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@media(min-width:1500px){.page-layout{max-width:1360px;grid-template-columns:250px minmax(0,1fr);gap:85px;padding:0 55px}.lesson-hero{gap:40px}.hero-art{height:325px}.hero-copy h1{font-size:66px}.hero-tile{width:200px;height:200px}.lesson-main{padding-top:48px}.lesson-section>p{font-size:15px}.section-heading h2{font-size:28px}}
@media(max-width:1100px){.page-layout{gap:38px;grid-template-columns:205px minmax(0,1fr);padding:0 28px}.site-header{padding:0 28px}.header-nav{gap:23px}.hero-copy h1{font-size:51px}.hero-art{height:257px}.hero-tile{width:158px;height:158px}.art-note{font-size:9px}.fraction-sticker{right:-6px;bottom:-4px;padding:9px 11px}.sidebar-note{font-size:12px}.lesson-toc a{font-size:12px;gap:11px}.lab-bottom{flex-direction:column;align-items:flex-start;gap:5px}.step-scene{gap:18px;padding-left:19px;padding-right:19px}.snack-strip{width:215px}.scene-caption{width:145px}.scene-caption strong{font-size:15px}.step-tabs button{font-size:10px;gap:4px}.fraction-labels small{font-size:10px}}
@media(max-width:850px){.page-layout{display:block;max-width:760px;padding:0 25px}.lesson-sidebar{display:none}.lesson-main{padding-top:28px}.breadcrumb{margin-bottom:28px}.lesson-hero{grid-template-columns:1.1fr 1fr;min-height:300px;margin-bottom:31px;gap:30px}.hero-copy h1{font-size:56px}.hero-art{height:280px}.hero-tile{width:174px;height:174px}.site-header{height:79px;padding:0 25px}.brand{font-size:18px}.brand-icon{width:37px;height:37px}.brand-icon svg{width:25px}.brand small{font-size:9px;letter-spacing:.6px}.header-nav{gap:24px;font-size:12px}.header-nav .header-quiz{padding:7px 13px;gap:12px}.reading-progress{top:78px}.snack-strip{width:260px}.scene-caption{width:170px}.step-tabs button{font-size:11px}.fraction-labels small{font-size:11px}}
@media(max-width:600px){body{font-size:15px}.site-header{height:72px;padding:0 18px;gap:12px}.brand{font-size:16px;gap:8px}.brand-icon{height:34px;width:34px;border-radius:10px}.brand small{font-size:8px;margin-top:3px}.header-nav>a:not(.header-quiz){display:none}.header-nav .header-quiz{font-size:10px;padding:7px 11px;gap:9px;white-space:nowrap}.header-nav{gap:0}.reading-progress{top:71px}.page-layout{padding:0 20px}.lesson-main{padding-top:23px}.breadcrumb{font-size:9px;gap:9px;margin-bottom:23px}.lesson-hero{grid-template-columns:1.05fr .95fr;gap:9px;min-height:270px;margin-bottom:27px;align-items:center}.eyebrow{font-size:9px;margin-bottom:13px;gap:5px}.hero-copy h1{font-size:43px;letter-spacing:-1.7px;line-height:1.25}.hero-description{font-size:11px;line-height:1.9;margin-top:17px}.lesson-meta{font-size:8px;gap:7px;margin-top:17px;flex-wrap:wrap;row-gap:7px}.lesson-meta>span+span{padding-left:7px}.lesson-meta svg{width:12px;height:12px}.hero-art{height:205px;margin-top:0;border-radius:43% 42% 41% 45%}.hero-tile{width:116px;height:116px;gap:4px;padding:5px;border-radius:12px;box-shadow:6px 8px 0 #d2dcc5}.hero-tile i{border-radius:4px}.art-note{font-size:8px;left:-15px;top:-8px;max-width:130px}.art-note>span{font-size:22px;right:-13px;top:4px}.art-spark{font-size:33px;right:0;top:7px}.fraction-sticker{font-size:8px;padding:8px 9px;gap:7px;bottom:6px;right:-3px;border-radius:10px}.fraction-sticker .fraction{font-size:23px;min-width:22px}.fraction-sticker