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.tutor-backdrop{position:fixed;inset:0;background:#152d3850;z-index:150}.tutor-panel{position:fixed;top:0;right:0;bottom:0;width:430px;max-width:100%;background:var(--surface);z-index:151;display:flex;flex-direction:column;box-shadow:-12px 0 40px #132d3925}.tutor-panel>header{display:flex;align-items:center;gap:12px;padding:20px;border-bottom:1px solid var(--line)}.tutor-symbol{display:grid;place-items:center;width:42px;height:42px;background:var(--sky-soft);color:var(--sky);border-radius:7px}.tutor-panel header>div{min-width:0}.tutor-panel header h2{font-size:18px}.tutor-panel header small{display:block;font-size:11px;color:var(--muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.tutor-panel header>button{margin-left:auto;flex:none}.tutor-toolbar{display:flex;justify-content:space-between;padding:6px 16px;border-bottom:1px solid var(--line)}.tutor-messages{flex:1;min-height:0;overflow:auto;padding:20px}.tutor-message{margin-bottom:22px;font-size:13px;overflow-wrap:anywhere}.tutor-message>b{display:block;color:var(--sky);font-size:10px;text-transform:uppercase;margin-bottom:8px}.tutor-message.user{padding:12px;background:var(--sky-soft);border-radius:6px}.tutor-message.user>b{color:var(--muted)}.tutor-message>div{white-space:pre-line;line-height:1.8}.tutor-message .math-display{font-size:15px;white-space:normal;overflow:auto}.tutor-empty{text-align:left;padding:10px 0}.tutor-empty>svg{width:35px;height:35px;color:var(--sky);margin-bottom:18px}.tutor-empty p{font-size:12px;color:var(--muted);margin-top:10px}.tutor-suggestions{display:grid;gap:8px;margin-top:20px}.tutor-suggestions button{background:var(--surface);border:1px solid var(--line);border-radius:5px;padding:12px;text-align:left;color:var(--ink);font-size:12px}.tutor-compose{display:flex;gap:10px;align-items:end;padding:14px 16px;border-top:1px solid var(--line)}.tutor-compose textarea{flex:1;min-width:0;resize:none;font-size:14px;min-height:70px}.tutor-compose .icon-button{width:42px;height:42px;margin-bottom:3px}.tutor-panel footer{display:flex;justify-content:space-between;align-items:center;padding:0 18px 12px;color:var(--muted);font-size:10px}.tutor-panel footer button{font-size:10px}.tutor-error{display:flex;gap:10px;padding:12px 18px;background:var(--coral-soft);color:var(--ink);font-size:12px;border-top:1px solid var(--line)}.tutor-error svg{flex:none;color:var(--coral)}.tutor-thinking{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--muted)}.tutor-thinking svg{animation:spin 1.5s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.tutor-unlock{padding:22px}.tutor-unlock label{display:block;margin:20px 0}.tutor-unlock p{font-size:12px;color:var(--muted);margin-top:20px}.tutor-history{overflow:auto;flex:1;padding:14px}.tutor-history button{display:flex;width:100%;text-align:left;gap:10px;align-items:center;padding:15px 5px;background:transparent;color:var(--ink);border-bottom:1px solid var(--line)}.tutor-history b{font-size:12px}.tutor-history small{margin-left:auto;white-space:nowrap;font-size:10px;color:var(--muted)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
@media(max-width:900px){.gym-modes{grid-template-columns:1fr}.gym-mode small{font-size:12px}.lab-layout{display:flex;flex-direction:column;gap:22px}.lab-side{display:block}.lab-stage{min-height:0}.prediction{margin-bottom:20px}}
@media(max-width:700px){.content{padding:22px 18px 105px}.page-heading h1{font-size:28px}.page-heading p{font-size:13px}.game-band{gap:12px;margin-bottom:14px}.level-emblem{width:52px;height:48px}.level-progress>span{font-size:11px}.streak-count b{font-size:21px}.daily-goals{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:22px}.daily-goal{gap:5px;flex:1;min-width:90px;flex-wrap:wrap;font-size:10px}.daily-goal>b{font-size:10px}.daily-goal small{margin-left:23px;font-size:10px}.daily-band{padding:20px}.daily-copy h2{font-size:25px}.daily-copy p{font-size:13px}.daily-meta{font-size:11px}.daily-copy .primary{width:100%;justify-content:center}.stats-band{gap:18px}.stats-band>div{padding:0}.stats-band>div:nth-child(even){padding-left:18px}.stats-band span{font-size:11px}.task b{font-size:14px}.task small{font-size:11px}.task-time{font-size:11px;white-space:nowrap}.task-icon{width:36px;height:36px}.task-number{display:none}.topic-map span{font-size:11px}.topic-map small{font-size:10px}.practice-modes .mode-item h2{font-size:17px}.practice-modes .mode-item p{font-size:12px}.activity-banner{padding:18px 0;gap:16px}.activity-symbol{width:60px;height:60px}.activity-banner h2{font-size:22px}.activity-banner p{font-size:11px}.gym-mode{padding:15px}.gym-mode b{font-size:15px}.gym-mode small{font-size:11px}.gym-question{padding:8px 0}.gym-question h2{font-size:23px}.gym-equation{font-size:21px;padding:28px 0}.formula-topic>summary>span{font-size:14px}.formula-topic>summary small{font-size:10px}.formula-row b{font-size:14px}.formula-row small{font-size:11px}.formula-big{font-size:20px}.mission-steps{gap:14px}.mission-steps>span{font-size:11px}.lab-grid{gap:12px}.lab-item-info h2{font-size:15px}.lab-item-info .eyebrow{font-size:9px}.lab-item-info>span:last-of-type{font-size:11px}.lab-thumbnail{height:130px}.lab-side h2{font-size:19px}.lab-control span{font-size:13px}.lab-control input[type=number]{font-size:16px}.lab-reading{font-size:13px}.question-origin{gap:7px;margin-bottom:14px}.question-origin