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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}}

/* Smoke shares the foreground stage with the car, across the whole card. */
.flight-area .flight-mount{pointer-events:none}
.flight-area .flying-button{height:100%;pointer-events:none}
.flight-area .flying-button__craft{pointer-events:auto}
.flight-area .flying-button__smoke{z-index:1;pointer-events:none;mask-image:linear-gradient(to bottom,transparent,#000 32px,#000 calc(100% - 10px),transparent)}
/* Override the effect's hover-mode default cursor for navigation buttons. */
.flight-area .flying-button .flying-button__craft,.flight-area .vehicle-button{cursor:pointer}
.flight-area .flying-button[data-dragging] .flying-button__craft{cursor:grabbing}

/* A short first-visit welcome; all motion is skipped for reduced-motion users. */
body.intro-active{overflow:hidden}
.welcome-intro{position:fixed;inset:0;z-index:1000;display:grid;place-items:center;overflow:hidden;background:radial-gradient(ellipse at 25% 70%,#ffdfba70,transparent 48%),radial-gradient(ellipse at 80% 30%,#b4e5d480,transparent 52%),#f6faf4;color:#183c3c;transition:opacity .45s ease,transform .45s ease}
.intro-grid{position:absolute;inset:-15%;font:700 clamp(60px,10vw,150px)/2 monospace;letter-spacing:50px;word-spacing:50px;color:#087f8309;transform:rotate(-12deg);pointer-events:none;overflow-wrap:anywhere}
.intro-content{position:relative;text-align:center;width:min(680px,90vw)}
.intro-eyebrow{font-size:15px;letter-spacing:5px;color:#52776d;margin:0 0 20px;animation:intro-rise .5s both}
.intro-brand{display:flex;align-items:baseline;justify-content:center;gap:16px;font-size:clamp(40px,7vw,82px);line-height:1.1;letter-spacing:-4px;animation:intro-rise .65s .12s both}
.intro-brand strong{font-weight:850}.intro-brand>span{color:#087f83;font-weight:350}.intro-caret{color:#d67820;animation:intro-caret .6s steps(1) infinite}
.intro-message{font-size:clamp(14px,2vw,20px);color:#526b62;margin:24px 0 0;animation:intro-rise .6s .3s both}
.intro-vehicles{display:flex;justify-content:center;gap:32px;align-items:end;margin:38px 0 28px;min-height:100px}
.intro-vehicles img{width:42%;max-width:260px;height:auto;filter:drop-shadow(0 12px 7px #193d3620)}
.intro-roadster{animation:intro-drive-left .85s .18s cubic-bezier(.16,1,.3,1) both}.intro-truck{animation:intro-drive-right .85s .32s cubic-bezier(.16,1,.3,1) both}
.intro-progress{width:100px;height:3px;background:#dbe9e0;margin:0 auto;overflow:hidden;border-radius:4px}.intro-progress i{display:block;width:100%;height:100%;background:linear-gradient(90deg,#d77825,#087f83);transform-origin:left;animation:intro-progress 4.3s linear both}
.intro-skip{position:absolute;bottom:32px;right:36px;background:#ffffffa8;border:1px solid #ccded5;color:#36594f;border-radius:30px;padding:10px 20px;font:inherit;font-size:14px;cursor:pointer}
.welcome-intro.intro-leaving{opacity:0;transform:scale(1.035);pointer-events:none}
@keyframes intro-rise{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}
@keyframes intro-drive-left{from{opacity:0;transform:translateX(-140px) translateY(18px)}to{opacity:1;transform:translateX(0) translateY(0)}}
@keyframes intro-drive-right{from{opacity:0;transform:translateX(140px) translateY(18px)}to{opacity:1;transform:translateX(0) translateY(0)}}
@keyframes intro-progress{from{transform:scaleX(0)}to{transform:scaleX(1)}}
@keyframes intro-caret{50%{opacity:0}}
@media(max-width:560px){.intro-brand{gap:9px;letter-spacing:-2px}.intro-eyebrow{font-size:12px;letter-spacing:3px}.intro-vehicles{gap:12px;margin-top:24px;min-height:76px}.intro-skip{bottom:24px;right:20px}.intro-message{margin-top:18px}}
@media(prefers-reduced-motion:reduce){.welcome-intro{display:none}}

