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a{color:#fff}
@media(max-width:1050px){.sidebar{transform:translateX(-100%);transition:.25s}.sidebar.open{transform:none;box-shadow:30px 0 80px rgba(0,0,0,.3)}main{margin:0}.menu-button{display:grid}.hero-grid{grid-template-columns:1fr}.hero-visual{max-width:620px;width:90%;margin:auto}.lab-layout,.bonus-tools,.studio-grid{grid-template-columns:1fr}.mission-list{grid-template-columns:repeat(2,1fr)}.matrix-workbench{grid-template-columns:1fr}.matrix-result-zone{min-height:230px;margin-top:40px}.lesson-grid{grid-template-columns:repeat(3,1fr)}}
@media(max-width:720px){.page{padding:58px 20px}.topbar{padding:0 16px}.pill-button#resetProgress{display:none}.hero{padding-top:45px}.hero-grid{min-height:auto}.hero-visual{min-height:330px;margin-top:30px}.metric-row{grid-template-columns:repeat(2,1fr);gap:25px}.metric-row div:nth-child(2){border:0}.metric-row div:nth-child(3){padding-left:0}.split-heading{align-items:flex-start;flex-direction:column}.progress-ring{width:86px;height:86px}.explain-card{grid-template-columns:46px 1fr;padding:20px}.equation-box{grid-column:1/-1;border-left:0;border-top:1px solid #42536e;padding:18px 0 0}.mission-list{grid-template-columns:1fr}.concept-strip{grid-template-columns:1fr}.matrix-input-zone{gap:10px;flex-wrap:wrap}.matrix-grid{grid-template-columns:repeat(2,52px)}.matrix-grid input{width:52px}.matrix-facts{grid-template-columns:repeat(2,1fr)}.lesson-grid{grid-template-columns:repeat(2,1fr)}.duck{opacity:.35}footer{align-items:flex-start;flex-direction:column;gap:12px}}
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/* Instructional workflow */
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@media(max-width:1050px){.method-workbench{grid-template-columns:1fr}.method-lesson{min-height:500px}}
@media(max-width:720px){.principle-row{grid-template-columns:1fr}.challenge-card{grid-template-columns:46px 1fr;padding:20px}.challenge-actions{grid-column:1/-1;flex-direction:row}.concept-strip.detailed{grid-template-columns:1fr}.method-lesson{min-height:590px}.answer-area input{min-width:100%}}

/* Dyslexia-friendly reading system */
.panel{min-width:0}
.footer-copy{display:grid;gap:3px;text-align:center}.footer-copy small{color:#9eacc0;font-size:calc(10px * var(--reader-scale));line-height:1.5}
:root{--reader-scale:1;--reader-line:1.72;--reader-font:Verdana,Tahoma,"Segoe UI",Arial,sans-serif}
html[data-reading-size="large"]{--reader-scale:1.12}
html[data-reading-size="extra"]{--reader-scale:1.25}
html{scroll-padding-top:88px}
body{font-family:var(--reader-font);font-size:calc(16px * var(--reader-scale));font-weight:400;line-height:var(--reader-line);letter-spacing:.015em;word-spacing:.08em}
p,li,label,input,button{line-height:var(--reader-line)}
p{max-width:68ch}
h1,h2,h3,h4,strong,b{letter-spacing:0;word-spacing:.03em}
h1{font-size:clamp(calc(43px * var(--reader-scale)),5.3vw,78px);line-height:1.12;letter-spacing:-.025em}
h1 em{display:block;font-family:var(--reader-font);font-style:normal;font-weight:800;line-height:1.12}
em,i{font-style:normal}
.eyebrow,.micro-label{text-transform:none;letter-spacing:.045em;font-size:calc(12px * var(--reader-scale))}
.eyebrow:before{margin-bottom:5px}
.hero-copy,.section-heading p{font-size:calc(17px * var(--reader-scale));line-height:1.78}
.nav-link{font-size:calc(14px * var(--reader-scale));line-height:1.5;padding-top:15px;padding-bottom:15px}
.brand strong{font-size:calc(15px * var(--reader-scale))}.brand small,.sidebar-note small{font-size:calc(12px * var(--reader-scale));line-height:1.5}.sidebar-note strong{font-size:calc(13px * var(--reader-scale))}