small{width:100%;font-size:10px}.question-surface{padding-top:15px}.question-title{font-size:19px;line-height:1.8}.question-actions .primary,.question-actions .secondary{min-height:46px;font-size:13px}.answer-label input,.answer-label textarea,select{font-size:16px}.choices button{min-height:65px;font-size:14px}.round-top{font-size:12px}.tutor-panel{width:100%;top:0;bottom:0;height:100dvh}.tutor-panel>header{padding:15px 18px}.tutor-compose{padding-bottom:calc(14px + env(safe-area-inset-bottom))}.tutor-compose textarea{font-size:16px}.tutor-panel .math-inline{max-width:100%}.mobile-nav{height:calc(65px + env(safe-area-inset-bottom))}.mobile-nav a{font-size:10px}.mobile-nav a.active{background:var(--teal-soft)}.mobile-nav a.active svg{stroke-width:2.5}.question-origin small{line-height:1.7}.tutor-history b{max-width:210px;overflow-wrap:anywhere}}

/* Concept Lab: make the learning sequence legible before the diagram takes over. */
.lab-overview{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:28px;padding:24px 0;border-top:2px solid var(--teal);border-bottom:1px solid var(--line);margin-bottom:24px}.lab-overview h2{font-size:24px;margin:7px 0}.lab-overview p{max-width:680px;color:var(--muted);font-size:14px}.lab-next{border-left:1px solid var(--line);padding-left:24px;display:flex;flex-direction:column;justify-content:center;gap:12px}.lab-index-tools{display:flex;gap:12px;align-items:center;margin-bottom:20px}.lab-index-tools .topic-search{flex:1;min-width:180px}.lab-index-tools select{min-width:150px}.lab-item{min-width:0}.lab-item-info{min-width:0}.lab-card-state{font-variant-numeric:tabular-nums}.lab-task-note{font-size:14px;color:var(--muted);line-height:1.6;margin:8px 0 16px}.lab-task{min-width:0}.lab-complete-actions{border-top:1px solid var(--line);margin-top:18px;padding-top:18px}.lab-complete-actions small{display:block;color:var(--muted);font-size:12px;margin-top:8px}.lab-coach{border-top:2px solid var(--teal);padding-top:16px}.lab-coach h2{font-size:20px;margin:7px 0}.lab-coach p{font-size:14px;margin-bottom:12px}.lab-main>.lab-task{margin-bottom:18px}
@media(max-width:900px){.lab-overview{grid-template-columns:1fr;gap:16px}.lab-next{border-left:0;border-top:1px solid var(--line);padding:16px 0 0}.lab-index-tools{flex-wrap:wrap}.lab-index-tools .topic-search{flex-basis:100%}.lab-index-tools select{flex:1;min-width:0}.lab-main>.lab-task{order:-1}.lab-coach{margin-top:4px}}
@media(max-width:700px){.lab-overview{padding:20px 0;margin-bottom:18px}.lab-overview h2{font-size:22px;line-height:1.3}.lab-overview p{font-size:14px;line-height:1.65}.lab-index-tools{gap:8px;margin-bottom:14px}.lab-index-tools select{font-size:16px;width:calc(50% - 4px);min-width:0}.lab-item-info p{display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.lab-card-state{min-height:32px}.lab-main>.lab-task{margin-bottom:14px}.lab-task-note{font-size:14px}.lab-coach{padding-top:14px}.lab-coach p{font-size:14px}.lab-complete-actions{margin-top:14px;padding-top:14px}}
body.tutor-visible{overflow:hidden}.gym-equation .math-inline{overflow-x:auto;max-width:100%;vertical-align:middle}.gym-equation .katex{font-size:1.15em}.tutor-message{max-width:100%}
.button-icon{display:inline-grid;place-items:center;line-height:0;flex:0 0 auto}.button-icon svg{display:block}.primary,.secondary,.text-button,.menu-link{align-items:center}.primary,.secondary{justify-content:center}.mobile-section-nav{display:none}.print-booklet{max-width:190mm;margin:0 auto;color:#111;background:#fff;font-family:Arial,sans-serif}.print-cover{min-height:245mm;border:1px solid #222;padding:18mm 16mm;display:flex;flex-direction:column}.print-brand{font-size:10pt;font-weight:700;letter-spacing:.08em;border-bottom:2px solid #111;padding-bottom:5mm}.print-cover h1{font-size:24pt;margin:22mm 0 12mm}.print-cover>p{font-size:10pt}.print-fields{display:grid;gap:12mm;margin:12mm 0 18mm;font-size:11pt}.print-instructions{border:1px solid #222;padding:7mm;font-size:11pt;line-height:1.6}.print-instructions b{display:block;margin-bottom:3mm}.print-questions{padding-top:10mm}.print-question{break-inside:avoid;border-top:1px solid #777;padding:7mm 0 10mm}.print-question h2{font-size:13pt;font-weight:600;line-height:1.7;margin:0 0 6mm}.print-question h2 small{font-size:10pt;white-space:nowrap;font-weight:400}.print-part{margin:5mm 0 0 6mm}.print-part p{font-size:11pt;line-height:1.9;margin:3mm 0}.answer-lines{height:25mm;border-bottom:1px dotted #999;background:repeating-linear-gradient(to bottom,transparent 0,transparent 9mm,#d1d1d1 9.2mm,#d1d1d1 9.4mm)}.answer-lines.long{height:60mm}.print-footer{border-top:1px solid #777;padding:4mm 0;font-size:8pt;margin-top:8mm}.mock-upload-note{display:block;color:var(--muted);font-size:10px;margin-top:12px;line-height:1.5}
.upload-question-list{border-top:1px solid var(--line);margin-top:20px}.upload-question-row{display:flex;align-items:center;gap:15px;justify-content:space-between;border-bottom:1px solid var(--line);padding:16px 0}.upload-question-row>span{min-width:0}.upload-question-row b,.upload-question-row small{display:block;overflow-wrap:anywhere}.upload-question-row small{color:var(--muted);font-size:11px;margin-top:5px}.upload-question-row .secondary{flex:none}
