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body{line-height:1.55}.sidebar{background:linear-gradient(165deg,#006d60,#004e54)}.nav-link{font-size:16px;min-height:48px;color:#d2ede8}.brand-caption,.nav-group-label,.sidebar-note{display:none}.sidebar .brand{margin:8px 0 28px}.topbar{padding:0 28px}.main-content{padding:28px;max-width:1680px}.breadcrumbs,.mode-switch button,.save-status{font-size:14px}.btn,.btn.small,.filter{font-size:15px;min-height:44px;padding:9px 15px}.icon-button{width:44px;height:44px}.avatar{width:36px;height:36px}.btn.primary{background:#007c66;border-color:#007c66}.btn.primary:hover{background:#00614f}.btn.soft{background:#d9f5e9}.eyebrow,.panel .eyebrow{font-size:12px;letter-spacing:1px}.page-title,.lab-heading h1{font-size:30px}.subtext,.lab-heading .subtext{font-size:16px}.back-link{font-size:14px}.hero{background:#ddf7ed;border-color:#b1dfce}.hero h1{color:#005d50}.hero p{font-size:18px;line-height:1.6}.hero-art{background:radial-gradient(ellipse,#ffffff,#ddf7ed00)}.hero-art .mini-tag{font-size:11px}.section-row h2{font-size:23px}.card-grid{gap:20px}.card-art{height:160px}.card-pill{font-size:12px;background:#fff}.card-body{padding:22px}.card-body h3{font-size:21px}.card-body p{font-size:16px;line-height:1.55;min-height:0}.card-footer{font-size:13px}.home-bottom p{font-size:16px}.footer-line{font-size:13px}.lab-layout{grid-template-columns:minmax(0,1fr) 300px;gap:22px}.lab-tools{padding-top:0}.studio{border-radius:16px;box-shadow:0 8px 30px #16404d08}.studio-bar{padding:14px 20px}.studio-label{font-size:13px}.live-badge{display:none}.canvas{background-color:#f9fcff;min-height:360px}.canvas-hint{font-size:14px;color:#294f58;background:#fffffff2;max-width:calc(100% - 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@media(max-width:740px){.main-content{padding:20px 14px 90px}.sidebar .brand{display:none}.nav-link{font-size:12px;padding:5px 4px;min-height:48px}.nav-link .icon{width:21px;height:21px}.hero-text{padding:25px}.hero p{font-size:17px}.hero h1{font-size:44px}.hero-actions{flex-wrap:wrap;gap:10px}.card-body{padding:18px}.card-body h3{font-size:21px}.card-grid{grid-template-columns:1fr}.card-art{height:145px}.filters{gap:4px}.filter{font-size:14px;padding:8px 10px}.section-row{flex-wrap:wrap;gap:14px}.home-bottom{flex-wrap:wrap}.lab-heading h1,.page-title{font-size:28px}.lab-tools{gap:8px}.btn,.btn.small{min-height:44px;font-size:14px;padding:8px 12px}.inspector{display:flex;flex-direction:column}.step-list{display:grid;gap:12px}.panel{padding:18px}.panel p,.step{font-size:16px}.canvas-hint{font-size:13px;left:8px;bottom:8px}.linked-reps{grid-template-columns:1fr;padding:18px}.control-panel{padding:18px}.point-editor{flex-wrap:wrap}.catalog-toolbar{display:grid;grid-template-columns:1fr 1fr}.search-box{grid-column:1/-1}.catalog-toolbar select{width:100%;font-size:15px;min-width:0}.catalog-toolbar .helper{grid-column:1/-1}.outcome-item{padding:17px 15px;border-left-width:4px}.outcome-item h3{font-size:17px}.outcome-item small{font-size:13px}.outcome-tag{font-size:13px}.list-meta span:last-child{display:none}.early-grid{grid-template-columns:repeat(4,1fr);gap:30px 10px;padding:28px 18px 40px}.early-cell{min-height:60px}.early-foot{display:none}.algebra-sides{grid-template-columns:1fr 22px 1fr;padding:20px 10px;gap:5px}.algebra-side{padding:8px;gap:6px}.algebra-tile{min-width:38px;height:38px;font-size:16px}.algebra-tile.variable{min-width:40px;height:76px}.direct-tray{padding:14px;gap:12px}.balance-tray{margin-inline:10px}.build-toolbar{gap:2px;padding:7px}.build-tool,.build-expanded .build-tool{min-width:47px;min-height:58px;font-size:11px;padding:6px 5px}.build-tool svg{width:22px;height:22px}.build-instruction,.build-expanded .build-instruction{font-size:13px;min-height:43px;padding:8px 10px}.material-tabs{gap:3px;padding:5px 7px}.material-tabs button{font-size:13px;min-height:39px;padding:8px 10px}.shelf-items{min-height:89px;padding:6px 8px;gap:6px}.shelf-items .shelf-piece{min-width:88px;min-height:76px;max-width:108px}.shelf-items .shelf-piece svg{width:43px;height:43px}.shelf-items .shelf-piece span{font-size:12px}.material-paint>span{font-size:12px}.material-paint{gap:9px}.paint-chip{width:27px;height:27px;min-width:27px}.build-expanded .build-context{height:139px;flex-basis:139px;padding:8px 10px}.build-options label,.build-expanded .build-options label{font-size:12px}.build-options{gap:10px}.build-context-actions .btn,.build-expanded .build-context-actions .btn{font-size:12px;min-height:38px}.build-operation-status{font-size:12px}.build-readout{grid-template-columns:1fr}.build-readout strong{font-size:15px}.build-context-actions{gap:7px}.construction-notice{font-size:15px}.construction-notice strong{display:none}.construction-notice a{margin:0}.dialog{padding:20px}.dialog h2{font-size:22px}}
@media(max-height:620px){.build-expanded .build-toolbar{flex-wrap:nowrap;overflow-x:auto}.build-expanded .build-tool{min-height:48px}.build-expanded .build-instruction{min-height:34px}.build-expanded .shelf-items{min-height:70px}.build-expanded .shelf-piece{min-height:58px}.build-expanded .shelf-piece svg{height:32px}.build-expanded .build-context{height:120px;flex-basis:120px}}
@media print{details.panel>summary{font-size:17px}.direct-tray,.balance-tray,.material-drawer,.build-toolbar,.build-context{display:none}.drag-token{display:none}.main-content{padding:0}.sidebar{display:none}}

