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var(--space-32)}.hero-copy{padding-top:var(--space-8)}.hero h1{font-size:var(--type-display-size);line-height:var(--type-display-line);font-weight:var(--type-display-weight);letter-spacing:var(--type-display-tracking)}.hero-copy .lead{margin-top:var(--space-24);max-width:48ch}.hero-actions{display:flex;align-items:center;gap:var(--space-24);flex-wrap:wrap;margin-top:var(--space-32)}.hero-task{background:var(--color-surface);border:1px solid var(--color-divider);border-radius:var(--radius-panel);padding:var(--space-32)}.hero-task-heading{display:flex;align-items:baseline;justify-content:space-between;gap:var(--space-16);margin-bottom:var(--space-20)}.hero-task-heading h2{font-size:24px;line-height:32px;font-weight:600;letter-spacing:-.02em}.hero-task-heading 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ol{padding-left:var(--space-24);margin-block:var(--space-20)}.prose li+li{margin-top:var(--space-12)}.prose strong{font-weight:600}.prose .table-wrap{margin-block:var(--space-24)}.prose table{width:100%;border-collapse:collapse;font-size:16px;line-height:26px;table-layout:fixed}.prose th,.prose td{padding:var(--space-16);border-bottom:1px solid var(--color-divider);text-align:left;vertical-align:top;overflow-wrap:anywhere}.prose th{background:var(--color-subtle);font-weight:600}.prose caption{text-align:left;margin-bottom:var(--space-16);font-weight:600}.prose img{display:block;margin-block:var(--space-24)}.collection-guide{padding-bottom:var(--space-24)}.collection-guide h2:first-child{margin-top:0}.next-material{padding-top:var(--space-16);border-top:1px solid var(--color-divider)}.next-material 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a{font-size:16px;line-height:24px;min-height:48px;padding:var(--space-12);text-decoration:none;border-radius:var(--radius-control)}.admin-nav [aria-current]{background:var(--color-selection)}.sample-form{max-width:720px;display:grid;gap:var(--space-24)}.field{display:grid;gap:var(--space-8);font-size:16px;line-height:24px}.field label{font-weight:600}.field input,.field textarea,.field select{min-width:0;width:100%;min-height:48px;padding:var(--space-12) var(--space-16);border:1px solid var(--color-border);border-radius:var(--radius-control);background:var(--color-surface);color:var(--color-text)}.field textarea{min-height:144px;resize:vertical}.field [readonly]{background:var(--color-subtle)}.field [aria-invalid=true]{border-color:var(--color-error)}.check-field{display:flex;gap:var(--space-12);align-items:center;min-height:44px;font-size:16px;line-height:24px}.check-field 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.button{justify-self:start}.role-display{font-size:var(--type-display-size);line-height:var(--type-display-line);font-weight:650;letter-spacing:-.035em}.role-page-title{font-size:var(--type-page-title-size);line-height:var(--type-page-title-line);font-weight:650;letter-spacing:-.03em}.role-section{font-size:var(--type-section-size);line-height:var(--type-section-line);font-weight:650;letter-spacing:-.025em}.role-item-title{font-size:var(--type-item-title-size);line-height:var(--type-item-title-line);font-weight:600;letter-spacing:-.02em}.role-lead{font-size:var(--type-lead-size);line-height:var(--type-lead-line);color:var(--color-secondary)}.role-prompt{font-size:var(--type-prompt-size);line-height:var(--type-prompt-line);font-weight:500}.role-label,.role-action{font-size:16px;line-height:24px;font-weight:600}.role-help{font-size:16px;line-height:26px;color:var(--color-secondary)}.role-meta{font-size:14px;line-height:22px;color:var(--color-secondary)}.role-grade{font-size:var(--type-grade-size);line-height:var(--type-grade-line);font-weight:600;letter-spacing:-.03em}.role-wordmark{font-size:var(--type-wordmark-size);line-height:var(--type-wordmark-line);font-weight:700;letter-spacing:-.035em}
@media(min-width:761px){.mobile-nav{display:none!important}}
