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#scene{inset:36px 15px 65px}.scene-panel.expanded .scene-top{top:18px;left:24px}.scene-panel.expanded .scene-bottom{left:24px;right:24px;bottom:15px}.scene-panel.expanded:after{display:none}.scene-panel.expanded:before{inset:10px;border:1px solid #8299a65c}.kbd-hint{font:9px 'JetBrains Mono',monospace;color:#8ba0ad}@media(min-width:1700px){body{padding-left:65px;padding-right:65px}.workbench{grid-template-columns:minmax(0,1fr) 360px;gap:42px;height:64vh;max-height:740px}.lesson-content{padding-top:27px}.lesson-description{font-size:14px}.objective{font-size:13px}.card-art{height:115px}.card-art>svg{height:72px;width:100px}.card-copy strong{font-size:12px}}@media(max-width:1180px){body{padding:22px 30px 28px}.top-navigation{gap:20px}.topbar{gap:13px}.wordmark{font-size:21px}.wordmark img{width:37px;height:37px}.wordmark .brand-lab{font-size:10px}.workbench{grid-template-columns:minmax(0,1fr) 305px;gap:24px;min-height:540px}.lesson-panel{padding-left:21px}.interaction-hint{font-size:7px}.view-controls{gap:4px;padding:4px 6px}.view-controls button{width:24px}.lesson-heading-main{gap:13px}h1{font-size:39px}.course-progress{min-width:95px;max-width:108px;margin-right:0}.heading-controls{gap:7px}.lesson-card{min-width:120px;flex-basis:calc((100% - 80px)/6)}}@media(max-width:960px){body{padding:20px 23px 25px}.top-navigation{gap:15px;font-size:10px}.topbar{gap:8px}.wordmark .brand-lab{font-size:9px;letter-spacing:.8px}.wordmark{gap:6px;font-size:20px}.wordmark img{margin-right:1px}.brand-slash{margin:0 2px}.top-actions #help-button{display:none}.workbench{grid-template-columns:minmax(0,1fr) 280px;gap:20px;min-height:515px}.lesson-panel{padding-left:18px}.lesson-heading{padding:30px 0 24px;gap:14px}.lesson-heading-main{gap:9px}.lesson-number{font-size:9px}.heading-dash{font-size:11px}h1{font-size:32px;letter-spacing:-1.4px}.course-progress{min-width:84px;max-width:95px}.course-progress strong{font-size:10px}.course-progress em{font-size:8px}.heading-controls>button{width:24px}.interaction-hint{display:none}.scene-bottom{justify-content:center}.panel-tabs{gap:24px}.panel-tabs button{font-size:10px}.lesson-description{font-size:12px}.lesson-content h2{font-size:22px}.objective{font-size:11px}.run-button{font-size:10px}.lesson-card{min-width:110px}.card-copy strong{font-size:10px}.card-art{height:94px}.card-art>svg{width:79px;height:57px}}
@media(max-width:760px){body{padding:16px 19px 29px;background-size:20px 20px}.shell:before{top:-7px;left:-9px;width:10px;height:10px}.shell:after{right:-8px;bottom:-12px}.topbar{height:55px;gap:10px}.topbar:after{top:57px}.wordmark{font-size:19px;gap:7px;letter-spacing:-.5px}.wordmark img{width:32px;height:32px;margin-right:0}.wordmark .brand-lab{font-size:8px;letter-spacing:.8px}.wordmark .brand-slash{margin:0 1px}.top-navigation{display:none}.top-actions{margin-left:auto;gap:2px}.top-actions #help-button{display:none}.mobile-menu{display:flex;width:38px;min-height:44px;padding:8px}.mobile-menu svg{width:19px;height:19px}.lesson-heading{padding:27px 0 