@media(max-width:700px){.mobile-section-nav{display:flex;gap:4px;overflow-x:auto;padding:8px 14px;background:var(--surface);border-bottom:1px solid var(--line);scrollbar-width:none}.mobile-section-nav::-webkit-scrollbar{display:none}.mobile-section-nav a{display:flex;align-items:center;gap:5px;flex:none;padding:8px 9px;border-radius:5px;color:var(--muted);font-size:10px;white-space:nowrap}.mobile-section-nav a.active{background:var(--teal-soft);color:var(--teal);font-weight:700}.mobile-section-nav svg{width:15px;height:15px}.mobile-nav{gap:0;overflow:hidden;justify-content:stretch}.mobile-nav a{min-width:0;flex:1 1 25%;white-space:nowrap}.mobile-nav a span{font-size:9px}.primary,.secondary,.text-button{display:inline-flex;align-items:center;justify-content:center;gap:8px}.primary .button-icon,.secondary .button-icon,.text-button .button-icon{width:18px;height:18px}.page-heading>.primary .button-label,.page-heading>.secondary .button-label{display:none}.page-heading>.primary,.page-heading>.secondary{padding:0}.page-heading>.primary .button-icon,.page-heading>.secondary .button-icon{width:20px;height:20px}.question-actions .primary,.question-actions .secondary{min-height:46px}.mock-upload-note{font-size:10px}}
@media(min-width:701px){.mobile-section-nav{display:none}}
@media print{body{background:#fff!important}.print-booklet{max-width:none}.print-cover{min-height:250mm}.print-question{break-inside:avoid}.print-footer{position:fixed;bottom:0;left:0;right:0}}

/* Tutor composer: keep the conversation scrollable and the phone controls in view. */
.tutor-panel{min-height:0}
.tutor-panel>header,.tutor-toolbar,.tutor-panel footer,.tutor-error{flex:0 0 auto}
.tutor-messages{flex:1 1 auto;min-height:0;overflow:auto;overscroll-behavior:contain}
.tutor-compose{flex:0 0 auto;display:grid;gap:8px;align-items:stretch;background:var(--surface)}
.tutor-compose-row{display:flex;align-items:end;gap:8px;min-width:0}
.tutor-compose textarea{width:0;max-height:34dvh;overflow:auto}
.tutor-attach{position:relative;overflow:hidden;cursor:pointer}
.tutor-attach input{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer;padding:0;min-height:0}
.tutor-attachments{display:flex;gap:12px;overflow-x:auto;padding:4px 0;scrollbar-width:none}
.tutor-attachments::-webkit-scrollbar{display:none}
.tutor-attachment{display:flex;align-items:center;flex:0 0 98px;width:98px;height:54px}
.tutor-attachment img{display:block;width:54px;height:54px;object-fit:cover;border-radius:6px;outline:1px solid #0001}
.tutor-attachment .icon-button{position:static;width:44px;height:44px;min-height:44px;margin:0;background:var(--surface);color:var(--ink);border:0}
.tutor-compose-hint{color:var(--muted);font-size:10px;line-height:1.3}
.tutor-attachment-note{display:block;color:var(--muted);font-size:10px;margin:-4px 0 7px}
@media(max-width:700px){.tutor-panel{width:100%;height:100dvh;max-height:100svh;min-height:0}.tutor-panel>header{padding:14px 16px}.tutor-messages{padding:16px}.tutor-compose{padding:10px 16px max(10px,env(safe-area-inset-bottom));}.tutor-compose .icon-button{width:44px;height:44px;min-height:44px;margin-bottom:2px}.tutor-compose textarea{min-height:64px;font-size:16px}.tutor-panel footer{padding:0 16px 10px}.tutor-error{max-height:25svh;overflow:auto}}

/* Interaction polish: stable touch geometry, optical alignment and restrained motion. */
html{-webkit-font-smoothing:antialiased;scroll-behavior:smooth}
button,a,input,select,textarea{touch-action:manipulation}
button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:3px solid color-mix(in srgb,var(--teal) 42%,transparent);outline-offset:3px}
.primary,.secondary,.danger,.text-button,.icon-button,.mobile-section-nav a,.mobile-nav a{transition-property:transform,background-color,color,border-color,box-shadow,opacity;transition-duration:140ms;transition-timing-function:cubic-bezier(.2,0,0,1)}
.primary:active,.secondary:active,.danger:active,.text-button:active,.icon-button:active{transform:scale(.96)}
.mobile-section-nav{scroll-snap-type:x proximity;overscroll-behavior-x:contain;min-height:52px;contain:layout paint}
.mobile-section-nav a{min-height:44px;scroll-snap-align:start}
.mobile-section-nav a.active{box-shadow:inset 0 -2px var(--teal)}
.mobile-nav{padding-bottom:env(safe-area-inset-bottom);height:calc(70px + env(safe-area-inset-bottom));overscroll-behavior-x:contain;contain:layout paint}
.mobile-nav a{min-height:54px;min-width:0;padding:7px 4px 4px;gap:4px;scroll-snap-align:center}
.mobile-nav a svg{width:20px;height:20px;stroke-width:1.8}
.mobile-nav a.active{box-shadow:inset 0 2px var(--teal)}
.mobile-nav a.active svg{stroke-width:2.2}
.button-icon{width:20px;height:20px;align-items:center;justify-content:center}
.button-icon svg{width:18px;height:18px}
.primary,.secondary,.danger{min-height:44px}
.page-heading>.primary,.page-heading>.secondary{min-width:44px}
.stats-band b,.exam-clock,.result-number,.test-result>b{font-variant-numeric:tabular-nums}
.question-title,h1,h2,h3{ text-wrap:balance }
.small-muted,p{ text-wrap:pretty }
.lab-item,.mock-item,.mode-item,.choices button,.prediction-options button{box-shadow:0 1px 1px #142b3510}
.lab-item:hover,.mock-item:hover,.mode-item:hover{transform:translateY(-2px);transition:transform 150ms cubic-bezier(.2,0,0,1),box-shadow 150ms cubic-bezier(.2,0,0,1)}
.upload-question-row{min-height:76px}
.upload-question-row .secondary{min-height:44px}