@media(max-width:1100px) and (min-width:761px){.hero{gap:var(--space-32)}.hero h1{font-size:48px;line-height:56px}.hero-task{padding:var(--space-24)}.desktop-nav{gap:var(--space-20);margin-right:0}.header-inner{gap:var(--space-20)}.header-cta{padding-inline:var(--space-16)}.reading-layout{gap:var(--space-40)}.parent-section,.app-section-inner{gap:var(--space-40)}.grade-link{gap:var(--space-8);padding-inline:var(--space-8)}}
@media(max-width:760px){html{scroll-padding-top:var(--space-16)}.container{width:calc(100% - var(--layout-mobile-gutter)*2)}.header-inner{height:76px;gap:var(--space-16)}.brand-mark{width:24px;height:24px}.desktop-nav,.header-cta{display:none}.menu-toggle{display:grid;place-items:center}.hero{grid-template-columns:1fr;gap:var(--space-32);padding-block:var(--space-40) var(--space-16)}.hero-copy{padding:0}.hero-copy .lead{margin-top:var(--space-20)}.hero-actions{margin-top:var(--space-24);gap:var(--space-12) var(--space-20)}.hero-task{padding:var(--space-20)}.hero-task-heading{gap:var(--space-12);flex-wrap:wrap;margin-bottom:var(--space-16)}.hero-task-heading h2{font-size:22px;line-height:30px}.mat{min-height:88px}.mat-answer{font-size:14px;line-height:22px}.mats{gap:var(--space-8);margin-block:var(--space-20)}.section{margin-block:var(--space-48)}.section-heading{display:block;margin-bottom:var(--space-24)}.section-heading .help{margin-top:var(--space-12)}.section-heading .text-link{margin-top:var(--space-8)}.grade-list{grid-template-columns:repeat(3,minmax(0,1fr));gap:var(--space-12)}.grade-link{position:relative;min-height:96px;gap:var(--space-8);padding:var(--space-12) var(--space-8)}.grade-link .icon{display:none}.grade-label{font-size:16px}.topic-grid{grid-template-columns:1fr;gap:var(--space-16)}.topic-panel{padding:var(--space-24)}.pattern-example{gap:var(--space-20);font-size:32px;line-height:40px}.rebus-example{font-size:32px;line-height:40px}.topic-panel h3{margin-top:var(--space-24)}.topic-panel p{font-size:16px;line-height:26px}.parent-section{grid-template-columns:1fr;gap:var(--space-24)}.parent-section h2 br{display:none}.material-title{font-size:22px;line-height:30px}.material-row{padding-block:var(--space-20);gap:var(--space-16)}.app-section{padding-block:var(--space-40)}.app-section-inner{grid-template-columns:1fr;gap:var(--space-24)}.app-section h2{font-size:34px;line-height:42px}.site-footer{padding-top:var(--space-32)}.footer-main{display:block;padding-bottom:var(--space-24)}.footer-main nav{gap:var(--space-24);margin-top:var(--space-24)}.footer-bottom{display:grid;gap:var(--space-8)}.breadcrumbs{margin-top:var(--space-20)}.breadcrumbs li:last-child:not(:first-child){display:none}.page-intro{margin-top:var(--space-24);margin-bottom:var(--space-32)}.page-intro .lead{margin-top:var(--space-20)}.reading-layout{display:flex;flex-direction:column;gap:var(--space-32);margin-top:var(--space-32);margin-bottom:var(--space-48)}.toc{order:-1;position:static;width:100%}.toc summary{cursor:pointer}.toc summary .icon{display:block}.toc details:not([open]) nav{display:none}.toc details[open] nav{display:grid}.toc nav a{padding-block:var(--space-12)}.collection-body,.article-body{min-width:0;width:100%}.collection-guide{padding-bottom:var(--space-16)}.task{padding-block:var(--space-32)}.task-heading{gap:var(--space-12)}.task-heading h2{font-size:22px;line-height:30px}.task-prompt{margin-top:var(--space-20)}.task .disclosure{font-size:18px;line-height:30px}.prose h2{font-size:var(--type-prose-section-size);line-height:var(--type-prose-section-line);margin-top:var(--space-40)}.prose h3{font-size:22px;line-height:30px}.prose th,.prose td{padding:var(--space-12) var(--space-8)}.prose table{font-size:16px;line-height:26px}.catalog-row{align-items:start;gap:var(--space-16);flex-wrap:wrap}.catalog-grade{min-width:80px;font-size:32px;line-height:40px}.catalog-description{min-width:calc(100% - 112px)}.catalog-count{margin-left:96px;min-height:44px}.catalog-list{margin-top:var(--space-32)}.admin-layout{grid-template-columns:1fr;gap:var(--space-24)}.admin-nav{flex-direction:row;flex-wrap:wrap}.role-samples>p{max-width:100%}.swatches{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:360px){.container{width:calc(100% - var(--space-16)*2)}.hero-task{padding:var(--space-16)}.hero-task-heading h2{font-size:22px;line-height:30px}.pattern-example{gap:var(--space-16)}.grade-list{gap:var(--space-8)}.grade-link{gap:var(--space-4)}.hero-actions .button{width:100%}.mat-answer{font-size:14px}.mats{gap:var(--space-4)}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}
