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var(--line)}.dataset-list{display:flex;gap:6px;flex-wrap:wrap;margin-top:10px}.dataset-chip{display:flex;align-items:center;gap:6px;background:var(--paper);border-radius:7px;padding:6px 9px;font-size:10px;min-height:30px;border:1px solid var(--line)}.dataset-chip button{background:transparent;padding:0 2px;color:var(--muted);font-size:13px}.test-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:9px;margin-top:17px}.test-card{padding:14px;border:1px solid var(--line);border-radius:10px;background:var(--paper);font-size:11px;line-height:1.7}.test-card.error{background:#fcf0dc;border-color:#e3d2a6}.test-card strong{font-size:12px}.fair-examples{display:flex;align-items:center;gap:12px;justify-content:center;flex-wrap:wrap;padding:15px}.shape-example{background:var(--white);border:1px solid var(--line);padding:12px;border-radius:12px;display:flex;align-items:center;gap:9px;font-size:11px}.shape-example 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label{font-size:14px;font-weight:650}.project-stage p{font-size:11px;color:var(--muted);margin-top:10px}.project-stage textarea{min-height:115px}.journal-summary{display:flex;gap:13px;padding:22px;background:#e8efdd;border:1px solid #d7e2c9;border-radius:16px;align-items:center;margin-bottom:22px}.journal-summary>svg{width:30px;height:30px;flex-shrink:0}.journal-summary h3{font-size:16px}.journal-summary p{font-size:12px;color:var(--muted);margin-top:5px}.journal-list{display:grid;gap:13px}.journal-item{background:var(--white);border:1px solid var(--line);border-radius:16px;padding:22px}.journal-item header{display:flex;gap:12px;align-items:center;margin-bottom:13px}.journal-item .mini-icon{width:39px;height:39px;border-radius:11px;padding:9px}.journal-item .mini-icon svg{width:21px;height:21px}.journal-item h3{font-size:16px}.journal-item time{font-size:10px;color:var(--muted)}.journal-item p{font-size:13px;color:var(--muted);white-space:pre-wrap;overflow-wrap:anywhere}.journal-item .btn{margin-top:10px}.empty-state{padding:50px 30px;background:var(--white);border:1px dashed #b8c4ad;border-radius:20px;text-align:center}.empty-state .empty-robot{width:100px;height:100px;margin:0 auto 17px}.empty-state h3{margin-bottom:12px}.empty-state p{font-size:13px;color:var(--muted);max-width:440px;margin:auto}.empty-state .btn{margin-top:20px}.guide-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.guide-card{background:var(--white);padding:26px;border:1px solid var(--line);border-radius:18px}.guide-card h3{display:flex;gap:10px;align-items:center;margin-bottom:16px}.guide-card h3 svg{width:23px;height:23px}.guide-card p,.guide-card li{font-size:13px;line-height:1.8;color:var(--muted)}.guide-card ul,.guide-card ol{padding-left:19px;margin:13px 0 0}.guide-card li{margin:8px 0}.guide-wide{grid-column:1/-1}.mapping-table{width:100%;font-size:12px;border-collapse:collapse;margin:20px 0}.mapping-table td,.mapping-table th{border-bottom:1px solid var(--line);padding:13px 12px;text-align:left;line-height:1.7}.mapping-table th{font-size:10px;color:var(--muted);text-transform:uppercase;letter-spacing:.7px}.source-list{display:grid;gap:10px;margin-top:15px}.source-list a{font-size:12px;line-height:1.6;color:#496754;text-decoration:underline;text-underline-offset:3px}.guide-policy{font-size:11px!important;margin-top:20px!important}.table-wrap{overflow-x:auto}.project-print{display:none}#toast{position:fixed;bottom:22px;left:50%;transform:translateX(-50%) translateY(30px);opacity:0;pointer-events:none;z-index:100;background:var(--ink);color:white;padding:13px 20px;border-radius:12px;box-shadow:0 10px 30px #203d3620;font-size:12px;max-width:min(90vw,540px);transition:all .2s;line-height:1.5}#toast.show{opacity:1;transform:translateX(-50%) translateY(0)}.noscript{margin:40px;padding:30px}.wide-actions{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:24px}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.chart-column{display:block;position:relative}.chart-column .bar{position:absolute;bottom:0;left:50%;transform:translateX(-50%)}.chart-column .bar-value{position:absolute;left:50%;transform:translateX(-50%)}.chart-column .bar-label{left:50%;transform:translateX(-50%)}