.ai-diagnostics{display:grid;gap:10px;max-width:860px;margin-top:10px}
.ai-check{display:grid;grid-template-columns:44px minmax(0,1fr) auto;align-items:center;gap:14px;text-align:left;padding:14px 16px;min-height:72px;background:var(--surface);border:1px solid var(--line);border-radius:8px;color:var(--ink)}
.ai-check:hover{border-color:var(--teal);box-shadow:0 4px 16px #142b3514}
.ai-check-icon{display:grid;place-items:center;width:40px;height:40px;border-radius:8px;background:var(--teal-soft);color:var(--teal)}
.ai-check b,.ai-check small{display:block}.ai-check small{color:var(--muted);font-size:11px;margin-top:3px}.ai-check i{font-style:normal;font-size:11px;color:var(--muted);font-variant-numeric:tabular-nums}.ai-check.passed i{color:var(--teal)}.ai-check.failed i{color:var(--coral)}.ai-diagnostics-note{margin-top:18px;max-width:700px}
.recovery-warning{border-left:3px solid var(--gold);padding-left:16px;background:var(--gold-soft)}

/* Study workspace: readable type, quiet surfaces and task-first phone layouts. */
@media screen{
 html{--bg:#f6f8f7;--surface:#fff;--sidebar:#fff;--ink:#202925;--muted:#5e6d65;--line:#dce4df;--teal:#126b53;--teal-soft:#e7f2eb;--sky:#266e9b;--sky-soft:#eaf3fa;--coral:#b64c46;--coral-soft:#fcefed;--gold:#9a6a17;--gold-soft:#fbf4e2;--pink:#a2486d;--pink-soft:#f8edf2;--grid:#e5ebe7;--shadow:0 2px 8px #2029250a}
 html[data-theme=dark]{--bg:#171a18;--surface:#202521;--sidebar:#1d221e;--ink:#edf2ee;--muted:#adbbb1;--line:#3b453d;--teal:#8ed9b2;--teal-soft:#253c2e;--sky:#97c6ec;--sky-soft:#263640;--coral:#f0a09a;--coral-soft:#402c2c;--gold:#e8c67f;--gold-soft:#3e3525;--pink:#e8a2c2;--pink-soft:#3d2b35;--grid:#333e36;--shadow:none}
 body{font-family:Studio,'Segoe UI',Arial,sans-serif;font-size:15px;line-height:1.6}
 h1{font-size:32px;font-weight:750}h2{font-weight:650}h1,h2,h3{letter-spacing:0}
 .shell{grid-template-columns:224px minmax(0,1fr)}
 .sidebar{padding:28px 18px;height:100dvh;overflow-y:auto}.sidebar>.brand,.sidebar>.qualification,.sidebar-bottom{flex-shrink:0}.sidebar nav{min-height:0;overflow-y:auto;grid-auto-rows:minmax(48px,max-content);align-content:start}.brand{font-size:22px}.brand img,.mobile-brand img{filter:none}.qualification{font-size:11px;margin:18px 0 32px}
 .sidebar nav a{font-size:14px;min-height:48px;padding:12px}.sidebar nav a.active{box-shadow:none;background:var(--teal-soft)}
 .sidebar-bottom>a{min-height:44px;padding:10px 12px}.countdown{border:0;border-top:1px solid var(--line);border-radius:0;padding:18px 10px}.countdown>span{font-size:11px}
 .topbar{border-top:0;height:72px;padding:0 36px}.top-crumb{font-size:13px}.top-actions .icon-button,.icon-button{width:44px;min-height:44px}.xp{font-size:12px;margin-right:8px}
 .content{max-width:1360px;padding:36px 36px 72px}.page-heading{margin-bottom:28px;align-items:center}.page-heading p{font-size:14px;max-width:none}
 .primary,.secondary,.danger,.text-button{font-size:14px;min-height:44px;font-weight:600;box-shadow:none;border-radius:6px}
 .primary{background:var(--teal);color:#fff;padding:11px 18px}.primary:active{transform:scale(.96);box-shadow:none}.secondary:hover{background:var(--teal-soft)}
 html[data-theme=dark] .primary{color:#17261e}.icon-button:hover{background:var(--teal-soft);color:var(--teal)}
 .eyebrow{font-size:11px;font-weight:650;color:var(--muted)}.small-muted{font-size:14px;line-height:1.7}
 .today-layout{gap:30px;grid-template-columns:minmax(0,1fr) 244px}.right-rail{padding-left:24px}.right-rail h2{font-size:20px}.right-rail section{margin-bottom:24px;padding-bottom:24px}
 .daily-band{border:0;border-top:2px solid var(--teal);border-bottom:1px solid var(--line);border-radius:0;padding:28px 0;background:transparent;grid-template-columns:minmax(0,1fr) minmax(170px,.8fr);gap:24px;overflow:visible}
 .daily-copy h2{font-size:30px;line-height:1.2;max-width:370px;margin:16px 0 12px}.daily-copy p{font-size:14px;max-width:360px;line-height:1.7}.daily-copy .primary{margin-top:2px}.daily-meta{font-size:12px;gap:18px;margin-top:22px}.daily-meta svg{width:16px;height:16px}
 .daily-graph{background:transparent;border-radius:0}.daily-graph svg{max-height:260px}.stats-band{padding:22px 0;gap:12px}.stats-band span{font-size:12px}.stats-band b{font-size:28px}.stats-band small{font-size:14px}
 .section{padding-top:28px}.section-heading{align-items:center;flex-wrap:wrap;margin-bottom:16px}.section-heading h2{font-size:20px}.section-heading>span{font-size:12px;max-width:none}.text-link{font-size:13px;min-height:44px}
 .task{min-height:84px;gap:14px}.task b{font-size:15px}.task small{font-size:13px;line-height:1.5;margin-top:4px}.task-number,.task-time{font-size:12px}.task-icon{width:40px;height:40px}.task>svg{display:block}
 .notebook-details{border-top:1px solid var(--line);margin-top:24px}.notebook-details>summary{display:flex;justify-content:space-between;align-items:center;gap:12px;min-height:56px;list-style:none;font-size:14px;font-weight:600}.notebook-details>summary>span{display:flex;align-items:center;gap:10px}.notebook-details[open]>summary{margin-bottom:14px}.notebook-details[open]>summary>svg:last-child{transform:rotate(180deg)}
 .topic-map span{font-size:13px}.topic-map small{font-size:11px}.topic-map a{min-height:76px}.game-band{padding-top:12px}.game-band .level-emblem{height:44px}.daily-goal{font-size:12px}.daily-goals{margin-bottom:18px}