/* Magic UI Retro Grid: adapted from its MIT-licensed CSS fallback.
   Source: https://magicui.design/r/retro-grid.json; license: magic-ui-license.txt */
.landing-background{background:radial-gradient(ellipse at 12% 35%,#f8dfbf70,transparent 50%),radial-gradient(ellipse at 85% 20%,#c3e8df90,transparent 55%),#f4f8f4}
.retro-grid{position:absolute;inset:0;overflow:hidden;pointer-events:none;--grid-color:#258e8859;--grid-cell:72px;opacity:.7}
.retro-projection{position:absolute;inset:0;perspective:200px}
.retro-rotation{position:absolute;inset:0;transform:rotateX(65deg)}
.retro-lines{position:absolute;inset:0 0 auto;margin-left:-200%;width:600vw;height:300vh;transform-origin:100% 0 0;background-image:linear-gradient(to right,var(--grid-color) 1px,transparent 0),linear-gradient(to bottom,var(--grid-color) 1px,transparent 0);background-size:var(--grid-cell) var(--grid-cell);background-repeat:repeat;transform:translateY(-50%);animation:codelab-grid-scroll 15s linear infinite}
.retro-fade{position:absolute;inset:0;background:linear-gradient(to top,#f4f8f4,transparent 80%)}
.welcome-intro .retro-grid{opacity:.85;--grid-color:#258e8866;--grid-cell:64px}
.welcome-intro .retro-fade{background:linear-gradient(to top,#f6faf4,transparent 85%)}
.intro-brand{letter-spacing:-3px}.intro-brand>span{font-weight:700}.brand{letter-spacing:-1px}.brand span{font-weight:700}
.intro-content{z-index:1}.intro-skip{z-index:2}
@keyframes codelab-grid-scroll{from{transform:translateY(-50%)}to{transform:translateY(0)}}
@media(max-width:560px){.retro-grid{--grid-cell:56px}.intro-brand{font-size:48px;letter-spacing:-2px}.intro-eyebrow{letter-spacing:2px}}
@media(prefers-reduced-motion:reduce){.retro-lines{animation:none;transform:translateY(-50%)}}

/* Keep the five-second welcome moving and prepare the real controls before reveal. */
.welcome-intro{transition:opacity .7s ease;will-change:opacity}
.welcome-intro.intro-leaving{transform:none}
.intro-roadster{animation:intro-roadster-flow 4.3s .1s ease-in-out both}
.intro-truck{animation:intro-truck-flow 4.3s .25s ease-in-out both}
@keyframes intro-roadster-flow{0%{opacity:0;transform:translate(-140px,18px)}22%{opacity:1;transform:translate(0,0)}48%{opacity:1;transform:translate(4px,-8px)}75%{opacity:1;transform:translate(0,-2px)}100%{opacity:1;transform:translate(3px,-9px)}}
@keyframes intro-truck-flow{0%{opacity:0;transform:translate(140px,18px)}22%{opacity:1;transform:translate(0,0)}48%{opacity:1;transform:translate(-3px,-5px)}75%{opacity:1;transform:translate(0,1px)}100%{opacity:1;transform:translate(-3px,-7px)}}