@media(min-width:1600px){main{padding:40px 55px}.hero{min-height:400px}.card-art{height:145px}}
@media(max-width:1180px){.sidebar{width:190px;padding:28px 17px}.brand{font-size:20px}.brand-sub{font-size:8px;margin-left:45px}.workspace{margin-left:190px;width:calc(100% - 190px)}main{padding:26px}.topbar{padding:20px 26px}.hero{padding:28px;gap:10px}.hero h1{font-size:44px}.hero-art{min-height:270px}.floating-label{font-size:9px;padding:10px}.lab-grid{grid-template-columns:repeat(2,1fr)}.fair-grid{grid-template-columns:repeat(2,1fr)}.callout .btn{font-size:11px}}
@media(max-width:860px){.sidebar{position:relative;width:100%;padding:17px 22px;inset:auto;border-right:0;border-bottom:1px solid var(--line);display:block}.brand{font-size:21px}.brand-sub,.side-label,.side-tip,.side-footer{display:none}.nav{display:flex;gap:4px;overflow-x:auto;margin-top:16px;padding-bottom:2px}.nav button{padding:10px 13px;font-size:11px;gap:7px}.nav button svg{width:15px;height:15px}.shell{display:block}.workspace{margin:0;width:100%}.topbar{padding:16px 22px;min-height:60px}.topbar-context{font-size:10px}.hero h1{font-size:46px}.hero-art{min-height:260px}.hero-note{flex-direction:column;gap:6px}.reflection{grid-template-columns:1fr 1fr}.callout{padding:24px}.callout-icon{display:none}.callout h3{font-size:19px}.split{gap:20px}.top-controls{gap:8px}.avatar{display:none}}
@media(max-width:620px){:root{font-size:14px}.sidebar{padding:17px 16px 11px}.brand{font-size:23px}.nav button{padding:10px 11px}.nav button svg{display:none}.topbar{padding:12px 16px;flex-wrap:wrap;gap:8px}.topbar-context{font-size:10px}.top-controls{gap:6px;flex:1;justify-content:flex-end}.grade-select{font-size:10px;padding:8px 9px;max-width:145px}.lang-switch button{font-size:10px;padding:6px 7px}main{padding:22px 16px}.welcome{font-size:11px;margin-bottom:16px}.hero{grid-template-columns:1fr;padding:25px 24px 13px;gap:4px}.hero h1{font-size:47px;letter-spacing:-2.2px;margin:19px 0 17px}.hero p{font-size:13px}.hero-buttons{gap:11px;margin-top:21px}.hero-note{flex-direction:row;flex-wrap:wrap;gap:11px;margin-top:16px}.hero-art{min-height:242px;max-width:360px;width:100%;margin:5px auto 0}.hero-art:before{width:220px;height:220px}.hero-art:after{width:160px;height:160px}.bibo-hero{width:230px}.floating-label.one{top:27px;right:0;font-size:9px}.floating-label.two{bottom:12px;left:0;font-size:9px}.orbit-star{left:17px;top:20px}.tracks{grid-template-columns:1fr}.track{padding:17px}.track-icon{width:45px;height:45px;padding:10px}.section-top{margin-top:26px;align-items:start}.section-top h2{font-size:22px}.section-top p{font-size:11px}.lab-grid{gap:12px}.card-art{height:102px}.card-art .art{width:104px;height:88px}.card-art:before{width:87px;height:87px}.card-body{padding:16px 13px}.card-body h3{font-size:16px}.card-body p{font-size:11px;margin-bottom:13px}.card-body .eyebrow{font-size:7px;letter-spacing:.8px}.card-time{font-size:8px;top:9px;right:8px;padding:3px 5px}.card-num{left:10px;top:10px;font-size:9px}.card-open{font-size:10px}.card-open svg{width:14px}.callout{display:block;padding:23px}.callout .btn{margin:17px 0 0}.callout p{font-size:11px}.bottom-note{display:block;font-size:9px}.bottom-note span{display:block;margin-top:9px}.page-title{font-size:35px}.page-subtitle{font-size:13px}.lesson-head