svg{width:14px}.learning-goal{font-size:11px;padding:13px 14px;gap:10px;margin-bottom:37px;align-items:flex-start;border-radius:10px}.goal-icon{width:21px;height:21px;font-size:11px;margin-top:2px}.learning-goal strong{display:block;margin-bottom:3px}.lesson-section{padding-bottom:34px;margin-bottom:32px;scroll-margin-top:91px}.section-heading{gap:11px;margin-bottom:17px}.section-heading h2{font-size:22px;letter-spacing:-.6px}.section-number{width:33px;height:33px;font-size:13px}.section-kicker{font-size:9px;margin-bottom:4px}.lesson-section>p{font-size:13px;line-height:1.95}.desktop-break{display:none}.step-demo{margin-top:20px;border-radius:13px}.step-tabs{gap:4px;padding:5px}.step-tabs button{font-size:9px;padding:10px 4px;flex-direction:column;gap:5px}.step-tabs button>span{width:18px;height:18px;font-size:9px}.step-scene{padding:29px 18px 13px;gap:18px;flex-direction:column;min-height:187px}.snack-strip{width:min(100%,285px);height:67px}.scene-caption{text-align:center;width:100%}.scene-caption strong{font-size:16px}.scene-caption>span{font-size:10px;margin-top:3px}.demo-instruction{font-size:9px;padding:0 15px 14px}.concept-line{font-size:12px;gap:9px;margin-top:16px}.fraction-explainer{padding:23px 12px 27px;gap:9px;border-radius:13px}.big-fraction{font-size:61px;width:70px}.fraction-labels{gap:23px}.fraction-labels>div{gap:10px}.annotation-line{width:20px}.fraction-labels b{font-size:13px}.fraction-labels strong{font-size:10px}.fraction-labels small{font-size:10px;max-width:184px;line-height:1.7}.remember-line{align-items:flex-start;gap:10px;font-size:11px;margin-top:17px}.remember-line p{gap:2px;flex-direction:column}.remember-separator{display:none}.pill{font-size:9px;padding:3px 8px}.interactive-lab{margin-top:20px;border-radius:13px}.lab-top{padding:13px 14px;gap:8px;flex-wrap:wrap;font-size:11px}.lab-top select{font-size:11px;padding:5px 19px 5px 7px}.text-button{font-size:10px;padding:4px}.text-button>span{font-size:15px}.lab-canvas{padding:28px 14px;gap:14px;min-height:132px}.parts-grid{gap:3px;padding:4px;border-radius:7px}.part-button{min-height:65px;border-radius:3px}.part-button>span{font-size:14px}.live-fraction{padding:12px 9px;min-width:49px;border-radius:10px}.live-fraction .fraction{font-size:30px}.lab-bottom{padding:12px 14px;font-size:11px;gap:4px}.lab-bottom>span{font-size:9px}.lesson-section>p.try-challenge{font-size:11px;margin-top:12px;line-height:1.9}.comparison{gap:10px;margin-top:20px}.comparison-item{padding:15px 12px;border-radius:12px}.comparison-title{font-size:10px;line-height:1.8;align-items:flex-start;gap:6px;min-height:36px}.comparison-title>span{width:18px;height:18px;font-size:13px;line-height:16px;flex:none;margin-top:2px}.comparison-bar{height:45px;margin:16px 0 11px;padding:3px;gap:2px}.comparison-item p{font-size:10px}.lesson-summary{margin-top:23px;padding:21px;grid-template-columns:1fr;gap:17px;border-radius:13px}.lesson-summary>div{display:flex;align-items:center;gap:11px}.lesson-summary>div>span{font-size:27px;margin:0}.lesson-summary h3{font-size:17px;max-width:none}.lesson-summary ul{font-size:12px;gap:8px}.quiz-card{padding:21px 17px;min-height:360px;border-radius:13px;margin-top:19px}.quiz-top{font-size:10px;margin-bottom:21px}.quiz-dots>span{width:19px}.question-heading{font-size:17px;line-height:1.75}.question-visual{height:53px;margin:20px 