 .focus-topics a{min-height:48px;font-size:14px}.day-grid span{font-size:12px}.mini-challenge p{font-size:16px}.paper-note>div{font-size:14px}.paper-note small{font-size:12px}
 .practice-start{display:grid;grid-template-columns:minmax(0,1fr) 160px;gap:28px;border-top:2px solid var(--teal);border-bottom:1px solid var(--line);padding:28px 0}.practice-start h2{font-size:28px;margin:12px 0}.practice-start p{font-size:15px;color:var(--muted);max-width:540px}.practice-start .question-actions{margin:20px 0 16px}.session-meta{font-size:13px;color:var(--muted)}.session-meta>span{padding:0 8px}
 .practice-mark{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;color:var(--teal);background:var(--teal-soft);border-radius:6px}.practice-mark>svg{width:36px;height:36px}.practice-mark>span{font-size:24px;font-variant-numeric:tabular-nums}.practice-mark>span>span{color:var(--muted);font-size:16px}
 .practice-modes{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 24px}.practice-modes .mode-item{display:flex;align-items:center;gap:16px;border:0;border-bottom:1px solid var(--line);border-radius:0;padding:22px 0;background:transparent;box-shadow:none;min-width:0}.mode-item:hover{transform:none;background:var(--teal-soft)}.practice-modes .mode-icon{margin:0;width:44px;height:44px;flex:none;background:var(--sky-soft);color:var(--sky)}.practice-modes .mode-item:nth-child(2) .mode-icon{background:var(--gold-soft);color:var(--gold)}.practice-modes .mode-item:nth-child(3) .mode-icon{background:var(--pink-soft);color:var(--pink)}.practice-modes .mode-item:nth-child(4) .mode-icon{background:var(--coral-soft);color:var(--coral)}.practice-modes .mode-item>div{min-width:0;flex:1}.practice-modes .mode-item h2{font-size:17px;min-height:0;margin:0}.practice-modes .mode-item p{font-size:13px;line-height:1.5;min-height:0;margin:5px 0 7px}.practice-modes .mode-item>div>span{font-size:12px;color:var(--muted)}
 .topic-search{display:flex;align-items:center;gap:8px;color:var(--muted)}.topic-search input{width:220px;font-size:15px;background:var(--surface)}.topic-search svg{width:18px}.topic-browser{grid-template-columns:repeat(2,minmax(0,1fr));gap:0 24px}.practice-topic{border-bottom:1px solid var(--line);min-width:0}.practice-topic[hidden]{display:none}.topic-browser .practice-topic>a{border:0;min-height:74px;padding:16px 0}.topic-browser b{font-size:15px}.topic-browser small{font-size:12px}.topic-browser .topic-lab-link{min-height:44px;justify-content:flex-start;gap:8px;font-size:12px;color:var(--sky);padding:0 0 12px}.topic-lab-link svg{width:16px;height:16px}.topic-lab-link svg:last-child{margin-left:auto}
 .activity-banner{border-bottom:1px solid var(--line);padding:0 0 24px;margin-bottom:12px}.activity-banner h2{font-size:24px}.activity-banner p{font-size:14px}.activity-symbol{width:56px;height:56px;border-radius:6px;box-shadow:none}
 .gym-mode{border:0;border-bottom:1px solid var(--line);border-radius:0;box-shadow:none;background:transparent;padding:22px 0}.gym-mode b{font-size:17px}.gym-mode small{font-size:13px}.gym-mode:hover{transform:none;background:var(--teal-soft)}.gym-mode .mode-icon{width:44px;height:44px;box-shadow:none}.gym-modes{gap:0 24px}.formula-topic>summary{font-size:16px;min-height:64px}.formula-topic>summary>span{font-size:16px}.formula-topic>summary small{font-size:12px}.formula-row summary{min-height:64px}.formula-row b{font-size:15px}.formula-row small{font-size:12px}.formula-expanded p{font-size:14px}.gym-equation{padding:24px 0}.gym-question h2{font-size:26px}
 .lab-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.lab-item{border:1px solid var(--line);border-radius:6px;box-shadow:none}.lab-item:hover{transform:none;border-color:var(--teal);box-shadow:none}.lab-thumbnail{height:168px;background:var(--teal-soft);border-bottom:1px solid var(--line)}.lab-item[data-colour="1"] .lab-thumbnail{background:var(--sky-soft)}.lab-item[data-colour="2"] .lab-thumbnail{background:var(--gold-soft)}.lab-item[data-colour="3"] .lab-thumbnail{background:var(--pink-soft)}.lab-item-info{padding:18px}.lab-item-info h2{font-size:19px;min-height:0;margin:7px 0}.lab-item-info p{font-size:14px;line-height:1.6;color:var(--muted);margin-bottom:14px}.lab-item-info>span:last-of-type{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--teal)}.mission-dots{margin-top:14px}
 .crumb{min-height:44px;margin-bottom:12px;font-size:14px}.mission-steps{gap:24px;margin-bottom:24px}.mission-steps>span{font-size:13px}.lab-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;align-items:start}.lab-stage{border-radius:6px;min-height:0;aspect-ratio:1.5;display:grid;align-items:center;background:var(--surface)}.lab-stage svg{max-height:100%;width:100%}.lab-reading{font-size:15px;min-height:0;padding:16px 0}.lab-reading[hidden]{display:none}
 .lab-side{display:flex;flex-direction:column;gap:18px}.lab-side h2{font-size:20px;line-height:1.5;margin:12px 0 16px}.prediction{border:0;margin:0;padding:0}.prediction-options{gap:10px}.prediction-options button{font-size:15px;min-height:48px;border-radius:6px;box-shadow:none}.lab-controls{border-top:1px solid var(--line);padding-top:20px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 22px}.lab-controls .lab-modes,.lab-controls>.primary{grid-column:1/-1}.lab-controls>.primary{justify-self:start}.lab-control{font-size:14px}.lab-control input[type=number]{font-size:16px;width:80px;min-height:44px}.lab-control input[type=range]{min-height:44px;cursor:pointer}.lab-control input[type=range]::-webkit-slider-thumb{width:24px;height:24px}.lab-modes{margin:0 0 20px;min-height:44px}.segmented button{min-height:44px;font-size:14px}.mission-message{font-size:14px;line-height:1.6}