.primary-button,.pill-button,.method-tab,.toggle,.choice-button,.choice-row button{font-size:calc(13px * var(--reader-scale));font-weight:700;letter-spacing:.01em;min-height:44px}
.panel h3,.challenge-main h3{line-height:1.38}
.mission{padding:15px 14px;min-height:68px}.mission strong{font-size:calc(14px * var(--reader-scale));line-height:1.45}.mission small{font-size:calc(12px * var(--reader-scale));line-height:1.55;margin-top:5px}
.legend,.method-note,.solution-readout,.visual-caption{font-size:calc(13px * var(--reader-scale));line-height:1.65}
.method-equation,.math-step,.equation-box b{font-family:var(--reader-font);font-size:calc(17px * var(--reader-scale));line-height:1.65}
.lesson-step{padding:15px;gap:14px}.lesson-step strong{font-size:calc(14px * var(--reader-scale));line-height:1.5}.lesson-step span{font-size:calc(13px * var(--reader-scale));line-height:1.72;margin-top:5px}
.challenge-main>p,.feedback{font-size:calc(14px * var(--reader-scale));line-height:1.72}.answer-area input{font-size:calc(16px * var(--reader-scale));min-height:50px}
.concept-strip p,.principle-row span{font-size:calc(13px * var(--reader-scale));line-height:1.7}.concept-strip h3,.principle-row b{font-size:calc(15px * var(--reader-scale))}
.range-control>span,.sandbox-predict b,.sandbox-predict span{font-size:calc(13px * var(--reader-scale));line-height:1.55}
button:focus-visible,a:focus-visible,input:focus-visible{outline:4px solid var(--gold);outline-offset:4px}
.topbar-actions{display:flex;align-items:center;gap:8px}
.reading-settings-button:before{content:'Aa';font-weight:800;margin-right:7px;color:var(--coral)}
.reading-overlay{position:fixed;inset:0;background:rgba(16,34,61,.36);opacity:0;pointer-events:none;transition:opacity .2s;z-index:39}.reading-overlay.open{opacity:1;pointer-events:auto}
.reading-panel{position:fixed;top:0;right:0;width:min(460px,94vw);height:100vh;background:var(--white);padding:30px;box-shadow:-20px 0 60px rgba(16,34,61,.22);transform:translateX(105%);transition:transform .25s;z-index:40;overflow-y:auto}.reading-panel.open{transform:none}.reading-panel-head{display:flex;align-items:flex-start;justify-content:space-between;gap:20px}.reading-panel h2{font-size:calc(30px * var(--reader-scale));line-height:1.25;margin:5px 0 0}.reading-panel>p{font-size:calc(15px * var(--reader-scale));color:var(--muted);margin:24px 0}.reading-panel fieldset{border:1px solid #cfd3cf;border-radius:15px;padding:18px;margin:0 0 20px}.reading-panel legend{font-size:calc(14px * var(--reader-scale));font-weight:800;padding:0 7px}.setting-choices{display:grid;grid-template-columns:repeat(3,1fr);gap:7px}.setting-choices button{border:1px solid #bdc5c2;background:#fff;border-radius:10px;padding:10px 7px;cursor:pointer;font-size:calc(12px * var(--reader-scale));min-height:48px}.setting-choices button[aria-pressed="true"]{background:var(--ink);color:#fff;border-color:var(--ink)}.setting-toggle{display:flex;align-items:flex-start;gap:13px;padding:17px 3px;border-bottom:1px solid #dde0dc;cursor:pointer}.setting-toggle input{width:22px;height:22px;accent-color:var(--coral);flex:0 0 auto;margin-top:3px}.setting-toggle strong,.setting-toggle small{display:block}.setting-toggle strong{font-size:calc(14px * var(--reader-scale))}.setting-toggle small{font-size:calc(12px * var(--reader-scale));color:var(--muted);margin-top:4px;line-height:1.6}.reset-reading{margin-top:24px}.reading-guide{display:none;position:fixed;left:0;right:0;top:45%;height:3.8rem;background:rgba(242,184,75,.17);border-top:2px solid rgba(189,128,13,.4);border-bottom:2px solid rgba(189,128,13,.4);pointer-events:none;z-index:38}.reading-guide.on{display:block}