/* Quantity diagram: geometry recorded in design/styleguide.md. */
.quantity-diagram{margin:var(--space-32) 0;padding-block:var(--space-24);border-top:1px solid var(--color-divider);border-bottom:1px solid var(--color-divider)}.quantity-row{display:flex;align-items:center;gap:var(--space-24);margin-bottom:var(--space-16)}.quantity-row>span{display:flex;justify-content:space-between;gap:var(--space-16);min-width:96px;font-size:16px;line-height:24px}.quantity-cells{display:grid;grid-template-columns:repeat(9,24px);gap:var(--space-8)}.quantity-cell{width:24px;height:24px;background:var(--color-primary);border-radius:var(--space-4)}.quantity-missing{background:transparent;border:1px dashed var(--color-border)}.quantity-diagram figcaption{font-size:16px;line-height:26px;color:var(--color-secondary);margin-top:var(--space-20)}
@media(max-width:760px){.mat-answer{font-size:16px;line-height:24px}.quantity-row{flex-direction:column;align-items:start;gap:var(--space-8)}.quantity-row>span{min-width:80px}.quantity-cells{grid-template-columns:repeat(9,20px);gap:var(--space-4)}.quantity-cell{width:20px;height:20px}}
.field-error{font-size:16px;line-height:26px;color:var(--color-error)}.role-prose-section{font-size:var(--type-prose-section-size);line-height:var(--type-prose-section-line);font-weight:650;letter-spacing:-.025em}.role-prose-subsection{font-size:var(--type-prose-subsection-size);line-height:var(--type-prose-subsection-line);font-weight:600;letter-spacing:-.02em}
.task-prompt.prose{font-size:var(--type-prompt-size);line-height:var(--type-prompt-line);font-weight:var(--type-prompt-weight);letter-spacing:var(--type-prompt-tracking)}.task-prompt.prose>p:last-child{margin-bottom:0}.desktop-nav a,.footer-main nav a{font-weight:var(--type-navigation-weight)}.role-navigation{font-size:var(--type-navigation-size);line-height:var(--type-navigation-line);font-weight:var(--type-navigation-weight)}
/* Learning objects: real task data, not decorative marketing cards. */
.task-game{margin-block:var(--space-24);font-size:16px;line-height:26px}.game-fieldset{border:0;margin:0;padding:0;min-width:0}.game-fieldset legend{font-size:16px;line-height:24px;font-weight:600;margin-bottom:var(--space-16);padding:0}.shape-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,128px),1fr));gap:var(--space-12)}.shape-card{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:space-between;gap:var(--space-12);min-width:0;min-height:196px;padding:var(--space-12) var(--space-8) var(--space-16);border:1px solid var(--color-border);border-radius:var(--radius-game-card);background:var(--color-puzzle-paper);cursor:pointer;transition:transform var(--motion-game-duration) var(--motion-ease),box-shadow var(--motion-game-duration) var(--motion-ease),background var(--motion-game-duration) var(--motion-ease)}.shape-card input{position:absolute;opacity:0;width:1px;height:1px;left:50%;top:50%;margin:0}.shape-card-top{display:flex;align-items:center;justify-content:space-between;width:100%;padding-inline:var(--space-4);font-size:16px;line-height:24px;font-weight:600}.choice-dot{width:16px;height:16px;border:1px solid var(--color-border);border-radius:50%;background:var(--color-surface)}.shape-card[data-selected=true]{background:var(--color-puzzle-blue-surface);border-color:var(--color-puzzle-blue);outline:1px solid var(--color-puzzle-blue)}.shape-card[data-selected=true] .choice-dot{border:4px solid var(--color-puzzle-blue);background:var(--color-surface)}.shape-card:focus-within{outline:2px solid var(--color-focus);outline-offset:4px}.game-shape{width:72px;height:72px;overflow:visible}.shape-blue{fill:var(--color-puzzle-blue)}.shape-red{fill:var(--color-puzzle-red)}.shape-card-caption{font-size:16px;line-height:24px;text-align:center}.game-envelope{display:flex;align-items:center;gap:var(--space-16);padding:var(--space-20);margin-top:var(--space-20);background:var(--color-puzzle-blue-surface);color:var(--color-puzzle-blue);border-radius:var(--radius-control)}.game-envelope>svg{width:40px;height:36px}.game-envelope