21px;gap:8px;align-items:center}.lesson-heading-main{gap:9px;flex:1}.lesson-number{font-size:10px}.heading-dash{display:none}h1{font-size:30px;letter-spacing:-1.3px;line-height:1.22}.heading-controls{display:none}.workbench{display:flex;flex-direction:column;gap:25px;min-height:0;height:auto}.scene-panel{height:395px;min-width:0;width:100%;flex-shrink:0}.scene-panel:before{bottom:55px}.scene-panel:after{bottom:44px;left:-8px}.scene-top{top:10px;left:0}.scene-view-toggle{font-size:9px;gap:9px}.scene-view-toggle button{min-height:35px;padding:7px 3px}#scene{inset:27px -6px 54px}.scene-bottom{bottom:0;justify-content:center;gap:10px}.interaction-hint{display:none}.desktop-hint{display:none}.touch-hint{display:inline}.view-controls{padding:0 5px;gap:2px}.view-controls button{width:43px;height:43px}.view-controls svg{width:16px;height:16px}.view-controls>span{margin:0;width:1px;height:18px}.lesson-panel{border:0;padding:0;min-height:0}.lesson-panel:before{display:none}.panel-tabs{gap:33px;border-top:1px solid #6d889d60}.panel-tabs button{font-size:11px;min-height:47px;padding:14px 0}.lesson-content{padding:21px 2px 10px 0;max-height:none;overflow:visible}.lesson-content h2{font-size:24px;line-height:1.3}.lesson-description{font-size:13px;line-height:1.7}.overview-intro{font-size:24px;line-height:1.3}.objective{font-size:12px;margin:12px 0}.lesson-kicker{font-size:9px}.field-note{font-size:11px}.lesson-footer{padding:9px 1px 3px}.run-button{font-size:12px;min-height:48px;padding:14px 15px}.run-button kbd{display:none}.run-button:after{content:'↵';margin-left:auto;color:#f0bfa3;font-size:20px;line-height:1}.sim-status{font-size:9px}.lesson-shelf{margin-top:30px;padding-top:31px}.shelf-actions>button:first-child{font-size:10px;margin-right:0}.shelf-actions>button:first-child span{margin-left:8px}.shelf-arrow{display:none}.lesson-cards{gap:14px;padding-bottom:4px}.lesson-card{min-width:95px;flex-basis:95px}.card-art{height:92px}.card-art>svg{width:72px;height:56px}.card-copy{padding:0 2px 3px}.card-copy strong{font-size:10px;white-space:nowrap}.card-num{width:27px;height:27px;font-size:9px}.hover-tip{display:none!important}.inspector{left:6px;bottom:66px;max-width:calc(100% - 16px);width:285px;padding:18px}.inspector .close{width:34px;height:34px}.inspector h3{font-size:21px}.inspector p{font-size:11px}.inspector dl{font-size:10px}.inspector .tip{font-size:10px}.schematic-panel{inset:53px 0 62px;padding:16px}.schematic-panel h3{font-size:21px}.schematic-panel>p{font-size:11px}.circuit-line{grid-template-columns:1fr 25px 1.3fr;gap:8px;font-size:9px}.circuit-line small{font-size:10px}.pinout-table{font-size:12px}.pinout-table td:first-child{font-size:10px}.spec-row{font-size:12px}.code-actions button{min-height:36px;padding:7px}.code-actions>span{font-size:11px}pre{font-size:11px;max-width:100%}.code-note{font-size:11px}.details-block summary{min-height:44px;font-size:11px}.steps li{font-size:12px}.complete-button{min-height:44px;font-size:11px}.control-box label{font-size:13px}.control-box output{font-size:11px}input[type=range]{height:24px}.experiment-button{font-size:11px;min-height:47px}.serial-lines{font-size:10px}.serial header{font-size:9px}.serial header span{font-size:7px}dialog{padding:22px 18px;max-width:calc(100vw - 24px);max-height:90dvh}.dialog-top{padding-bottom:18px;margin-bottom:18px}.dialog-top h2{font-size:25px;letter-spacing:-.8px}.dialog-top>button{width:36px;height:36px}.dialog-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:15px}.dialog-grid .lesson-card{padding:8px 5px 14px;min-width:0;max-width:none}.dialog-grid .card-copy strong{white-space:normal;font-size:11px}.dialog-grid .card-art{height:98px}.part-card strong{font-size:16px}.part-card small{font-size:11px}.settings-row{gap:12px;font-size:12px}.settings-row small{font-size:10px}.settings-row button{font-size:9px;padding:10px}.modal-copy{font-size:12px}.scene-panel.expanded{inset:10px}.scene-panel.expanded #scene{inset:34px 0 69px}.scene-panel.expanded .scene-top{left:12px;top:14px}.scene-panel.expanded .scene-bottom{left:11px;right:11px;bottom:14px}.scene-panel.expanded .interaction-hint{display:none}}
@media(max-width:380px){body{padding:14px 14px 25px}.wordmark{font-size:18px;gap:6px}.wordmark .brand-lab{font-size:7px;letter-spacing:.6px}.wordmark img{width:29px;height:29px}h1{font-size:27px;letter-spacing:-1px}.lesson-number{font-size:9px}.lesson-heading-main{gap:8px}.scene-panel{height:365px}.view-controls{padding:0 3px;gap:0}.view-controls button{width:39px;height:43px}.view-controls svg{width:15px}.dialog-grid{gap:11px}.lesson-card{min-width:88px;flex-basis:88px}.card-copy strong{font-size:9px}.card-art>svg{width:65px;height:51px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
#lesson-position{font:10px 'JetBrains Mono',monospace;color:#7b92a1;white-space:nowrap}.heading-controls .course-progress{margin-right:16px}.board-facts{margin:20px 0 23px;counter-reset:fact}.board-facts p{position:relative;padding-left:30px;margin:0 0 15px;color:#637c8c;font-size:12px;line-height:1.7;counter-increment:fact}.board-facts p:before{content:counter(fact,decimal-leading-zero);position:absolute;left:0;top:0;font:9px/1.8 'JetBrains Mono',monospace;color:#8b9fab;border-bottom:1px solid #a3b3bb;padding:0 2px}.board-facts b{font-weight:600;color:#355c77}.code-preview{margin-top:24px}.code-preview .code-actions{margin-bottom:8px}.code-preview .code-actions>button{font:9px 'JetBrains Mono',monospace;min-height:25px;padding:5px 0 5px 8px;color:#8b735d}.code-preview pre{font-size:10px;line-height:1.8;padding:12px 0}.audio-toggle{justify-content:flex-start;min-height:40px;font:10px 'JetBrains Mono',monospace;text-decoration:underline;text-underline-offset:5px;padding:8px 0}.audio-toggle[aria-pressed=true]{color:#a66b45}.instructions summary{font-size:10px}@media(max-width:1180px){.heading-controls .course-progress{display:none}}@media(max-width:760px){.board-facts p{font-size:12px;padding-left:29px;margin-bottom:13px}.board-facts{margin:20px 0 23px}.code-preview{margin-top:21px}.code-preview pre{font-size:11px;line-height:1.9}.code-preview .code-actions>button{font-size:10px;min-height:34px}.audio-toggle{min-height:44px;font-size:11px}.instructions summary{font-size:11px}}
/* Course navigation stays above the experiment. */
.lesson-shelf{margin:14px 0 0;padding:0 0 12px;display:grid;grid-template-columns:minmax(0,1fr) 94px;gap:14px;align-items:center;border-bottom:1px solid #8299a65c;min-width:0;height:112px}.shelf-heading{position:static;grid-column:2;grid-row:1;align-self:center;min-width:0}.shelf-actions{display:flex;flex-wrap:wrap;justify-content:center;gap:4px}.shelf-actions>button:first-child{margin:0 0 5px;width:100%;font-size:10px;min-height:26px;white-space:nowrap}.shelf-actions>button:first-child span{margin-left:5px}.shelf-arrow{display:grid;width:34px;height:34px;border:1px solid #91a9b456}.shelf-arrow:hover{background:#efe9dc}.lesson-cards{grid-column:1;grid-row:1;gap:13px;padding:4px 10px 6px;min-width:0;height:99px;background-position:0 15px;scroll-padding-inline:10px;mask-image:linear-gradient(to right,transparent 0,#000 9px,#000 calc(100% - 12px),transparent 100%)}.lesson-cards>.lesson-card{flex:0 0 116px;min-width:116px;max-width:116px;min-height:86px}.lesson-cards .card-art{height:68px;padding-top:20px}.lesson-cards .card-art>svg{width:60px;height:45px;flex-shrink:0}.lesson-cards .card-num{width:22px;height:22px;font-size:8px}.lesson-cards .card-copy{padding:1px 3px 0}.lesson-cards .card-copy strong{font-size:12px;line-height:1.3;white-space:nowrap;color:#58758a}.lesson-cards .lesson-card.active .card-copy strong{color:var(--accent-dark);font-weight:600}.lesson-heading{padding:23px 0 24px}.heading-controls{display:flex;gap:5px}.heading-controls>button{min-width:40px;min-height:42px}.heading-controls #choose-lesson{display:flex;align-items:center;justify-content:center;gap:10px;width:auto;padding:0 12px;border:1px solid #819bac70;font-size:14px;white-space:nowrap;min-height:40px}#lesson-position{font-size:11px;color:#4f6d81}.heading-controls .course-progress{margin-right:17px}#choose-lesson:hover{background:#eeeade}.workbench{height:clamp(575px,65vh,760px);min-height:575px;grid-template-columns:minmax(0,1fr) 360px;gap:32px}.lesson-panel{display:grid;grid-template-rows:auto minmax(0,1fr) auto;min-height:0;padding-left:25px}.lesson-content{min-height:0;overflow-y:auto;overflow-x:hidden;flex:initial;padding:22px 13px 30px 0;scrollbar-gutter:stable;scrollbar-width:thin;scrollbar-color:#8aa0ae #dce3e440;overscroll-behavior:contain}.lesson-content::-webkit-scrollbar{width:7px}.lesson-content::-webkit-scrollbar-track{background:#dce3e440}.lesson-content::-webkit-scrollbar-thumb{background:#8aa0ae;border-radius:3px}.lesson-content:after{content:'';display:block;height:7px}.lesson-footer{position:relative;padding:15px 3px 5px 0;border-top:1px solid #819aaa66;background:var(--paper);z-index:1;min-height:65px}.lesson-description,.board-facts p,.objective,.field-note,.code-note,.steps li,.spec-row,.pinout-table,.lesson-learning p,.learning-section p,.learning-section li,.try-it p{font-size:13px;line-height:1.75;color:#526f82}.board-facts p{font-size:13px}.lesson-content h2{font-size:25px}.control-box label{font-size:13px}.control-box output{font-size:12px}.panel-tabs button{font-size:12px;min-height:45px}.code-preview pre,pre{font-size:12px;line-height:1.85}.code-preview .code-actions>button,.code-actions>span,.code-actions button{font-size:11px}.details-block summary,.instructions summary{font-size:12px;min-height:40px}.complete-button{font-size:11px;min-height:44px}.run-button{font-size:12px;min-height:47px}.lesson-content pre{max-width:100%;overflow:auto}.lesson-content .code-preview{min-width:0}.view-controls button{position:relative}.view-controls button[data-tooltip]:is(:hover,:focus-visible):after{content:attr(data-tooltip);position:absolute;bottom:calc(100% + 12px);left:50%;transform:translateX(-50%);background:var(--paper);border:1px solid #577b92;padding:7px 9px;color:#365a71;font:10px/1.4 'JetBrains Mono',monospace;white-space:nowrap;pointer-events:none;z-index:15}.view-controls button[data-tooltip]:last-child:is(:hover,:focus-visible):after{left:auto;right:0;transform:none}.view-controls