0}.quiz-options{margin-top:18px;gap:8px}.quiz-options legend{font-size:10px;margin-bottom:8px}.quiz-option{padding:11px 12px;font-size:12px;gap:10px;min-height:49px}.quiz-option .answer-marker{font-size:9px}.quiz-actions{margin-top:19px}.primary-button{font-size:11px;padding:11px 19px;gap:20px}.feedback{padding:13px;font-size:11px}.feedback strong{font-size:13px}.quiz-privacy{font-size:9px!important;margin-top:12px;line-height:1.9!important}.quiz-section{margin-bottom:35px;padding-bottom:0}.lesson-footer{padding:23px 0 31px;gap:20px}.footer-brand{font-size:14px}.footer-brand>span{font-size:9px}.back-top{font-size:10px}.lesson-footer>p{font-size:9px}.result-score{width:110px;height:110px}.results h3{font-size:21px}.result-actions{gap:12px}.secondary-button{font-size:11px;padding:11px 15px}.review-item{font-size:10px}.not-found{padding:25px}.not-found h1{font-size:36px}}
@media(max-width:360px){.site-header{padding:0 13px}.brand{font-size:14px}.brand-icon{height:30px;width:30px}.header-nav .header-quiz{font-size:9px;padding:7px 9px}.page-layout{padding:0 16px}.hero-copy h1{font-size:38px}.hero-art{height:190px}.hero-tile{width:101px;height:101px}.art-note{font-size:7px;left:-5px}.hero-description{font-size:10px}.lesson-meta{font-size:8px}.section-heading h2{font-size:20px}.text-button{margin-left:0}.lab-top label{width:100%}.lab-top .text-button{margin-left:auto}.lab-canvas{gap:9px;padding:25px 10px}.part-button>span{font-size:12px}.comparison-title{font-size:9px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation:none!important;transition:none!important}.part-button:hover{transform:none}}
/* Keep Thai teaching text comfortable to read, including on small screens. */
.quiz-card{scroll-margin-top:110px}
.hero-description{font-size:17px}.lesson-section>p{font-size:16px}.lesson-toc a{font-size:14px}.learning-goal{font-size:14px}.step-tabs button{font-size:12px}.scene-caption>span,.demo-instruction{font-size:12px}.concept-line{font-size:15px}.fraction-labels small{font-size:13px}.remember-line{font-size:14px}.lab-top,.lab-top select{font-size:14px}.lab-bottom{font-size:13px}.comparison-title,.comparison-item p{font-size:13px}.lesson-summary ul{font-size:14px}.quiz-option{font-size:15px}.quiz-options legend{font-size:12px}.feedback{font-size:14px}.quiz-privacy{font-size:12px!important}.review-item{font-size:13px}.results>p:not(.result-label){font-size:14px}.lesson-section>p.try-challenge{font-size:14px}
@media(max-width:1100px) and (min-width:851px){.lesson-toc a{font-size:12px}.step-tabs button{font-size:11px}}
@media(max-width:600px){.hero-description{font-size:13px}.lesson-section>p{font-size:15px}.learning-goal{font-size:12px}.step-tabs button{font-size:10px}.scene-caption>span,.demo-instruction{font-size:11px}.concept-line{font-size:13px}.fraction-labels small{font-size:11px}.remember-line{font-size:12px}.lab-top,.lab-top select{font-size:12px}.lab-bottom{font-size:12px}.comparison-title,.comparison-item p{font-size:11px}.lesson-summary ul{font-size:13px}.quiz-option{font-size:14px}.feedback{font-size:13px}.quiz-privacy{font-size:10px!important}.review-item{font-size:12px}.results>p:not(.result-label){font-size:13px}.lesson-section>p.try-challenge{font-size:12px}.answer-marker{display:none}.question-heading{font-size:18px}}