 .question-title{font-size:22px;line-height:1.8;margin:16px 0 24px}.question-origin small{font-size:12px}.source-tag{font-size:12px;min-height:40px}.difficulty{font-size:12px}.question-actions{gap:12px}.answer-label{font-size:14px}.answer-label input{width:min(100%,440px);font-size:17px}.choices button{font-size:16px;min-height:64px;box-shadow:none}.choice-letter{width:30px;height:30px;font-size:13px}.solution-steps{font-size:16px;line-height:1.7}.feedback,.hint{font-size:15px}.round-top{font-size:13px;margin-bottom:22px}.question-aside .eyebrow{font-size:11px}.rubric,.distractors{font-size:14px}.rubric summary,.distractors summary{min-height:44px}.answer-review summary{min-height:56px;font-size:15px}
 .question-index{gap:8px}.question-index button{width:44px;height:44px;font-size:14px}.mock-grid{gap:20px}.mock-item{border-radius:6px;box-shadow:none;padding:24px}.mock-item h2{font-size:24px}.mock-item p{font-size:14px}.mock-facts{font-size:13px}.mock-upload-note{font-size:12px}
 .work-form textarea,.transcription textarea,.followup textarea{font-size:16px}.work-form>label,.transcription>label{font-size:15px}.work-form>details>summary{min-height:44px}.upload-zone{background:var(--sky-soft);border-color:var(--sky)}.upload-zone span{font-size:13px}.image-previews button{width:44px;min-height:44px}.image-previews img{outline:1px solid rgb(0 0 0 / .1);outline-offset:-1px}html[data-theme=dark] .image-previews img{outline-color:rgb(255 255 255 / .1)}.unlock-form{padding-top:4px}.unlock-form h2{font-size:23px}.unlock-form label{font-size:14px}.unlock-form input{font-size:16px}
 .tutor-panel{width:min(480px,100%)}.tutor-message{font-size:15px}.tutor-message>b{font-size:12px}.tutor-compose textarea{font-size:16px}.tutor-suggestions button{min-height:44px;font-size:14px}.tutor-unlock{overflow:auto}.tutor-unlock input{display:block;width:100%;font-size:16px;margin-top:8px}.tutor-error{font-size:14px}.tutor-empty p{font-size:14px}.tutor-history button{min-height:56px}.tutor-compose .icon-button{width:44px;height:44px}.settings-section p{font-size:14px}.settings-fields label{font-size:14px}.check-row{min-height:44px}.ai-check small,.ai-check i{font-size:13px}
 @media(hover:hover){.choices button:not(:disabled):hover,.prediction-options button:hover{border-color:var(--teal)}.task:hover,.practice-topic>a:hover{background:var(--teal-soft)}}
 @media(max-width:1100px){.shell{grid-template-columns:196px minmax(0,1fr)}.content{padding:28px 24px 64px}.topbar{padding:0 24px}.today-layout{grid-template-columns:1fr}.today-layout>.right-rail{border-left:0;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}.daily-band{grid-template-columns:minmax(0,1fr) minmax(170px,.7fr)}.daily-graph{display:block}.lab-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.lab-layout{grid-template-columns:1fr}.lab-side{display:contents}.lab-side>.prediction,.lab-side>.mission-goal{grid-row:1}.lab-side>.primary,.lab-side>.text-button{justify-self:start}.lab-main{min-width:0}.lab-stage{max-height:420px}.lab-side h2{font-size:20px}}
 @media(max-width:700px){
  .shell{display:block}.topbar{height:64px;padding:0 16px;gap:8px}.top-actions{gap:4px}.top-actions .icon-button{width:44px;min-height:44px;border:0;background:transparent}.top-actions .xp{display:none}.mobile-brand{font-size:18px;gap:8px}.mobile-brand img{width:30px;height:30px}
  .mobile-section-nav{position:static;min-height:52px;padding:4px 12px;border-bottom:1px solid var(--line);backdrop-filter:none;background:var(--surface)}.mobile-section-nav a{font-size:13px;min-height:44px;padding:8px 12px;border-radius:4px}.mobile-section-nav svg{width:16px;height:16px}.mobile-section-nav a.active{box-shadow:none}
  .content{padding:24px 18px calc(100px + env(safe-area-inset-bottom))}.page-heading{align-items:flex-start;margin-bottom:24px;gap:12px}.page-heading h1{font-size:28px}.page-heading p{font-size:14px;line-height:1.6;max-width:100%}.page-heading>.primary,.page-heading>.secondary{width:44px;height:44px;min-width:44px;padding:0}
  .mobile-nav{height:calc(68px + env(safe-area-inset-bottom));background:var(--surface);backdrop-filter:none}.mobile-nav a{font-size:12px;padding:6px 4px;gap:4px}.mobile-nav a span{font-size:12px;max-width:none}.mobile-nav a.active{background:transparent;box-shadow:inset 0 2px var(--teal)}.mobile-nav a.active svg{stroke-width:2}.mobile-nav a svg{stroke-width:2}.mobile-brand{min-height:44px}.content:focus{outline:none}
  .daily-band{grid-template-columns:minmax(0,1fr) 100px;gap:8px;padding:22px 0}.daily-copy h2{font-size:26px;max-width:300px}.daily-copy p{font-size:14px;max-width:300px}.daily-copy .primary{width:auto;min-height:48px}.daily-meta{font-size:12px;gap:10px;margin-top:16px;flex-wrap:wrap}.daily-graph{align-self:start;opacity:1;overflow:hidden;margin-top:36px}.daily-graph svg{min-width:180px;width:180px;transform:translateX(-40px);max-height:160px}.daily-band .daily-copy{grid-column:1/-1}.daily-band .daily-graph{display:none}