button[data-tooltip]:first-child:is(:hover,:focus-visible):after{left:0;transform:none}.lesson-learning{margin-top:24px}.learning-section{padding-top:17px;margin-top:18px;border-top:1px solid #7e98aa55}.learning-section h3,.try-it h3{font:500 19px/1.35 'Space Grotesk',sans-serif;letter-spacing:-.35px;margin-bottom:10px;color:#345a73}.learning-section ul,.learning-section ol{margin:10px 0 0;padding-left:19px}.learning-section li+li{margin-top:8px}.learning-section code,.try-it code{font:11px 'JetBrains Mono',monospace;color:#aa6a48}.try-it{margin-top:20px;border-left:2px solid #bf805a88;padding:3px 0 3px 13px}.try-it h3{font-size:17px}.try-it p{margin:0}.try-it strong{color:#355b73}.lesson-learning>p+p,.learning-section p+p{margin-top:10px}#scene-action-hint{position:absolute;top:14px;right:8px;max-width:60%;font:10px/1.5 'JetBrains Mono',monospace;text-align:right;color:#8c6e55;pointer-events:none;z-index:3;background:#f8f5ebcc;padding:5px 8px}.scene-panel.expanded #scene-action-hint{top:21px;right:24px}.scene-top{z-index:4}.scene-panel:has(#scene-action-hint:not([hidden])) #scene{top:42px}
@media(min-width:1700px){.workbench{grid-template-columns:minmax(0,1fr) 395px;height:clamp(620px,66vh,790px);max-height:none}.lesson-cards>.lesson-card{flex-basis:135px;min-width:135px;max-width:135px}}
@media(max-width:1180px){.workbench{grid-template-columns:minmax(0,1fr) 335px;gap:23px;min-height:575px}.lesson-cards>.lesson-card{flex-basis:110px;min-width:110px;max-width:110px}.lesson-cards .card-copy strong{font-size:11px}.lesson-panel{padding-left:20px}.heading-controls .course-progress{display:none}}
@media(max-width:960px) and (min-width:761px){.lesson-heading{align-items:flex-start}.lesson-heading-main{padding-top:5px}h1{font-size:32px}.workbench{grid-template-columns:minmax(0,1fr) 315px;gap:18px;min-height:575px}.lesson-panel{padding-left:17px}.lesson-content{padding-right:9px}.heading-controls #choose-lesson{gap:5px;padding:0 7px}.heading-controls>button{min-width:32px}.lesson-shelf{grid-template-columns:minmax(0,1fr) 79px;gap:10px}.shelf-actions>button:first-child{font-size:9px}.shelf-arrow{width:31px;height:31px}}
@media(max-width:760px){.lesson-shelf{height:99px;margin-top:12px;padding-bottom:8px;grid-template-columns:minmax(0,1fr) 34px;gap:6px}.shelf-heading{align-self:center}.shelf-actions{gap:5px}.shelf-actions>button:first-child{display:none}.shelf-arrow{display:grid;width:32px;height:36px;border-color:#91a9b45e}.shelf-arrow svg{width:12px;height:12px}.lesson-cards{height:88px;padding:3px 9px 4px;gap:9px;background-position-y:13px;mask-image:linear-gradient(to right,transparent 0,#000 7px,#000 calc(100% - 10px),transparent 100%)}.lesson-cards>.lesson-card{flex-basis:106px;min-width:106px;max-width:106px;min-height:78px}.lesson-cards .card-art{height:59px;padding-top:17px}.lesson-cards .card-art>svg{height:39px;width:53px}.lesson-cards .card-num{width:20px;height:20px;font-size:8px}.lesson-cards .card-copy{padding:3px 1px 0}.lesson-cards .card-copy strong{font-size:11px;line-height:1.3}.lesson-heading{display:flex;flex-wrap:wrap;gap:13px;padding:22px 0 18px}.lesson-heading-main{flex-basis:100%;gap:10px;align-items:baseline}.lesson-heading h1{font-size:30px;line-height:1.2}.lesson-number{font-size:11px}.heading-controls{display:flex;gap:7px;align-items:center;width:100%;justify-content:space-between}.heading-controls .course-progress{display:none}.heading-controls>button{min-height:42px;min-width:44px;width:44px;border:1px solid #819bac55}.heading-controls #choose-lesson{flex:1;min-height:42px;min-width:0;max-width:none;gap:13px;font-size:15px;border-color:#819bac70}#lesson-position{font-size:12px}.workbench{display:flex;flex-direction:column;height:auto;min-height:0;gap:22px}.scene-panel{height:385px}#scene{inset:34px 0 55px}.scene-panel:has(#scene-action-hint:not([hidden])) #scene{top:51px}.lesson-panel{display:flex;flex-direction:column;padding:0;border:0;min-height:0}.panel-tabs{order:1}.lesson-content{order:3;overflow:visible;scrollbar-gutter:auto;padding:20px 0 15px;min-height:0;max-height:none;flex:initial}.lesson-footer{order:2;border-top:0;border-bottom:1px solid #819aaa44;padding:14px 3px 16px 0;background:none;min-height:0}.panel-tabs button{font-size:12px;min-height:47px}.lesson-description,.board-facts p,.objective,.field-note,.code-note,.steps li,.spec-row,.pinout-table,.lesson-learning p,.learning-section p,.learning-section li,.try-it p{font-size:13px;line-height:1.75}.lesson-content pre,.code-preview pre{font-size:12px;line-height:1.85}.code-preview .code-actions>button,.code-actions>span,.code-actions button{font-size:11px}.control-box label{font-size:13px}.control-box output{font-size:12px}.instructions summary,.details-block summary{font-size:12px;min-height:44px}.complete-button{font-size:11px}.run-button{min-height:48px;font-size:12px}.view-controls button[data-tooltip]:is(:hover,:focus-visible):after{display:none}#scene-action-hint{top:12px;right:0;max-width:64%;font-size:9px;line-height:1.5;padding:5px 0 5px 8px}.learning-section h3{font-size:19px}.try-it h3{font-size:18px}.scene-panel.expanded #scene-action-hint{top:13px;right:14px}.scene-panel.expanded #scene{inset:51px 0 69px}.lesson-shelf:before{display:none}}
@media(max-width:380px){.lesson-heading h1{font-size:27px}.lesson-heading{padding-top:20px}.lesson-cards>.lesson-card{flex-basis:101px;min-width:101px;max-width:101px}.scene-panel{height:365px}.lesson-cards .card-copy strong{font-size:10px}.heading-controls>button{min-height:42px;min-width:42px}.heading-controls #choose-lesson{min-height:42px}#scene-action-hint{max-width:61%;font-size:8px}}
/* Run is adjacent to the scene; learning and code retain their own scroll area. */
.lesson-panel{grid-template-rows:auto auto minmax(0,1fr)}.lesson-panel>.lesson-footer{grid-row:1;order:0;padding:0 3px 17px 0;border:0;background:none;min-height:0}.lesson-panel>.panel-tabs{grid-row:2;order:1;gap:0;justify-content:space-between}.lesson-panel>.panel-tabs button{flex:0 1 auto;padding-inline:0;min-width:0;font-size:11px}.lesson-panel>.lesson-content{grid-row:3;order:2}.lesson-learning h3{font:500 20px/1.35 'Space Grotesk',sans-serif;letter-spacing:-.35px;margin-bottom:11px;color:#345a73}.interaction-cue{color:#745b49;font-size:12px;line-height:1.7;margin:14px 0;padding-left:11px;border-left:2px solid #bd805a88}.interaction-cue b,.interaction-cue strong{font-weight:600;color:#73533e}#scene-action-hint.interaction-cue{margin:0;border:0}.learning-section:first-child{margin-top:0}.lesson-learning{margin-top:0}.lesson-learning ol,.lesson-learning ul{padding-left:20px}.lesson-learning li{font-size:13px;line-height:1.75;color:#526f82}.lesson-learning li+li{margin-top:8px}.lesson-learning code{font:11px 'JetBrains Mono',monospace;color:#aa6a48}.lesson-learning pre code{font:inherit;color:inherit}#open-learn{border-bottom:1px solid #aa785c;font:11px 'JetBrains Mono',monospace;padding:7px 0 5px;color:#9c694c;min-height:34px}#open-learn:hover{color:#75452e}.lesson-content>button#open-learn{margin:14px 0 4px}.lesson-learning .try-it p{font-size:13px;line-height:1.75}