/* Lesson tabs: sliding selected tab and a rising card over a quiet card stack. */
.lesson-tabs-toolbar{display:flex;align-items:center;gap:12px;margin:24px 0 20px;scroll-margin-top:18px}
.lesson-tabs-scroll{min-width:0;max-width:100%;overflow-x:auto;overscroll-behavior-x:contain;scrollbar-width:thin;scrollbar-color:#b4d3ce transparent;padding:4px 0 8px}
.lesson-tabs{position:relative;display:flex;width:max-content;min-width:100%;gap:4px;padding:4px;border-radius:16px;background:#f2f6f5}
.lesson-tab{position:relative;z-index:1;border:0;background:transparent;border-radius:12px;padding:12px 17px;color:#52676c;font-size:14px;font-weight:700;white-space:nowrap;cursor:pointer;transition:color .2s}
.lesson-tab[aria-selected=true]{color:#fff}.lesson-tab:not([aria-selected=true]):hover{color:#087f83;background:#e3efeb}
.lesson-tab-marker{position:absolute;top:4px;bottom:4px;left:0;border-radius:12px;background:#087f83;box-shadow:0 3px 8px #087f8326;transition:transform .28s cubic-bezier(.22,1,.36,1),width .28s;pointer-events:none}
.lesson-tabs-toolbar #print-lesson{border:1px solid #dce6e8;background:#fff;border-radius:10px;padding:9px 13px;font-size:13px;white-space:nowrap;margin-left:auto;color:#52676c}
.lesson-tab-deck{position:relative;isolation:isolate;margin:0 0 38px;perspective:1200px}
.lesson-tab-deck:before,.lesson-tab-deck:after{content:'';position:absolute;inset:0;border:1px solid #d3e5df;border-radius:22px;background:#e6f2ee;pointer-events:none;transform-origin:center bottom}
.lesson-tab-deck:before{z-index:-1;transform:translateY(10px) scaleX(.975)}.lesson-tab-deck:after{z-index:-2;transform:translateY(20px) scaleX(.945);background:#f1f7f4}
.lesson-tab-panel{position:relative;min-width:0;padding:25px 28px 28px;border:1px solid #d9e7e2;border-radius:22px;background:#fff;box-shadow:0 10px 32px #254e3e09;transform-origin:center top;overflow-wrap:anywhere}
.lesson-tab-panel[hidden]{display:none}.lesson-tab-panel:focus-visible{outline:3px solid #19a1a5;outline-offset:4px}
.lesson-tab-caption{margin:0 0 12px;font-size:11px;font-weight:750;letter-spacing:1.5px;color:#60867a}
.lesson-tab-panel .lesson-section{padding:12px 0 20px;border-top:0}.lesson-tab-panel .lesson-section:last-child{padding-bottom:0}
.lesson-tab-panel .challenge{padding:22px;margin-top:12px}.lesson-tab-panel .result{border-top:1px solid var(--line);padding-top:24px}
.lesson-tab-next{display:block;margin:20px 0 0 auto;border:1px solid #b5d9ce;background:#edf8f3;border-radius:10px;color:#087f83;font-size:14px;font-weight:700;padding:11px 16px;cursor:pointer}
.lesson-tab-next:hover{background:#dff2e9}.lesson-tab-panel .has-wiring{grid-template-columns:minmax(0,1.1fr) minmax(200px,1fr)}
.code-empty p{font-size:16px;color:#60717c;line-height:1.9}
@media(max-width:1100px){.lesson-tab{padding:11px 12px;font-size:13px}.lesson-tabs-toolbar{gap:8px}.lesson-tab-panel{padding:22px}.lesson-tab-panel .has-wiring{grid-template-columns:1fr}}
@media(max-width:560px){.lesson-tabs-toolbar{margin:18px 0 16px;gap:8px}.lesson-tab{padding:11px 14px;font-size:13px}.lesson-tabs-toolbar #print-lesson{padding:9px;font-size:12px}.lesson-tab-panel{padding:18px 14px;border-radius:16px}.lesson-tab-deck:before,.lesson-tab-deck:after{border-radius:16px}.lesson-tab-panel .lesson-section h2{font-size:19px}.lesson-tab-panel .challenge{padding:16px}.lesson-tab-caption{font-size:10px;letter-spacing:.9px}.lesson-tab-next{font-size:13px}.lesson-tab-panel .code-toolbar>div{justify-content:flex-start;gap:12px}.lesson-tab-panel .code-toolbar button,.lesson-tab-panel .code-toolbar a{font-size:11px}.lesson-tab-panel .code-title{flex-wrap:wrap;gap:8px}}
@media(prefers-reduced-motion:reduce){.lesson-tab-marker,.lesson-tab{transition:none}}
@media print{.lesson-tabs-toolbar,.lesson-tab-next{display:none!important}.lesson-tab-deck{perspective:none;margin:0}.lesson-tab-deck:before,.lesson-tab-deck:after{display:none}.lesson-tab-panel,.lesson-tab-panel[hidden]{display:block!important;min-height:0;padding:0;border:0;border-radius:0;box-shadow:none;transform:none!important;opacity:1!important}.lesson-tab-caption{margin-top:16px}.lesson-tab-panel .has-wiring{grid-template-columns:1fr 1fr}}

