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@media(max-width:560px){.header-inner{padding:0 16px;gap:12px}.brand{font-size:22px}.header-inner nav{gap:12px}.header-inner nav a{font-size:12px}.page-width{padding:0 16px}.home-intro h1{font-size:32px}.home-intro p{font-size:15px;max-width:285px;margin:auto}.course-grid{grid-template-columns:1fr}.course-card{padding:26px}.course-card h2{font-size:38px}.course-card>p:not(.course-meta){font-size:15px}.scratch-art{min-height:230px;flex-direction:row;gap:16px}.coming-art{order:0;border:1px dashed #dbcfc6;flex:1;min-height:140px;flex-direction:column;margin:0}.coming-art .icon{width:32px;height:32px}.block-stack{min-width:150px}.scratch-block{min-width:140px;font-size:12px;padding:9px 10px}.scratch-block span{padding:3px 9px}.board-art{height:220px;margin:16px 0}.start-course{font-size:16px}.course-meta{font-size:12px}.learning-path{display:grid;grid-template-columns:1fr 1fr;gap:22px;padding:28px 16px}.learning-path li{font-size:13px}.learning-path li:after{display:none}.site-footer{font-size:12px;padding:18px 12px}.classroom-shell{padding:0 16px}.overview-intro img{display:none}.overview-intro h1{font-size:34px}.course-info{font-size:12px}.course-info a{margin-left:0}.course-note{padding:16px;font-size:13px}.unit{padding-top:20px}.unit-heading h2{font-size:18px}.unit-lessons a{font-size:13px;gap:8px}.unit-lessons small{display:none}.unit-lessons .icon{margin-left:auto}.lesson-heading h1{font-size:28px;letter-spacing:-1px}.lesson-summary{font-size:15px}.section-nav{gap:0}.section-nav button{font-size:12px;padding:10px}.section-nav #print-lesson{display:none}.lesson-section{padding:22px 0}.lesson-section h2{font-size:20px}.goals,.theory,.steps,.result>p{font-size:14px}.materials{font-size:13px}.has-wiring{grid-template-columns:1fr}.code-title>span{font-size:10px}.code-toolbar{flex-wrap:wrap;padding:12px}.code-toolbar>div{width:100%;justify-content:flex-end}.code-toolbar>span{font-size:12px}pre{font-size:12px;padding:16px;max-height:450px}.challenge{padding:20px}.challenge>p{font-size:14px}.lesson-pagination{gap:10px}.lesson-pagination a{padding:10px 12px;max-width:49%}.lesson-pagination strong{font-size:12px}.lesson-pagination small{font-size:10px}.preparing{padding:26px 20px}.preparing h2{font-size:21px}.preparing p{font-size:14px}.scratch-heading h1{font-size:33px}.scratch-heading p{font-size:16px}dialog{padding:14px}.zoom-scroll{max-height:68vh}.toast{font-size:12px;width:max-content}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
@media print{.site-header,.site-footer,.sidebar,.section-nav,.code-toolbar>div,.code-title>span,.lesson-pagination,.toast,.figure-zoom>span,.skip-link{display:none!important}.classroom-shell{display:block;padding:0}.reading{padding:0}.lesson-heading h1{font-size:26px}.lesson-section{break-inside:auto}h2,h3{break-after:avoid}.code-panel{border:1px solid #ccc}pre{max-height:none;overflow:visible;white-space:pre-wrap;background:#fff;color:#111;font-size:10px}.kw,.num,.comment{color:#111}.figure-zoom{border:0}.figure-zoom img{max-height:280px}.has-wiring{grid-template-columns:1fr 1fr}details:not([open])>p{display:block}.challenge{background:#fff;border:1px solid #ccc}.source-note{font-size:10px}a{color:inherit!important}}