strong,.game-envelope [data-game-summary]{display:block;font-size:16px;line-height:26px}.game-envelope strong{font-weight:600}.game-envelope [data-game-summary]{margin-top:var(--space-4)}.game-actions{display:flex;align-items:center;gap:var(--space-16);flex-wrap:wrap;margin-top:var(--space-20)}.game-feedback:empty{display:none}.game-feedback{margin-top:var(--space-16);padding:var(--space-16) var(--space-20);border-radius:var(--radius-control);font-size:16px;line-height:26px;background:var(--color-subtle);color:var(--color-secondary)}.game-feedback[data-kind=notice]{background:var(--color-notice-surface);color:var(--color-notice)}.game-feedback[data-kind=incorrect]{background:var(--color-error-surface);color:var(--color-error)}.game-feedback[data-kind=correct]{background:var(--color-success-surface);color:var(--color-success)}.has-attribute-game .task-prompt .table-wrap{display:none}.game-instruction{font-size:16px;line-height:26px;color:var(--color-secondary);margin-bottom:var(--space-16)}.pet-bank{display:flex;flex-wrap:wrap;gap:var(--space-8);margin-bottom:var(--space-16)}.pet-choice{min-height:44px;border:1px solid var(--color-border);border-radius:var(--radius-control);padding:var(--space-8) var(--space-12);font-size:16px;line-height:24px;font-weight:600;background:var(--color-surface);color:var(--color-text)}.pet-choice[aria-pressed=true]{background:var(--color-primary);border-color:var(--color-primary);color:var(--color-on-primary)}.pet-choice[data-placed=true]:not([aria-pressed=true]){background:var(--color-selection);border-color:var(--color-primary);color:var(--color-primary)}.pet-mats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:var(--space-12)}.pet-slot{min-width:0;min-height:128px;display:flex;flex-direction:column;align-items:center;justify-content:space-between;gap:var(--space-8);border:1px dashed var(--color-border);border-radius:var(--radius-game-card);background:var(--color-subtle);color:var(--color-text);padding:var(--space-12) var(--space-8)}.pet-slot-number{font-size:14px;line-height:22px;color:var(--color-secondary)}.pet-slot-name{font-size:16px;line-height:24px;font-weight:600}.pet-slot-action{font-size:16px;line-height:24px;color:var(--color-secondary)}.pet-slot[data-filled=true]{background:var(--color-selection);border-style:solid;border-color:var(--color-primary)}.task-game[data-picked=true] .pet-slot{border-color:var(--color-primary);border-style:solid}.pet-slot:hover{border-color:var(--color-primary);background:var(--color-selection)}.hero-task .task-game{margin-top:var(--space-20);margin-bottom:var(--space-24)}
@media(hover:hover) and (prefers-reduced-motion:no-preference){.shape-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-game-lift)}}
@media(max-width:760px){.shape-cards{grid-template-columns:repeat(auto-fit,minmax(min(100%,128px),1fr))}.shape-card{min-height:196px;padding-inline:var(--space-8)}.pet-mats{gap:var(--space-8)}.pet-slot{padding:var(--space-12) var(--space-4);min-height:120px}.pet-slot-action{display:none}.game-actions{gap:var(--space-8) var(--space-12)}}
@media(max-width:360px){.shape-cards{grid-template-columns:repeat(2,minmax(0,1fr))}.game-envelope{padding:var(--space-16)}.pet-slot-action{display:none}.pet-slot{min-height:104px}.pet-choice{padding-inline:var(--space-8)}}
@media(prefers-reduced-motion:reduce){.shape-card{transition:none!important;transform:none!important}}
@media(max-width:360px){.pet-mats{gap:var(--space-4)}.pet-slot{padding-inline:0}}
.prereq-interactive{display:none}.has-attribute-game .prereq-original{display:none}.has-attribute-game .prereq-interactive{display:inline}
/* Shared cartoon character and direct manipulation components. */
.pet-bank{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:var(--space-8)}
.pet-choice{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-8);padding:var(--space-12) var(--space-4);cursor:grab;touch-action:none}
.pet-choice[aria-pressed=true]{background:var(--color-selection);color:var(--color-primary)}
.pet-art{display:block;width:var(--layout-pet-art);height:var(--layout-pet-art);object-fit:contain;pointer-events:none;user-select:none}
