:root{color-scheme:light;--plum:#240b21;--rose:#a15f74;--paper:#fffdfb;--soft:#f3edef;--line:#dfd2d9;--muted:#715b69;font-family:Arial,Helvetica,sans-serif;color:var(--plum);background:var(--paper)}*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit}a{color:inherit;text-underline-offset:4px}button{cursor:pointer;min-height:44px;border:1px solid var(--line);border-radius:24px;padding:10px 17px;color:var(--plum);background:var(--paper)}button:hover{border-color:var(--rose);background:var(--soft)}:focus-visible{outline:3px solid #7d365e;outline-offset:4px}header,footer{max-width:1320px;margin:auto;padding:26px 40px;display:flex;align-items:center;justify-content:space-between;gap:20px}header{border-bottom:1px solid var(--line)}header>a:last-child{font-size:13px}.brand{display:flex;gap:20px;align-items:baseline;text-decoration:none}.brand strong{font-size:27px;letter-spacing:-1.4px}.brand span{font-size:12px;color:var(--muted)}main{max-width:1320px;margin:auto;padding:0 40px}.intro{display:flex;justify-content:space-between;align-items:end;gap:30px;padding:54px 0 36px}.eyebrow{font-size:10px;letter-spacing:2px;font-weight:700;line-height:1.6;margin:0 0 16px}h1{font-size:clamp(42px,5.6vw,76px);line-height:1.02;letter-spacing:-3px;font-weight:500;margin:0}h1 em{font-family:Georgia,serif;font-weight:400;color:#82536a}p{line-height:1.6}.lede{color:var(--muted);max-width:360px;font-size:15px;margin-bottom:5px}.modes{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-bottom:22px}.modes button{border-radius:16px;text-align:left;padding:18px 22px;font-size:18px}.modes span{display:block;font-size:9px;letter-spacing:1.5px;margin-bottom:8px}.modes [aria-pressed=true]{background:var(--plum);color:var(--paper);border-color:var(--plum)}.workbench{display:grid;grid-template-columns:minmax(0,1.65fr) minmax(290px,1fr);border:1px solid 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.scope-note{display:flex;justify-content:space-between;gap:16px;font-size:12px;color:var(--muted);margin:0 0 18px}.catalogue{padding:35px 0;border-top:1px solid var(--line);scroll-margin-top:20px}.catalogue h2{font-size:38px}.catalogue-intro{max-width:740px;color:var(--muted)}.catalogue-controls{display:flex;gap:16px;flex-wrap:wrap;margin:24px 0}.catalogue-controls label{display:grid;gap:8px;font-size:12px;flex:1;min-width:210px}.catalogue-controls input,.catalogue-controls select{width:100%;min-height:48px;border:1px solid var(--line);border-radius:12px;background:white;padding:12px;font:inherit;color:var(--plum)}#catalogue-count{font-size:12px;color:var(--muted)}.family{border-top:1px solid var(--line)}.family:last-child{border-bottom:1px solid var(--line)}.family summary{cursor:pointer;display:flex;align-items:center;gap:18px;min-height:86px;padding:18px 6px}.family summary::before{content:'+';font-size:24px;flex:none;width:20px}.family[open] summary::before{content:'−'}.family-title{font-size:21px;letter-spacing:-.4px;margin-right:auto}.family-status{font-size:11px;border-radius:20px;background:var(--soft);padding:8px 12px}.family-number{font-size:11px;white-space:nowrap;color:var(--muted)}.family-body{padding:0 42px 26px;max-width:920px;font-size:14px;color:var(--muted)}.family-body h3{font-size:13px;color:var(--plum);margin:20px 0 4px}.family-body p{margin:6px 0 12px}.engine-names{font-size:12px;line-height:1.8}.roadmap{background:var(--soft);padding:25px 30px;border-radius:20px;margin-top:30px}.roadmap h3{font-weight:500;font-size:24px;margin:0 0 16px}.roadmap ol{padding-left:20px;line-height:1.6;font-size:14px}.roadmap li{margin:12px 0}@media(max-width:600px){.scope-note{flex-direction:column;gap:8px}.catalogue h2{font-size:31px}.family summary{flex-wrap:wrap;gap:10px}.family-title{width:calc(100% - 35px);font-size:19px}.family-status{margin-left:30px}.family-body{padding:0 15px 24px}.roadmap{padding:22px}.catalogue-controls{gap:12px}}