html.reduce-motion *,html.reduce-motion *:before,html.reduce-motion *:after{scroll-behavior:auto!important;animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important}
@media(max-width:720px){.reading-settings-button{font-size:0;width:44px;padding:8px}.reading-settings-button:before{font-size:15px;margin:0}.topbar-actions{gap:5px}.reading-panel{padding:24px 20px}.setting-choices{grid-template-columns:1fr}.sidebar-note{display:none}}

/* One-problem-at-a-time vertical lesson flow */
.problem-flow-intro{max-width:1120px;margin:0 auto 32px;padding:20px 24px;border-left:5px solid var(--coral);background:#f3efe5;border-radius:0 16px 16px 0;display:grid;gap:4px}.problem-flow-intro strong{font-size:calc(16px * var(--reader-scale))}.problem-flow-intro span{color:var(--muted);font-size:calc(14px * var(--reader-scale))}
.teacher-intro{max-width:1120px;margin:0 auto 44px;background:var(--ink);color:#fff;border-radius:22px;padding:clamp(24px,4vw,38px);display:grid;grid-template-columns:minmax(0,1fr) minmax(300px,.85fr);gap:38px}.teacher-intro h3{font-size:calc(25px * var(--reader-scale));line-height:1.35;margin:7px 0 13px}.teacher-intro p{font-size:calc(14px * var(--reader-scale));color:#d3dbe6;line-height:1.75;margin:8px 0}.lesson-routine{list-style:none;margin:0;padding:0;display:grid;gap:10px}.lesson-routine li{background:rgba(255,255,255,.09);border-radius:12px;padding:12px 15px;display:grid;grid-template-columns:60px 1fr;gap:10px}.lesson-routine b{color:#ffb09f;font-size:calc(13px * var(--reader-scale))}.lesson-routine span{font-size:calc(12px * var(--reader-scale));line-height:1.6;color:#e5e9ee}
.problem-flow{max-width:1120px;margin:auto;display:grid;gap:56px}.problem-flow-card{background:#fff;border:1px solid #d7d8d3;border-radius:26px;padding:clamp(22px,4vw,42px);box-shadow:0 18px 50px rgba(16,34,61,.08);scroll-margin-top:95px;min-width:0}.problem-flow-card.complete{border-color:#8dcfbe;box-shadow:0 18px 50px rgba(34,123,104,.1)}
.problem-flow-head{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:18px;padding-bottom:25px;border-bottom:1px solid #dfe0db}.problem-flow-head h3{font-size:calc(25px * var(--reader-scale));line-height:1.32;margin:3px 0 0}.problem-number{min-width:62px;height:62px;border-radius:16px;background:var(--ink);color:#fff;display:grid;place-items:center;padding:0 10px;font-size:calc(14px * var(--reader-scale));font-weight:800}.problem-status{align-self:start;background:#f0f2ee;border-radius:999px;padding:8px 13px;font-size:calc(12px * var(--reader-scale));font-weight:700}.complete .problem-status{background:#e1f5ef;color:#176b59}
.equation-context{background:#fff6dc;border:2px solid #e8bd54;border-radius:16px;padding:18px 20px;margin:24px 0}.equation-pair{display:grid;gap:9px;margin-top:10px}.equation-pair>div{display:grid;grid-template-columns:18px 1fr;align-items:center;gap:10px}.equation-pair i{display:block;width:16px;height:5px;border-radius:4px;background:var(--swatch)}.equation-pair strong{font-family:var(--reader-font);font-size:calc(19px * var(--reader-scale));line-height:1.55;overflow-wrap:anywhere}
.teacher-guide{margin:0 0 28px;border:1px solid #cfdad6;border-radius:18px;overflow:hidden}.teacher-goal{padding:20px 22px;background:#e7f3ef;display:grid;gap:6px}.teacher-goal strong{font-size:calc(16px * var(--reader-scale));line-height:1.6}.teacher-explanation-grid{padding:0 22px}.teacher-explanation-grid>div{display:grid;grid-template-columns:minmax(145px,.28fr) minmax(0,1fr);gap:22px;padding:18px 0;border-top:1px solid #dfe5e2}.teacher-explanation-grid b{font-size:calc(14px * var(--reader-scale));color:#176b59}.teacher-explanation-grid p{font-size:calc(14px * var(--reader-scale));line-height:1.78;color:#465665;margin:0;max-width:72ch}