  .stats-band{grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;padding:20px 0}.stats-band>div,.stats-band>div:nth-child(even){border:0;padding:0}.stats-band span{font-size:11px;line-height:1.5;min-height:34px}.stats-band b{font-size:24px;margin-top:4px}.stats-band small{font-size:12px;display:block}.section{padding-top:24px}.section-heading h2{font-size:19px}.section-heading>span{font-size:12px;text-align:left}.task{gap:10px;padding:18px 0}.task-icon{width:36px;height:36px}.task-number{display:none}.task b{font-size:15px}.task small{font-size:13px}.task-time{font-size:12px}.task>svg{display:none}
  .today-layout>.right-rail{grid-template-columns:1fr;gap:12px;margin-top:28px}.right-rail section{margin-bottom:0}.notebook-details{margin-top:20px}.notebook-details>summary{font-size:14px}.topic-map{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.topic-map span{font-size:12px}.daily-goals{grid-template-columns:1fr;gap:12px}.day-grid{max-width:320px}
  .practice-start{grid-template-columns:minmax(0,1fr) 72px;gap:12px;padding:24px 0}.practice-start h2{font-size:25px}.practice-start p{font-size:14px}.practice-start .question-actions{margin:18px 0 12px;flex-direction:column;align-items:flex-start}.practice-start .primary{min-height:48px}.practice-mark{background:transparent;justify-content:flex-start;padding-top:34px;gap:14px}.practice-mark>svg{width:28px;height:28px}.practice-mark>span{font-size:17px}.session-meta{font-size:12px}
  .practice-modes{grid-template-columns:1fr;gap:0}.practice-modes .mode-item{padding:20px 0;gap:14px}.practice-modes .mode-item h2{font-size:17px}.practice-modes .mode-item p{font-size:14px}.practice-modes .mode-item>div>span{font-size:12px}.topic-browser{grid-template-columns:1fr;gap:0}.topic-search{width:100%}.topic-search input{width:100%;min-width:0}.topic-browser b{font-size:15px}.topic-browser small{font-size:12px}.topic-browser .topic-lab-link{font-size:13px;padding-left:32px}
  .activity-banner{gap:14px}.activity-banner h2{font-size:23px}.activity-banner p{font-size:13px}.activity-symbol{width:48px;height:48px}.gym-mode{padding:20px 0}.gym-mode b{font-size:17px}.gym-mode small{font-size:14px}.gym-question h2{font-size:24px}.formula-topic>summary>span{font-size:15px}.formula-topic>summary small{font-size:12px}.formula-row b{font-size:15px}.formula-row small{font-size:12px}.formula-expanded{padding-left:0}.gym-equation{font-size:22px}
  .lab-grid{grid-template-columns:1fr;gap:18px}.lab-item{display:grid;grid-template-columns:112px minmax(0,1fr);align-items:stretch}.lab-thumbnail{height:100%;min-height:180px;border:0;border-right:1px solid var(--line)}.lab-thumbnail svg{width:180px;max-width:none;transform:translateX(-34px)}.lab-item-info{padding:16px}.lab-item-info .eyebrow{font-size:11px}.lab-item-info h2{font-size:18px;margin:6px 0}.lab-item-info p{font-size:13px;margin-bottom:10px}.lab-item-info>span:last-of-type{font-size:13px}.mission-steps{justify-content:space-between;gap:8px;margin-bottom:20px}.mission-steps>span{font-size:13px}.lab-layout{gap:18px}.lab-stage{aspect-ratio:1.3;max-height:none}.lab-reading{font-size:14px}.lab-side h2{font-size:20px;margin-top:8px}.lab-controls{grid-template-columns:1fr;gap:0;padding-top:18px}.lab-control{margin-bottom:20px}.lab-control>span{font-size:14px}.lab-control input[type=number]{font-size:16px;width:84px}.lab-controls>.primary{width:100%;min-height:48px}.lab-side>.primary{width:100%;min-height:48px}.prediction-options button{font-size:15px;min-height:48px}.prediction .primary{min-height:48px}.lab-side .text-button{min-height:44px}
  .question-surface{padding-top:0}.question-title{font-size:20px;line-height:1.75}.question-origin{margin-bottom:12px}.question-origin small{font-size:12px;line-height:1.6}.question-actions{gap:10px}.question-actions>.primary{min-height:48px}.question-actions .primary,.question-actions .secondary{font-size:14px}.choices button{font-size:16px;padding:14px;gap:12px}.choice-letter{font-size:13px}.answer-label input,.answer-label textarea{font-size:16px;width:100%}.round-top{font-size:13px;gap:10px}.solution-steps{font-size:15px}.feedback,.hint{font-size:14px}.rubric summary,.distractors summary{font-size:14px}.question-index button{width:44px;height:44px}.exam-toolbar{flex-wrap:wrap;gap:14px}.exam-toolbar>span{max-width:none;font-size:13px}.exam-toolbar .primary,.exam-toolbar .secondary{font-size:13px;min-height:44px}.exam-toolbar>div{display:flex;gap:10px}.mock-item{padding:20px}.mock-facts{font-size:13px;flex-wrap:wrap}.mock-item .question-actions>*{flex:1 1 auto}.mock-upload-note{font-size:12px}.answer-review summary{font-size:14px}
  .work-form textarea,.transcription textarea,.followup textarea,.work-form>details textarea{font-size:16px}.work-source .eyebrow{font-size:11px}.work-source .text-button{font-size:13px}.work-layout>.right-rail{gap:16px}.image-previews button{width:44px;min-height:44px}.tutor-panel{width:100%;height:100dvh}.tutor-messages{padding:18px}.tutor-message{font-size:15px}.tutor-panel header small{font-size:12px}.tutor-compose{padding-bottom:calc(12px + env(safe-area-inset-bottom))}.tutor-panel footer{font-size:12px}.tutor-panel footer button{font-size:13px}.tutor-history b{font-size:14px}.tutor-error{max-height:25dvh;overflow:auto}.ai-check{grid-template-columns:40px minmax(0,1fr);gap:12px}.ai-check i{grid-column:2;overflow-wrap:anywhere}.theme-choice>span{font-size:13px}.settings-fields input{font-size:16px}