@media(max-width:760px){.lesson-panel>.lesson-footer{order:0;padding:0 3px 18px 0;border:0;background:none}.lesson-panel>.panel-tabs{order:1;gap:0;justify-content:space-between}.lesson-panel>.panel-tabs button{font-size:12px;padding:14px 0;min-height:47px}.lesson-panel>.lesson-content{order:2;padding-top:20px}.lesson-learning h3{font-size:20px}.interaction-cue{font-size:12px}#open-learn{font-size:11px;min-height:42px}}
@media(max-width:380px){.lesson-panel>.panel-tabs button{font-size:11px}}
/* A fixed expanded workbench must release the mobile section's explicit size. */
.scene-panel.expanded{height:auto;width:auto;min-height:0}
.scene-panel.expanded #scene canvas{touch-action:none!important}
.piano-keys button.is-pressed{background:#dce4e5;transform:translateY(2px)}
.learning-section p+p{margin-top:12px}.takeaway{border-left:2px solid #bf805e;padding-left:14px;font-size:13px;line-height:1.8}
#scene{touch-action:pan-y}
.scene-panel.expanded #scene{touch-action:none}

/* Desktop is one viewport. Only the lesson and schematic reading areas scroll. */
@media (min-width:761px) {
  html { height:100%; overflow:hidden; }
  body {
    height:100dvh;
    min-height:0;
    overflow:hidden;
    padding:clamp(12px,1.8dvh,22px) clamp(24px,3vw,48px) 16px;
  }
  .shell {
    height:100%;
    min-height:0;
    display:flex;
    flex-direction:column;
  }
  .shell:after { bottom:-9px; }
  .topbar {
    height:clamp(48px,6.5dvh,68px);
    min-height:0;
    flex:0 0 auto;
  }
  .topbar:after { top:calc(100% + 1px); }
  .wordmark img { width:36px; height:36px; }
  .top-navigation>button,.top-actions>button { min-height:44px; }
  .shell>main {
    flex:1 1 0;
    min-width:0;
    min-height:0;
    display:grid;
    grid-template-rows:auto auto minmax(0,1fr);
  }
  .lesson-shelf {
    height:clamp(84px,10.8dvh,112px);
    min-height:0;
    margin-top:10px;
    padding:0 0 8px;
  }
  .lesson-cards {
    height:100%;
    min-height:0;
    padding:3px 10px 4px;
    align-items:stretch;
    overflow-y:hidden;
  }
  .lesson-cards>.lesson-card { min-height:0; }
  .lesson-cards .card-art {
    height:auto;
    flex:1 1 0;
    min-height:42px;
    padding-top:20px;
  }
  .lesson-cards .card-art>svg {
    height:clamp(29px,4.3dvh,45px);
    width:60px;
  }
  .lesson-cards .card-copy { flex:0 0 auto; padding:2px 3px 0; }
  .lesson-cards .card-copy strong { font-size:11px; line-height:1.4; }
  .lesson-heading {
    min-height:0;
    align-items:center;
    padding:clamp(12px,1.8dvh,20px) 0;
  }
  .lesson-heading h1 {
    font-size:clamp(25px,2.7vw,42px);
    line-height:1.12;
    letter-spacing:-1.2px;
  }
  .heading-controls { align-items:center; }
  .heading-controls>button,
  .heading-controls #choose-lesson { min-height:44px; }
  .workbench {
    height:100%;
    min-height:0;
    max-height:none;
    min-width:0;
    align-items:stretch;
  }
  .scene-panel:not(.expanded) { height:100%; min-height:0; }