.pet-art[hidden]{display:none}.pet-slot{min-height:var(--layout-pet-mat);cursor:grab;touch-action:pan-y}
.pet-slot[data-filled=true]{touch-action:none}.pet-slot[data-filled=false]{justify-content:center}
.pet-slot[data-drop-target=true]{background:var(--color-selection);outline:2px solid var(--color-primary);outline-offset:2px;border-style:solid}
[data-drag-source=true]>.pet-art{opacity:.25}.pet-drag-ghost{position:fixed;z-index:1000;pointer-events:none;object-fit:contain;width:var(--layout-pet-ghost);height:var(--layout-pet-ghost);filter:drop-shadow(var(--shadow-pet-drag));transform:scale(1.06);user-select:none}
.task-game[data-dragging=true] .pet-choice,.task-game[data-dragging=true] .pet-slot{cursor:grabbing}
@media(max-width:760px){.pet-art{width:var(--layout-pet-art-mobile);height:var(--layout-pet-art-mobile)}.pet-slot{min-height:var(--layout-pet-mat-mobile)}}
@media(prefers-reduced-motion:reduce){.pet-drag-ghost{transform:none}}
.pet-choice[data-placed=true]:not([aria-pressed=true]) .pet-art{opacity:.25}
/* Fixed illustrated scene: empty and occupied use identical tracks. */
.pet-slot{display:grid;grid-template-rows:22px minmax(0,1fr);gap:var(--space-4);align-items:center;justify-items:center;justify-content:normal;height:var(--layout-pet-mat);min-height:0;padding:var(--space-8);border:1px solid transparent;background:transparent;isolation:isolate}
.pet-slot[data-filled=true],.pet-slot:hover,.task-game[data-picked=true] .pet-slot{background:transparent;border-color:transparent}
.pet-slot[data-filled=false]{justify-content:normal}.pet-stage{position:relative;display:block;width:100%;height:100%;min-height:0;pointer-events:none}
.rug-art{position:absolute;bottom:0;left:50%;transform:translateX(-50%);width:100%;max-width:160px;height:var(--layout-rug-art);object-fit:contain;pointer-events:none;user-select:none}
.pet-slot-art{position:absolute;bottom:var(--space-20);left:50%;margin-left:calc(var(--layout-pet-art) / -2);z-index:1}
.pet-slot[data-filled=false] .pet-slot-name{visibility:hidden}.pet-slot-name{align-self:center;white-space:nowrap}.pet-slot-action{align-self:center;font-size:16px;line-height:24px}
.pet-choice .pet-art{transition:transform var(--motion-game-duration) var(--motion-ease)}.pet-choice[aria-pressed=true] .pet-art{transform:translateY(-6px)}
.pet-slot[data-drop-target=true]{background:var(--color-selection);border-color:transparent;outline:2px solid var(--color-primary);outline-offset:0}
.task-game[data-picked=true] .pet-slot .rug-art,.pet-slot:hover .rug-art{filter:drop-shadow(var(--shadow-game-lift))}
.pet-drag-ghost{transform:none}
.pet-slot[data-drag-source=true] .pet-art{opacity:.25}
@media(max-width:760px){.pet-slot{height:var(--layout-pet-mat-mobile);min-height:0}.rug-art{height:var(--layout-rug-art-mobile)}.pet-slot-art{margin-left:calc(var(--layout-pet-art-mobile) / -2)}}
@media(max-width:360px){.pet-slot{padding-inline:0}}
@media(prefers-reduced-motion:reduce){.pet-choice .pet-art{transition:none}.pet-choice[aria-pressed=true] .pet-art{transform:none}}
/* Current navigation location: persistent, distinct from hover and focus. */
.toc nav a{padding-inline:var(--space-12);border-radius:var(--radius-control);font-size:var(--type-navigation-size);line-height:var(--type-navigation-line)}
.toc nav a[aria-current="location"]{background:var(--color-selection);color:var(--color-primary);font-weight:600;text-decoration:none}
.desktop-nav a[aria-current],.footer-main nav a[aria-current]{color:var(--color-primary);font-weight:600;text-decoration:underline}
.mobile-nav a[aria-current]{background:var(--color-selection);color:var(--color-primary);text-decoration:none}
.pet-landing-cue{position:absolute;width:24px;height:24px;left:50%;bottom:var(--space-32);transform:translateX(-50%);color:var(--color-primary);z-index:1}
.pet-slot[data-filled=true] .pet-landing-cue{display:none}
.shape-card{min-height:144px}
.game-envelope [data-game-summary]{display:flex;flex-wrap:wrap;align-items:center;gap:var(--space-12);min-height:36px;margin:0}
.game-envelope [data-game-summary] .game-shape{width:32px;height:32px}