  #toast{bottom:calc(80px + env(safe-area-inset-bottom));font-size:14px}.source-item b{font-size:14px}.source-item small{font-size:12px}.source-search input{font-size:16px}
 }
 @media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
 .reduced-motion{scroll-behavior:auto}
 .success-pop{animation:none}
 .assessment-summary{font-size:16px;margin-bottom:24px}.submitted-working{white-space:pre-line;font-size:15px;line-height:1.8;margin:12px 0 24px}.marking-result>details>summary{min-height:44px;font-size:15px;font-weight:600}.marking-result>details>ul{font-size:15px;line-height:1.7}
}

@media(max-width:700px){
 body{padding-bottom:env(safe-area-inset-bottom)}
 .topbar{position:sticky;top:0;z-index:90;box-shadow:0 1px 0 #132d3910}
 .mobile-section-nav{position:static;z-index:80;padding:4px 12px;background:var(--surface);backdrop-filter:none}
 .mobile-section-nav a{font-size:13px;padding:8px 12px}
 .content{padding-bottom:calc(112px + env(safe-area-inset-bottom))}
 .mobile-nav{backdrop-filter:none;background:var(--surface)}
 .mobile-nav a{font-size:12px}
 .mobile-nav a span{max-width:none}
 .question-actions{align-items:stretch}
 .question-actions>.primary,.question-actions>.secondary{min-height:46px}
}

@media screen{
 .written-assessment{border-top:1px solid var(--line);margin-top:22px;padding:20px 0}
 .written-assessment .section-heading{margin-bottom:14px}.written-assessment .section-heading>span{font-size:12px;color:var(--muted)}
 .written-upload-actions{display:flex;gap:12px;flex-wrap:wrap;align-items:center}.written-assessment .image-previews{margin-top:16px}
 .written-unlock{display:flex;gap:12px;align-items:end;flex-wrap:wrap;margin-top:18px}.written-unlock label{font-size:14px}.written-unlock input{display:block;margin-top:8px;width:240px;font-size:16px}
 .written-assessment>.answer-label{margin-top:18px}.written-assessment>.primary{margin-top:12px}.written-report{border-top:1px solid var(--line);margin-top:24px;padding-top:24px}.written-assessment .notice-error{margin-top:14px}
 .tutor-panel{top:var(--tutor-top,0px);bottom:auto;height:var(--tutor-height,100dvh);max-height:var(--tutor-height,100dvh);overflow:hidden}
 .tutor-panel header>div{flex:1}.tutor-symbol{flex:none}.tutor-history,.tutor-unlock{min-height:0;overscroll-behavior:contain}
 .tutor-error{max-height:20%;overflow:auto}.tutor-compose textarea{min-height:64px;max-height:110px}
 .tutor-attach:focus-within{outline:2px solid var(--teal);outline-offset:3px}
 .tutor-panel[data-compact]>header{padding:8px 12px}.tutor-panel[data-compact] .tutor-toolbar{padding:0 12px}.tutor-panel[data-compact] .tutor-messages{padding:8px 12px}
 .tutor-panel[data-compact] .tutor-compose{padding:8px 12px;gap:4px}.tutor-panel[data-compact] .tutor-compose textarea{height:64px;min-height:64px}
 .tutor-panel[data-compact] footer{padding-bottom:4px}.tutor-panel[data-compact] .tutor-error{max-height:50px;padding:8px 12px}
 html[data-theme=dark] .tutor-attachment img{outline-color:rgb(255 255 255 / .1)}
 @media(max-height:550px){
  .tutor-panel>header{padding:8px 12px}.tutor-toolbar{padding:0 12px}.tutor-messages{padding:8px 12px}
  .tutor-compose{padding:8px 12px;gap:4px}.tutor-compose textarea{height:64px;min-height:64px}
  .tutor-panel footer{padding-bottom:4px}.tutor-error{max-height:50px;padding:8px 12px}
 }
}

/* A4 print document: page numbers are supplied by the browser, with no fixed footer overlap. */
@page{size:A4 portrait;margin:15mm 15mm 17mm;@bottom-center{content:counter(page);font-family:Arial,Helvetica,sans-serif;font-size:8pt;color:#555}}
@media print{
 html,body{background:#fff!important;color:#111!important}
 .skip,#toast{display:none!important}
 body{font-family:Arial,Helvetica,sans-serif;font-size:10.5pt;line-height:1.45}
 .print-booklet{width:auto;max-width:none;margin:0;color:#111;background:#fff}
 .print-cover{min-height:0;height:250mm;border:1.2pt solid #111;padding:14mm 15mm;break-after:page;display:block}
 .print-brand{font-size:9pt;letter-spacing:.12em;padding-bottom:4mm;border-bottom:1.5pt solid #111}
 .print-cover>p{font-size:9pt;margin-top:5mm}
 .print-cover h1{font-size:22pt;line-height:1.15;margin:24mm 0 14mm}
 .print-fields{display:grid;gap:9mm;margin:0 0 16mm;font-size:10.5pt}
 .print-instructions{padding:6mm;border:1pt solid #111;font-size:9.5pt;line-height:1.5}
 .print-instructions b{display:inline-block;margin:0 18mm 4mm 0}
 .print-instructions p{margin-top:4mm}
 .print-questions{padding-top:0}
 .print-question{border-top:1pt solid #555;padding:6mm 0 0;margin:0;break-inside:avoid}
 .print-question h2{font-size:11pt;line-height:1.5;margin:0 0 4mm;font-weight:600}
 .print-question h2 small{font-size:9pt;margin-left:3mm}
 .print-part{margin:5mm 0 0 7mm;break-inside:avoid}
 .print-part>b{font-size:10pt}
 .print-part p{font-size:10pt;line-height:1.55;margin:2mm 0 3mm}
 .answer-lines{height:30mm;background:linear-gradient(to bottom,transparent 0,transparent calc(100% - .2mm),#b8b8b8 calc(100% - .2mm),#b8b8b8 100%);background-size:100% 8mm;border-bottom:0}
 .answer-lines.long{height:68mm}
 .print-footer{position:static;border-top:1pt solid #555;padding:3mm 0 0;margin-top:7mm;font-size:7.5pt;break-before:avoid}
 .print-footer{font-size:0}.print-footer:after{content:'Maths B Studio | Unofficial practice material';font-size:7.5pt}.print-footer .page-number{display:none}
 .math-display{break-inside:avoid}
}