h1{font-size:31px;letter-spacing:-1px}.lesson-head p{font-size:12px}.lesson-glyph{width:53px;height:53px;padding:12px;border-radius:15px}.lesson-glyph svg{width:29px;height:29px}.lesson-top{flex-wrap:wrap;gap:7px}.concept{padding:17px;gap:10px}.concept p{font-size:12px}.experiment-heading{padding:17px}.experiment-heading h2{font-size:15px}.experiment-body{padding:18px 15px}.split,.reflection,.guide-grid,.project-stages{grid-template-columns:1fr}.reflection-panel{padding:20px}.robot-grid{max-width:330px}.directions{gap:8px}.test-grid{grid-template-columns:repeat(2,1fr)}.fair-grid{gap:9px}.sequence{gap:7px;padding:25px 0}.sequence-item{width:41px;height:53px;font-size:19px;border-radius:10px}.sequence-item svg{width:27px;height:27px}.answers{gap:8px}.answer{min-width:65px;min-height:57px;font-size:18px}.case-card{padding:21px 15px}.case-card h3{font-size:18px}.case-card p{font-size:12px}.answer.text-answer{flex-basis:100%;font-size:12px;padding:13px;min-height:48px}.guide-card{padding:22px}.guide-card h3{font-size:18px}.mapping-table{font-size:11px;min-width:430px}.bar-chart{height:210px}.dataset-chip{font-size:9px}.btn{font-size:12px;padding:11px 15px}.fair-card{padding:16px 10px}.fair-card p{font-size:10px}.catalog-head{align-items:start}.catalog-head .btn{font-size:10px;white-space:nowrap}.guide-wide{grid-column:auto}}
@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
@media print{body{background:white;color:#182b23}.sidebar,.topbar,.bottom-note,.back,.wide-actions,.activity-controls,.btn,.lang-switch,#toast,.skip-link,.hero,.nav,.save-row,.filter,.directions,.queue,.card-open{display:none!important}.workspace{margin:0;width:100%}main{padding:0;max-width:none;min-height:0}.guide-grid,.reflection{display:block}.guide-card,.reflection-panel,.journal-item,.project-stage{break-inside:avoid;margin:0 0 16px;border-color:#ccc;box-shadow:none}.guide-card h3{font-size:17px}.guide-card p,.guide-card li{font-size:11px}.source-list a{font-size:10px;overflow-wrap:anywhere}.table-wrap{overflow:visible}.mapping-table{font-size:10px;min-width:0}.guide-wide{display:block}.page-title{font-size:28px}a{text-decoration:none}textarea{border:0;font-size:12px;min-height:60px}.project-print{display:block}.lesson-glyph{display:none}.experiment-body{padding:15px}.experiment{border-color:#ccc}.journal-summary{background:white;border-color:#ccc}.fair-grid{grid-template-columns:repeat(4,1fr)}}

.site-links{display:flex;flex-wrap:wrap;gap:4px}.site-links a{display:inline-flex;align-items:center;min-height:44px;padding:8px 14px;border-radius:12px;font-weight:650;font-size:14px;text-decoration:none}.site-links a:hover{background:var(--mint)}.site-links a[aria-current="page"]{background:var(--ink);color:var(--white)}
@media(max-width:620px){.site-links{order:2;width:100%;gap:2px 14px}.site-links a{min-height:40px;padding:6px 2px;font-size:13px;text-decoration:underline;text-underline-offset:3px}.site-links a[aria-current="page"]{display:none}.top-controls{order:1}}
.grade-select{max-width:none}@media(max-width:620px){.grade-select{max-width:190px;font-size:12px}}

/* Readable shell and catalogue; activity logic and content are unchanged. */
@media screen{
  .topbar{justify-content:flex-end}
  .top-controls{flex-wrap:wrap}
  .grade-select{font-size:16px;min-height:44px}
  .lang-switch button{font-size:16px;min-height:44px;min-width:44px}
  .nav button{font-size:15px;min-height:44px;white-space:normal}
  .site-links{padding:16px 42px;border-top:1px solid var(--line)}
  .site-links a{min-height:44px;font-size:15px}
  .site-links a[aria-current="page"]{display:none}
  .eyebrow,.card-body .eyebrow,.side-label{font-size:13px;letter-spacing:0;text-transform:none}
  .brand-sub{font-size:11px;letter-spacing:0}