.str{color:#bfdda5}.zoom-scroll img.original-size{max-width:none}.dialog-bar h2{margin-right:auto}.dialog-bar{justify-content:flex-end}@media(max-width:560px){.dialog-bar{gap:8px}.dialog-bar button{font-size:12px;padding:7px 9px}.dialog-bar h2{font-size:15px}}

/* Landing effects: keep reading pages quiet and navigation usable without WebGL. */
body.landing{background:#eff7f1}.landing #main{position:relative;isolation:isolate}.landing-background{position:absolute;inset:0;z-index:-1;overflow:hidden;pointer-events:none;background:linear-gradient(140deg,#e5f5ec,#fbf9ed 55%,#dfede8)}.landing .course-card{background:rgba(255,255,255,.92)}.flight-area{position:relative;height:155px;margin:-35px -10px -12px;display:flex;align-items:center;justify-content:center}.flight-mount{position:absolute;inset:0;visibility:hidden}.flight-mount.ready{visibility:visible}.flight-area .flying-button{min-height:0;height:155px}.flight-area [hidden]{display:none}.flight-area .flying-button__craft{font-family:inherit;white-space:nowrap;cursor:pointer}.flight-area .flying-button__craft:focus-visible{outline:3px solid #e3a338;outline-offset:5px}.coming-art span{line-height:1.7}.landing .home-intro h1{text-shadow:0 1px 12px #fff}.landing .home-intro p{color:#3f5d55}@media(max-width:700px),(prefers-reduced-motion:reduce){.flight-area{height:auto;margin:0}.flight-mount{display:none}.site-header nav{gap:12px;font-size:12px}}

/* Keep the flying CTA above the board image, including during lift and drag. */
.course-card.arduino{isolation:isolate}
.arduino .board-art{position:relative;z-index:0}
.arduino .flight-area{z-index:10;overflow:visible}
.flight-area .flying-button{overflow:visible}
.flight-area .flying-button__smoke{z-index:0}
.flight-area .flying-button__craft{z-index:2}

/* Matching Scratch CTA with its own warm palette and foreground flight layer. */
.course-card.scratch{isolation:isolate}
.scratch .scratch-art{position:relative;z-index:0}
.scratch .flight-area{z-index:10;overflow:visible;margin-top:0;flex-shrink:0}
.scratch-start{background:#b94e0b;border-color:#b94e0b}
.scratch-start:hover{background:#963d07;border-color:#963d07}
@media(min-width:701px){.arduino .flight-area{margin-top:auto}}

/* Vehicle silhouettes remain part of the real clickable control. */
.vehicle-roadster{--vehicle-art:url('assets/roadster-button.svg');--vehicle-ink:#fff}
.vehicle-cybertruck{--vehicle-art:url('assets/cybertruck-button.svg');--vehicle-ink:#162e3c}
.flight-area .flying-button__craft,.flight-area .vehicle-button{width:300px;max-width:100%;height:107px;padding:0;border:0;border-radius:8px;background:var(--vehicle-art) center/100% 100% no-repeat;color:var(--vehicle-ink);filter:drop-shadow(0 7px 4px #152e3b20);font-size:13px;font-weight:750;line-height:1;letter-spacing:-.2px}
.flight-area .flying-button__face,.flight-area .flying-button__pod{display:none}
.flight-area .flying-button__label,.vehicle-label{position:absolute;left:0;right:0;top:61%;text-align:center;pointer-events:none}
.flight-area .vehicle-button{position:relative;flex:none;display:block;align-self:auto}
.flight-area .vehicle-button[hidden]{display:none}
.flight-area .flying-button__craft:hover,.flight-area .vehicle-button:hover{filter:brightness(1.06) drop-shadow(0 8px 5px #152e3b30)}
.flight-mount{top:-65px}.flight-area .flying-button{height:220px}
@media(max-width:700px),(prefers-reduced-motion:reduce){.flight-area .vehicle-button{width: min(300px,100%);aspect-ratio:360/128;height:auto}.flight-area{min-height:107px}}