/* Study palette, read from current /study/kit.css. Scope stays within this route. */
:root{--plum:#222A55;--rose:#2A7D63;--paper:#FFFFFF;--soft:#F2EDE4;--line:#E8E1D5;--muted:#4A5070;background:#F7F3EC;font-family:'Instrument Sans',system-ui,sans-serif}body{background:#F7F3EC}header{background:white;border:1px solid var(--line);border-radius:22px;margin:16px auto 0;max-width:1240px;padding:18px 24px}.brand strong,h1,h2,h3,.family-title,.modes button{font-family:'Fredoka','Instrument Sans',sans-serif}.brand strong{letter-spacing:-.5px;font-weight:600}.intro{padding:34px;margin:24px 0;border:1px solid var(--line);border-radius:32px;background:white;align-items:center}.intro .eyebrow{letter-spacing:1.2px;color:#2A7D63}h1{font-size:clamp(40px,5vw,66px);font-weight:600;letter-spacing:-1.3px;line-height:1.05}h1 em{font:inherit;color:#222A55;background:linear-gradient(transparent 65%,#F7E7A6 65%,#F7E7A6 93%,transparent 93%)}.intro-side{display:flex;align-items:center;gap:18px;max-width:420px}.intro-side img{width:140px;height:140px;object-fit:contain}.lede{font-size:16px}.modes button{background:#fff;border:2px solid var(--line);font-weight:500;font-size:20px}.modes span{font-family:'Instrument Sans',sans-serif;font-size:11px;letter-spacing:1px}.modes [data-mode=symmetry][aria-pressed=true]{background:#BFDDF5;color:#222A55;border-color:#3A6FB8}.modes [data-mode=waves][aria-pressed=true]{background:#DCF2E8;color:#222A55;border-color:#2A7D63}.modes [data-mode=regions][aria-pressed=true]{background:#F7E7A6;color:#222A55;border-color:#947413}.visual{background:#F2EDE4}.visual-head>span{font-size:11px;letter-spacing:.5px}.visual-head button{background:#fff;font-size:13px}.workbench{box-shadow:0 14px 34px -22px rgba(27,36,82,.3)}.readout{background:#fff}.lesson{padding:30px}h2{font-weight:500;font-size:30px;letter-spacing:-.4px}.lesson>p:not(.eyebrow){font-size:15px}.control>span{font-size:15px}.control input{accent-color:#2A7D63;min-height:32px}.actions button{font-size:13px}.actions #deeper{background:#F7E7A6;border-color:#F7E7A6}.practice{background:#DCF2E8;color:#222A55;border:1px solid #b9dfce}.practice .eyebrow{color:#1E5E4A}.practice p{font-size:15px}.primary{background:#222A55;color:#fff;border-color:#222A55}.primary:hover{background:#3C4470;color:#fff}#feedback{color:#4A5070}#feedback[data-correct=true]{color:#1E5E4A}#mission{background:#FBF3D2;color:#222A55!important;border-left:4px solid #b79930;border-radius:8px;padding:14px;font-size:14px}.family-status{background:#DCF2E8;color:#1E5E4A}.family{background:white;padding:0 12px}.family:first-child{border-radius:20px 20px 0 0}.family:last-child{border-radius:0 0 20px 20px}.family summary{min-height:88px}.family-status,.family-number{font-size:12px}.roadmap{background:#FBF3D2}.scope-note{font-size:13px}.eyebrow{font-size:11px}footer{background:transparent}@media(max-width:800px){header{margin:12px 16px 0}.intro{padding:24px;gap:22px}.intro-side{max-width:100%}.intro-side img{width:95px;height:95px}.lede{font-size:14px}.modes button{font-size:16px;padding:14px 10px}.modes span{font-size:9px;letter-spacing:.2px}.visual-head>span{font-size:10px}.lesson{padding:24px}.brand span{max-width:130px}.practice{padding:24px}}
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/* Keep optional lessons usable under mobile text scaling and iOS form focus. */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}header,main,.intro,.intro-side,.workbench,.lesson,.visual,.practice,.export-sheet,.catalogue-controls>*{min-width:0}input,select,textarea{font-size:16px!important}.intro-side img{flex-shrink:0}canvas,img{max-width:100%}@media(max-width:480px){.intro-side{flex-wrap:wrap}.intro-side .lede{flex:1;min-width:140px}.modes{grid-template-columns:1fr}.modes button{text-align:left}.catalogue-controls label{min-width:0}.scope-note{overflow-wrap:anywhere}}