  .card-body p,.track p,.section-top p{font-size:14px}
  .card-open,.filter,.btn{font-size:14px;min-height:44px}
  .card-num,.card-time{font-size:12px;color:var(--ink)}
  .callout .btn.lime{color:var(--ink)}
  .lab-card:focus-within{outline:3px solid #5269d8;outline-offset:3px}
  :lang(hi) h1,:lang(hi) h2,:lang(hi) h3{letter-spacing:0;line-height:1.3}
}
@media screen and (max-width:860px){
  .nav{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));overflow:visible;gap:6px}
  .nav button{justify-content:center;padding:10px 8px}
  .site-links{padding:16px}
}
@media screen and (max-width:620px){
  .nav{grid-template-columns:repeat(2,minmax(0,1fr));margin-top:12px}
  .nav button{background:var(--paper)}
  .nav button.active{background:var(--ink)}
  .top-controls{justify-content:space-between;width:100%}
  .grade-select{max-width:100%;flex:1;min-width:170px}
  .lang-switch{flex-shrink:0}
  .lab-grid{grid-template-columns:1fr!important}
  .lab-card{display:grid;grid-template-columns:100px minmax(0,1fr)}
  .card-art{height:100%;min-height:150px}
  .card-art .art{max-width:90%;margin-top:16px}
  .card-num{display:none}
  .card-body{padding:18px 16px}
  .card-body .eyebrow{display:none}
  .card-body h3{font-size:19px;margin-top:0}
  .card-body p{font-size:14px}
  .catalog-head{flex-wrap:wrap}
}
@media print{.site-links{display:none}}
@media screen and (max-width:380px){.grade-select{flex-basis:100%;width:100%}.top-controls{justify-content:flex-end}}

/* Site links live at the top of the app again (owner, 8 Oct 2026): a teacher must always see the way back. */
@media screen{.topbar{justify-content:space-between}.topbar .site-links{padding:0;border:0;gap:2px}.topbar .site-links a{min-height:44px;padding:8px 12px;font-size:15px}}
@media screen and (max-width:620px){.topbar .site-links{order:0;width:100%;justify-content:flex-start;gap:4px 20px}.topbar .site-links a{padding:8px 0;font-size:15px;text-decoration:underline;text-underline-offset:3px}.top-controls{order:1}}
/* Calm screen design. Activity mechanics and print rules above remain independent. */
@media screen{
 :root{--paper:#fbfcf9;--white:#ffffff;--ink:#233d35;--muted:#52645a;--line:#dfe6e0;--lime:#dcebbf;--mint:#edf3ee;--blue:#edf2f7;--yellow:#f7f1df;--pink:#f7edef;--lilac:#f0edf6;--peach:#f6eee7;--focus:#315fbd;--body-size:20px;--radius:28px;--sans:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","Nirmala UI",Mangal,sans-serif;font-family:var(--sans);font-size:20px;color:var(--ink);background:var(--paper);color-scheme:light}
 .shell{display:block}.workspace{margin:0;width:100%}main{max-width:1120px;padding:32px 24px 48px;min-height:0}
 .route-context{max-width:1120px;margin:24px auto 0;padding:0 24px;font-size:16px;color:var(--muted)}
 h1,.page-title,.lesson-head h1{font-size:clamp(36px,4.5vw,56px);line-height:1.12;letter-spacing:-.035em;font-weight:650}
 h2,.section-top h2{font-size:32px;line-height:1.2;font-weight:650;letter-spacing:-.02em}
 h3,.guide-card h3,.reflection-panel h3,.experiment-heading h2,.case-card h3{font-size:25px;line-height:1.35;font-weight:650;letter-spacing:-.02em}
 main p,main li,main textarea,main select,main button,main label,
 main :is(.instruction,.feedback,.small-note,.control-label,.queue-empty,.model-output,.test-card,.test-card strong,.shape-example,.fair-card .prediction,.result-label,.slider-endpoints,.legend,.dataset-chip,.data-table,.data-table th,.bar-label,.bar-value,.vote-count,.case-counter,.save-row span,.page-subtitle,.source-list a,.mapping-table,.mapping-table th,.guide-policy){font-size:var(--body-size)!important;line-height:1.65}
 main button,main select,main input{min-height:44px}main button{min-width:44px}main textarea{min-height:150px}main textarea::placeholder{color:var(--muted)}