.canvas-clean>.cell-palette{padding:16px 20px 0;display:flex;gap:12px;align-items:center;justify-content:center}.early-note{padding-top:20px}.early-grid{padding-top:24px}.copy-model{padding-bottom:4px}

.tile-choice svg{width:44px;height:44px}.saved-grid{gap:18px}@media(max-width:500px){.saved-grid{grid-template-columns:1fr}.saved-content h3{font-size:20px}}

.substitution{margin-bottom:14px}.substitution summary{cursor:pointer;font-size:16px;color:#006f5b;font-weight:600}.substitution .control-group{margin:16px 0}.substitution .math-equation{margin-top:12px}

@media(max-width:450px){.build-expanded .build-options{flex-wrap:wrap;overflow:visible;white-space:normal;gap:5px 12px}.build-expanded .build-context{height:155px;flex-basis:155px}.material-paint>span{display:none}.material-paint{gap:7px}.context-link{font-size:12px;padding:4px}.paint-divider{margin:0}.material-tabs{scrollbar-width:thin}.shelf-items{scrollbar-width:thin}}

/* One geometric mark, legible in both navigation layouts. */
.brand img{width:44px;height:44px;flex-shrink:0}.mobile-brand img{width:34px;height:34px;flex-shrink:0}.mobile-brand{gap:9px}