/* The classroom entry page uses the same stacked tabs for its seven units. */
.unit-tabs-toolbar{margin-top:30px}.unit-tabs-toolbar .lesson-tabs-scroll{width:100%}
.unit-tab-deck .unit{padding:28px;margin:0;border:1px solid #d9e7e2;background:linear-gradient(135deg,#f0faf6,#fff 45%)}
.unit-tab-deck .unit-heading{margin:0 0 12px}.unit-tab-deck .unit-heading>span{background:#087f83;color:#fff;border-radius:14px;width:48px;height:48px;display:grid;place-items:center;font-size:20px}
.unit-tab-description{color:#60796f;font-size:14px;margin:0 0 22px}
.unit-tab-deck .unit-lessons{border:1px solid #dce8e2;border-radius:14px;overflow:hidden;background:white}
.unit-tab-deck .unit-lessons a{padding:18px 16px}.unit-tab-deck .unit-lessons a:last-child{border-bottom:0}
@media(max-width:560px){.unit-tab-deck .unit{padding:20px 14px}.unit-tab-deck .unit-heading h2{font-size:20px}.unit-tab-description{font-size:12px}.unit-tab-deck .unit-lessons a{padding:15px 10px}}
@media print{.unit-tab-deck .unit{padding:0;margin:20px 0;border:0;background:white}.unit-tab-deck .unit-lessons{border:0}}
.unit-tab-deck .unit{display:block}
.unit-tab-deck .unit[hidden]{display:none}
.unit-tab-deck .unit-heading{display:flex;align-items:center;gap:14px}
.unit-tab-deck .unit-heading h2{margin:0}
.unit-tab-deck .unit-lessons{width:100%;min-width:0}
@media print{.unit-tab-deck .unit[hidden]{display:block!important}}

/* Grid Scan landing: welcome -> one completed shader scan -> navigation. */
body.landing{background:#080f18}
.landing #grid-background{position:fixed;inset:0;background:#080f18}
.landing .home-intro h1{color:#effffb;text-shadow:none}
.landing .home-intro p{color:#bbd6d7}
.landing .resume,.landing .learning-path,.landing .site-footer{color:#b9ded8}
.landing .course-card{background:rgba(255,255,255,.95)}
body.intro-active,body.scan-active{overflow:hidden;background:#080f18}
.intro-active .site-header,.intro-active .home,.intro-active .site-footer,
.scan-active .site-header,.scan-active .home,.scan-active .site-footer{opacity:0;visibility:hidden;pointer-events:none}
.scan-skip{position:fixed;bottom:28px;right:28px;z-index:1001;border:1px solid #6fe3cd66;border-radius:30px;padding:12px 20px;background:#102b31;color:#dbfff4;cursor:pointer;font:inherit}
.landing-revealed.landing .site-header,.landing-revealed.landing .home,.landing-revealed.landing .site-footer{animation:codelab-menu-reveal .8s cubic-bezier(.2,.7,.2,1) both}
@keyframes codelab-menu-reveal{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:translateY(0)}}
@media(prefers-reduced-motion:reduce){.landing-revealed.landing .site-header,.landing-revealed.landing .home,.landing-revealed.landing .site-footer{animation:none}.landing #grid-background{background-color:#080f18;background-image:linear-gradient(#405b6b44 1px,transparent 1px),linear-gradient(90deg,#405b6b44 1px,transparent 1px);background-size:64px 64px}}

@media(max-width:700px){.flight-area a.vehicle-button[hidden]{display:inline-flex!important}}

/* Transparent course cards over Grid Scan, with readable foreground labels. */
.landing .course-card{background:transparent;box-shadow:none}
.landing .course-card.scratch h2{color:#ffa650}
.landing .course-card.arduino h2{color:#66e2d3}
.landing .course-card>p,.landing .coming-art{color:#d9e9ec;text-shadow:0 2px 8px #080f18}
.landing .coming-art{border-color:#8aa9b566}

/* Official brand artwork replaces the placeholder blocks and board photo. */
.landing .course-brand-art{height:340px;display:flex;align-items:center;justify-content:center;position:relative;z-index:0;margin:20px 0 30px;flex-shrink:0}
.landing .scratch-brand-art{flex-direction:column;gap:16px}
.landing .scratch-wordmark{width:220px;height:auto;max-width:80%;object-fit:contain}
.landing .scratch-mascot{width:auto;height:200px;max-width:80%;object-fit:contain;filter:drop-shadow(0 12px 18px #0005)}
.landing .arduino-brand-logo{width:320px;max-width:85%;height:auto;object-fit:contain;filter:drop-shadow(0 0 24px #66e2d322)}
@media(max-width:800px){.landing .course-brand-art{height:300px}.landing .scratch-wordmark{width:190px}.landing .scratch-mascot{height:180px}}
@media(max-width:560px){.landing .course-brand-art{height:280px;margin:18px 0 24px}.landing .scratch-wordmark{width:185px}.landing .scratch-mascot{height:175px}.landing .arduino-brand-logo{width:260px}}