 main :is(.btn,.btn.small,.card-open,.back){min-height:48px;font-size:18px!important}
 main :is(.eyebrow),.lesson-top .pill:first-child,.lesson-glyph,.floating-label,.orbit-star,.orbit-dots,.hero-note,.welcome,.hero .pill,.hero-art:before,.hero-art:after,.card-art:before,.card-num,.callout-icon{display:none}
 .track .eyebrow{display:block;font-size:17px;letter-spacing:0}
 .hero{display:flex;flex-direction:column;align-items:center;min-height:0;padding:32px 24px 48px;border:0;background:none;text-align:center;overflow:visible;gap:0}
 .hero-copy{padding:0}.hero h1{font-size:clamp(42px,6vw,76px);max-width:780px;margin:0 auto 28px;font-weight:650;letter-spacing:-.045em}.hero h1 .serif{font:inherit}.hero p{max-width:52ch;margin:auto;color:var(--muted)}
 .hero-buttons{justify-content:center;margin-top:32px;gap:16px}.hero-buttons .btn.text{display:none}.hero-art{min-height:0;margin:32px auto 0;width:120px}.bibo-hero{width:120px;filter:none}
 .btn{border-radius:999px;padding:12px 24px;transform:none!important}.btn.secondary{background:var(--mint);border:0}.btn.lime{background:var(--mint);color:var(--ink)}
 .section-top{margin:48px 0 24px}.section-top p{margin-top:12px}.tracks{gap:24px}.track{padding:28px;border:1px solid transparent;border-radius:24px;background:var(--white)}.track.selected{background:var(--mint);border-color:#537862;box-shadow:none}.track h3{font-size:24px}.track-icon{border-radius:50%;background:var(--mint)}
 .filters{gap:12px;margin:24px 0 32px}.filter{font-size:18px;padding:10px 18px}.lab-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:28px}
 .lab-card{border:0;background:var(--white);border-radius:24px;display:flex;transform:none!important}.card-art{height:160px;background:none}.card-art .art{width:130px;height:110px}.card-time{font-size:16px;top:16px;right:20px;background:var(--paper);color:var(--muted)}.card-time svg{width:16px;height:16px}.card-body{padding:12px 28px 28px}.card-body h3{font-size:27px;margin:0 0 16px}.card-body p{margin-bottom:20px}
 .callout{background:var(--mint);color:var(--ink);padding:36px;border-radius:28px;margin-top:48px}.callout p{color:var(--muted)}.callout .btn{white-space:normal}
 .bottom-note{font-size:16px;line-height:1.7;margin-top:40px;padding-top:24px;display:block}.bottom-note span{display:block;margin-top:12px}.bottom-note button{font-size:16px!important;min-height:44px}
 .page-subtitle{margin:24px 0 36px;max-width:65ch}.back{margin-bottom:24px}.lesson-top{gap:16px;flex-wrap:wrap;margin-bottom:24px}.lesson-top .pill{font-size:17px;background:none;border:0;padding:0}.lesson-top .pill svg{width:18px;height:18px}.lesson-head{margin-bottom:32px}.lesson-head p{margin-top:20px;max-width:60ch}
 .concept{border:0;background:var(--mint);padding:28px;border-radius:24px;margin-bottom:40px}.concept>svg{color:var(--ink);margin-top:5px}
 .experiment{border:0;border-radius:28px;background:var(--white)}.experiment-heading{padding:28px 32px}.experiment-body{padding:32px}.split{grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:36px}.split>*{min-width:0}
 .inset,.case-card{border:0;background:var(--paper);padding:28px;border-radius:24px}.instruction{margin-bottom:24px}.feedback{padding:24px;margin-top:24px;color:var(--ink)}
 .reflection{grid-template-columns:1fr;gap:28px;margin-top:40px}.reflection-panel{padding:32px;border:0;border-radius:24px}.reflection-panel.offline{background:var(--mint)}.reflection-panel h3{margin-bottom:20px}.reflection-panel h3 svg{width:24px;height:24px}.save-row{flex-wrap:wrap;gap:16px}
 .directions{gap:12px}.direction{font-size:18px;padding:12px 8px}.queue-chip{min-height:44px;font-size:18px}.queue-empty{color:var(--muted)}.round-btn{width:44px;height:44px;flex-shrink:0}.vote-controls{gap:8px}.data-table th,.mapping-table th{letter-spacing:0;text-transform:none}.bar-label{white-space:normal;text-align:center;bottom:-54px;line-height:1.3}.bar-chart{margin-bottom:60px;padding-inline:0;gap:10px}