.problem-workspace{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(310px,.9fr);gap:28px;align-items:start}.problem-graph{min-width:0}.problem-graph canvas{display:block;width:100%;height:auto;background:#fbfaf5;border:1px solid #e0e1dc;border-radius:16px;margin-top:10px}.problem-practice{min-width:0}.problem-practice>.equation-context{margin-top:0;background:#fff9e8}.problem-practice>.equation-context .micro-label:after{content:' while answering'}
.problem-question{background:#f3f6f4;border-radius:18px;padding:22px}.problem-question h4{font-size:calc(21px * var(--reader-scale));line-height:1.42;margin:8px 0}.problem-question p{font-size:calc(14px * var(--reader-scale));color:#53606f;margin:0 0 18px}.problem-question .answer-area{display:grid;gap:8px}.problem-question .choice-button{text-align:left;background:#fff;color:var(--ink);border:2px solid #c7ceca}.problem-question .choice-button.selected{background:var(--ink);border-color:var(--ink);color:#fff}.problem-question .answer-area input{width:100%;min-width:0;border:2px solid #aeb8b3}.question-actions{display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin-top:18px}.problem-question .feedback{min-height:28px}.problem-question .feedback.correct{color:#176b59}.problem-question .feedback.incorrect{color:#a43122}.problem-question .feedback.hint{color:#795400}
.show-me-button{background:#fff4d5;border-color:#d49e28}.show-me-panel{margin-top:8px;background:#fff8e6;border:2px solid #e2b449;border-radius:15px;padding:20px}.show-me-panel ol{margin:13px 0 16px;padding-left:28px;display:grid;gap:10px}.show-me-panel li{padding-left:4px;font-size:calc(14px * var(--reader-scale));line-height:1.72;color:#394957}.show-me-panel li::marker{font-weight:800;color:#986600}.show-me-panel>strong{display:block;border-top:1px solid #e4cca0;padding-top:13px;font-size:calc(13px * var(--reader-scale));line-height:1.6;color:#674b13}
.mastered-message{background:#e7f7f2;border:2px solid #87cbb9;border-radius:18px;padding:24px;display:grid;gap:5px}.mastered-message strong{color:#176b59;font-size:calc(17px * var(--reader-scale))}.mastered-message span{font-size:calc(13px * var(--reader-scale));color:#385e55}
.worked-panel{margin-top:28px;background:#eef5f3;border-radius:18px;padding:24px}.worked-panel.locked{background:#f1f1ed;color:#656d74}.worked-panel h4{font-size:calc(20px * var(--reader-scale));line-height:1.4;margin:5px 0}.worked-panel p{font-size:calc(14px * var(--reader-scale))}.worked-steps{list-style:none;padding:0;margin:22px 0;display:grid;gap:10px}.worked-steps li{display:grid;grid-template-columns:34px 1fr;gap:12px;align-items:start;padding:13px;background:#fff;border-radius:12px;opacity:.32}.worked-steps li.visible{opacity:1}.worked-steps li>span{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;background:var(--ink);color:#fff;font-weight:800}.worked-steps li strong{font-size:calc(14px * var(--reader-scale));line-height:1.65}.flow-riddle{max-width:1120px;margin:56px auto 0;min-height:190px}
@media(max-width:900px){.teacher-intro,.problem-workspace{grid-template-columns:1fr}.problem-practice>.equation-context{position:static}.problem-flow{gap:38px}}
@media(max-width:560px){.problem-flow-head{grid-template-columns:auto 1fr}.problem-status{grid-column:1/-1;justify-self:start}.problem-number{min-width:52px;height:52px}.problem-flow-card{padding:20px 16px;border-radius:18px}.equation-context{padding:15px}.equation-pair strong{font-size:calc(16px * var(--reader-scale))}.teacher-explanation-grid>div{grid-template-columns:1fr;gap:5px}.problem-question{padding:18px 15px}.question-actions>*{width:100%}.lesson-routine li{grid-template-columns:1fr;gap:2px}}