  #scene { top:40px; bottom:48px; }
  .scene-top { top:5px; }
  .scene-view-toggle button { min-height:34px; }
  #scene-action-hint { top:6px; }
  .scene-bottom { min-height:46px; }
  .view-controls { padding:0 5px; }
  .view-controls button { width:40px; height:44px; }
  .interaction-hint { min-width:0; max-width:180px; line-height:1.6; }
  .lesson-panel {
    height:100%;
    min-height:0;
    display:grid;
    grid-template-rows:auto auto minmax(0,1fr);
  }
  .lesson-panel>.lesson-footer { padding:0 3px 12px 0; }
  .run-button { min-height:44px; }
  .lesson-panel>.panel-tabs button { min-height:44px; padding:11px 0; }
  .lesson-panel>.lesson-content {
    min-height:0;
    max-height:none;
    overflow:auto;
    overscroll-behavior:contain;
    padding-top:17px;
    padding-bottom:24px;
    scrollbar-gutter:stable;
  }
  .schematic-panel {
    inset:48px 0 60px;
    min-height:0;
    overflow:auto;
    overscroll-behavior:contain;
    scrollbar-width:thin;
    scrollbar-color:#8aa0ae #eee9dd;
  }
  .inspector { max-height:calc(100% - 104px); overflow:auto; }
}

/* Keep the same hierarchy on short laptop windows; retain full-size controls. */
@media (min-width:761px) and (max-height:700px) {
  body { padding-top:10px; padding-bottom:10px; }
  .shell:before { top:-6px; }
  .shell:after { bottom:-5px; }
  .topbar { height:44px; }
  .wordmark { font-size:21px; }
  .wordmark img { width:32px; height:32px; }
  .lesson-shelf { height:78px; margin-top:6px; padding-bottom:6px; }
  .lesson-cards { padding-top:2px; padding-bottom:2px; background-position-y:11px; }
  .lesson-cards .card-art { min-height:39px; padding-top:16px; }
  .lesson-cards .card-art>svg { height:30px; }
  .lesson-cards .card-num { width:19px; height:19px; font-size:8px; }
  .lesson-cards .card-copy { padding-top:1px; }
  .lesson-heading { padding:8px 0; }
  .lesson-heading h1 { font-size:clamp(24px,2.4vw,34px); }
  .lesson-panel>.lesson-footer { padding-bottom:8px; }
  .lesson-panel>.lesson-content { padding-top:13px; }
  .sim-status { margin-bottom:5px; }
}

/* Small, accessible links in the workbench header. */
.social-links { display:flex; align-items:center; gap:2px; }
.social-link {
  display:grid;
  place-items:center;
  width:38px;
  height:44px;
  flex:0 0 38px;
  color:#58758a;
  border-radius:3px;
}
.social-link svg { width:18px; height:18px; }
.social-link:hover { color:var(--accent-dark); background:#ece6d950; }
.social-link:focus-visible { outline:2px solid var(--accent-dark); outline-offset:1px; }
@media (max-width:359px) {
  .wordmark .brand-lab,.wordmark .brand-slash { display:none; }
}

/* Assembly entry and the Blink control-to-code connection. */
.top-navigation { gap:20px; }
#build-root { flex:1 1 0;min-width:0;min-height:0; }
.build-launch { display:flex;align-items:center;justify-content:space-between;width:100%;border:1px solid var(--line);padding:12px 14px;margin-top:12px;min-height:44px;font-size:12px;color:var(--accent-dark); }
.build-launch:hover { background:#c8754e0b; }
.control-constant { font:9px 'JetBrains Mono',monospace;color:var(--muted);margin-left:8px; }
.control-note { color:var(--muted);font-size:11px;line-height:1.5;margin:8px 0 0; }
@media (max-width:1100px) and (min-width:761px) { .top-navigation {gap:12px;font-size:10px;} .topbar {gap:16px;} }