 .answer.text-answer{font-size:var(--body-size);flex-basis:100%;padding:16px 20px}.case-footer{flex-wrap:wrap;gap:20px}.case-icon{border-radius:50%;background:var(--mint)}
 .model-output{padding:24px}.slider-row input{height:44px;margin:0}.slider-row label{gap:16px}.slider-endpoints{gap:16px}.scatter text{font-size:13px;fill:var(--ink)}.scatter .axis-title{font-size:14px}.legend{flex-wrap:wrap;gap:12px}.dataset-chip{padding:6px 12px}.dataset-chip button{min-width:44px;min-height:44px}.test-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.test-card{padding:20px}.test-card strong{display:block}
 .fair-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.fair-card{padding:24px 16px}.result-label{padding:8px 12px}.fair-examples{padding:16px 0}.shape-example{padding:16px}.project-stages{gap:24px}.project-stage{padding:24px}.project-stage p{margin-top:16px}
 .journal-summary{background:var(--mint);border:0;padding:28px}.journal-summary h3{font-size:25px}.journal-list{gap:24px}.journal-item{border:0;padding:28px}.journal-item h3{font-size:25px}.journal-item time{font-size:16px}.empty-state{padding:48px 24px;border:0;background:var(--mint)}.empty-state p{max-width:48ch}
 .guide-grid{grid-template-columns:1fr;gap:28px}.guide-card{padding:32px;border:0}.mapping-table{min-width:560px}.guide-wide{grid-column:auto}.source-list{gap:20px}.wide-actions{gap:16px;flex-wrap:wrap}
 .next-step{max-width:1072px;margin:0 auto 48px;padding:32px;border-radius:28px;background:var(--mint)}.next-step h2{font-size:28px}.next-step p{font-size:20px;margin:16px 0 24px}.next-step .btn{font-size:18px;min-height:48px}.next-step .wide-actions{margin:0}.next-step svg{width:20px}
 #toast{font-size:18px;line-height:1.6;box-shadow:none}.storage-notice{font-size:18px;line-height:1.7}
 :lang(hi){--body-size:21px}:lang(hi) h1,:lang(hi) h2,:lang(hi) h3{letter-spacing:0;line-height:1.4}:lang(hi) main :is(p,li,textarea,button,label,.feedback,.small-note,.instruction,.model-output,.test-card){line-height:1.85}
}
@media screen and (max-width:760px){
 :root{--body-size:18px;font-size:18px}:lang(hi){--body-size:19px}main{padding:24px 16px 40px}.route-context{margin-top:20px;padding:0 16px;font-size:16px}
 h1,.page-title,.lesson-head h1{font-size:36px}h2,.section-top h2{font-size:28px}h3,.guide-card h3,.reflection-panel h3,.experiment-heading h2{font-size:24px}
 .hero{padding:16px 0 32px}.hero h1{font-size:44px;letter-spacing:-.035em;line-height:1.15;margin-bottom:24px}.hero-art,.bibo-hero{width:96px}.hero-art{margin-top:24px}.hero-buttons{margin-top:24px}.hero p{max-width:35ch}
 .tracks,.lab-grid{grid-template-columns:1fr!important}.track{padding:24px 20px}.track h3{font-size:23px}.track-icon{display:none}.track .arrow{width:24px}.lab-card{display:flex}.card-art{height:130px;min-height:0}.card-body{padding:12px 24px 24px}.card-body h3{font-size:26px}.catalog-head{flex-wrap:wrap}
 .concept{padding:24px 20px;gap:12px}.concept>svg{display:none}.experiment-heading,.experiment-body{padding:24px 20px}.experiment-heading h2{font-size:24px}.split,.project-stages{grid-template-columns:1fr;gap:32px}.inset,.case-card{padding:24px 16px}.directions{grid-template-columns:repeat(2,1fr)}.robot-grid{max-width:360px}.sequence{gap:8px}.sequence-item{width:44px;height:56px}.test-grid,.fair-grid{grid-template-columns:1fr}.bar-chart{gap:8px}
 .reflection-panel,.guide-card,.journal-item{padding:24px 20px}.journal-item header{align-items:flex-start}.journal-summary{padding:24px 20px}.journal-summary>svg{display:none}.next-step{margin:0 16px 40px;padding:24px 20px}.next-step p{font-size:18px}:lang(hi) .next-step p{font-size:19px;line-height:1.85}.next-step .btn{text-align:left;justify-content:flex-start}.callout{padding:28px 24px}.save-row{display:block}.save-row span{display:block;margin-top:12px}.reflection-panel textarea{min-height:180px}
