{outline-offset:6px}}
@media(prefers-reduced-motion:reduce){.pet-figure,.pet-xp-pop{animation:none!important}.pet-egg-shell{display:none}.pet-xp-track>span{transition:none}.pet-xp-pop{display:none}}
/* Comprehensive Learning Platform additions */
.due-banner{border:1px solid var(--line);border-left:4px solid var(--blue);border-radius:14px;background:var(--surface,#fff);padding:18px 20px;margin:0 0 22px;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.due-banner h2{font-size:19px;margin:0 0 4px}
.due-banner p{font-size:14px;color:var(--muted);margin:0}
.due-actions{display:flex;gap:8px;flex-wrap:wrap}
.probe-panel{border-top:1px solid var(--line);padding:14px 20px;background:var(--soft)}
.probe-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:10px;margin-top:6px}
.probe-item{background:var(--surface,#fff);border:1px solid var(--line);border-radius:8px;padding:8px 12px;display:flex;flex-direction:column;gap:2px}
.probe-item span{font-size:12px;color:var(--muted)}
.probe-item strong{font-size:15px;color:var(--blue-dark);font-variant-numeric:tabular-nums}
.fading-example{margin-top:18px;padding:18px;border:1px solid var(--line);border-radius:10px;background:var(--surface,#fff)}
.fading-example h3{font-size:16px;margin:2px 0 8px}
.fading-row{font-size:15px;margin-bottom:10px;color:var(--ink)}
.fading-controls{display:flex;align-items:center;gap:10px;flex-wrap:wrap}
.fading-controls input{width:130px;border:1px solid var(--line);border-radius:8px;padding:8px 12px;font-size:16px;font-weight:650;background:var(--page);color:var(--ink)}
.fading-feedback{margin:10px 0 0;padding:10px 12px;border-radius:8px;font-size:14px}
.fading-feedback.correct{background:var(--green-soft);color:var(--green)}
.fading-feedback.wrong{background:var(--orange-soft);color:var(--orange,#9f5209)}
.prereq-box p{font-size:13px;margin-bottom:8px}
.prereq-links{display:flex;flex-wrap:wrap;gap:6px}
.prereq-links .secondary{font-size:12px;padding:5px 10px}
.notes-box p{font-size:13px;margin-bottom:8px}
.note-textarea{width:100%;font:inherit;font-size:13px;line-height:1.5;padding:9px 11px;border:1px solid var(--line);border-radius:8px;background:var(--page);color:var(--ink);resize:vertical}
.note-textarea:focus-visible{outline:3px solid var(--blue);outline-offset:2px}
.step-guide-list{margin:6px 0 0;padding-left:20px;display:grid;gap:6px;line-height:1.5}
.ref-controls{display:flex;align-items:center; justify-content:space-between;gap:14px;flex-wrap:wrap;margin:20px 0}
.ref-search{flex:1;min-width:220px;border:1px solid var(--line);border-radius:9px;padding:10px 14px;font-size:15px;background:var(--surface,#fff);color:var(--ink)}
.formula-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.formula-card{border:1px solid var(--line);border-radius:14px;padding:20px;background:var(--surface,#fff);display:flex;flex-direction:column;gap:8px}
.formula-card-head{display:flex;align-items:center;justify-content:space-between;gap:10px}
.formula-card h2{font-size:18px;margin:0}
.ref-formula{font-size:22px;font-weight:750;color:var(--blue-dark);margin:2px 0;letter-spacing:-.4px;overflow-wrap:anywhere}
.formula-card p{font-size:14px;color:var(--muted);margin:0}
.supplement-card{grid-column:1/-1}
.supplement-body{display:grid;gap:8px;margin-top:4px}
.supplement-body p{color:var(--ink);line-height:1.65}
.review-toolbar{display:flex;gap:10px;flex-wrap:wrap;margin:18px 0 22px}
.review-unit-header{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:12px;flex-wrap:wrap}
.review-unit-header h2{font-size:19px;margin:0}
.backup-actions{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin-top:12px}
.import-label{display:inline-flex;align-items:center;cursor:pointer}
.frac{display:inline-grid;grid-template-rows:auto auto;vertical-align:middle;text-align:center;line-height:1.12;margin:0 .14em;font-size:.86em;font-weight:inherit}
.frac-num{padding:0 .2em .1em;border-bottom:1.7px solid currentColor;display:block}
.frac-sep{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.frac-den{padding:.1em .2em 0;display:block}
.formula,.ref-formula,.worked-example .equation{line-height:1.4}
.formula .frac,.ref-formula .frac,.worked-example .equation .frac{font-size:.82em;margin:0 .16em}
.formula .frac-num,.ref-formula .frac-num,.worked-example .equation .frac-num{border-bottom-width:2.1px;padding:0 .24em .13em}
.formula .frac-den,.ref-formula .frac-den,.worked-example .equation .frac-den{padding:.13em .24em 0}
.formula sub,.ref-formula sub,.worked-example .equation sub,.notation dt sub{font-size:.68em;line-height:0}
.circuit-manage-btn{border:0;outline:0;background:transparent;box-shadow:none;padding:4px 2px;font-size:13px;font-weight:600;color:var(--muted)}
.circuit-manage-btn:hover{color:var(--blue);background:transparent}
.circuit-manage-btn:focus,.circuit-manage-btn:focus-visible{outline:none;box-shadow:none}
@media(max-width:900px){.formula-grid{grid-template-columns:1fr}}