}
@media print{.route-context,.next-step,.site-header{display:none!important}}
/* Shared header contract: keep this block identical in app, site and self-contained packs. */
.site-header{background:var(--white);border-bottom:1px solid var(--line);color:var(--ink);font-family:var(--sans)}
.site-header .wrap{width:min(1160px,100% - 40px);margin:auto;display:flex;align-items:center;flex-wrap:wrap;gap:12px;padding-block:14px;position:relative}
.site-header .brand{display:inline-flex;align-items:center;gap:8px;min-height:44px;font-size:23px;font-weight:750;letter-spacing:-1px;text-decoration:none;margin-right:auto;white-space:nowrap}
.site-header .brand-mark,.site-header .mark{display:grid;place-items:center;width:34px;height:34px;padding:6px;border-radius:50%;background:var(--mint)}
.site-header .brand svg{width:22px;height:22px}
.site-header .four{color:var(--ink)}
.site-header .desktop-links{display:flex;gap:20px;margin-right:24px}
.site-header .desktop-links [aria-current="page"]{text-decoration:underline;text-underline-offset:6px}
.site-header .desktop-links a{display:inline-flex;align-items:center;min-height:44px;text-decoration:none;font-size:16px;font-weight:600}
.site-header .lang,.site-header .lang-switch{display:flex;gap:0;padding:0;background:none;border:0;box-shadow:none;margin:0}
.site-header .lang [aria-current],.site-header .lang-switch .active{display:none}
.site-header .lang a,.site-header .lang-switch button{display:inline-flex;justify-content:center;align-items:center;min-height:44px;min-width:44px;padding:8px;border:0;background:none;color:var(--ink);font-size:16px;font-weight:650;text-decoration:none;border-radius:12px;cursor:pointer}
.site-menu{font-size:16px}
.site-menu summary{display:flex;align-items:center;justify-content:center;min-height:44px;padding:8px 18px;border-radius:999px;background:var(--ink);color:var(--white);font-weight:650;cursor:pointer;list-style:none}
.site-menu summary::-webkit-details-marker{display:none}
.site-menu summary::after{content:'+';margin-left:10px;font-size:20px;font-weight:400}
.site-menu[open] summary::after{content:'−'}
.site-menu .menu-panel{position:absolute;top:100%;left:0;right:0;background:var(--white);border:1px solid var(--line);border-radius:0 0 24px 24px;padding:24px;z-index:30;box-shadow:0 12px 24px #203d3610}
.site-menu nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;margin:0}
.site-menu nav a,.site-menu nav button{display:flex;align-items:center;min-height:48px;padding:10px 14px;border:0;border-radius:12px;background:none;color:var(--ink);font:inherit;text-align:left;text-decoration:none;white-space:normal}
.site-menu nav [aria-current="page"]{display:flex;background:var(--mint);color:var(--ink);font-weight:700}
.site-menu nav a:hover,.site-menu nav button:hover{background:var(--paper)}
.site-menu nav svg{display:none}
.site-menu .nav{border-top:1px solid var(--line);margin-top:16px;padding-top:16px}
.menu-settings{display:flex;align-items:center;gap:16px;margin-top:20px;padding-top:20px;border-top:1px solid var(--line)}
.menu-settings label{font-size:16px;font-weight:650}
.menu-settings select{min-height:48px;max-width:100%;padding:10px;border:1px solid var(--line);border-radius:12px;background:var(--white);color:var(--ink);font-size:16px}
.site-header a:focus-visible,.site-header button:focus-visible,.site-header summary:focus-visible,.site-header select:focus-visible{outline:3px solid var(--focus);outline-offset:4px}
@media(max-width:760px){
 .site-header .wrap{width:calc(100% - 32px);gap:8px;padding-block:8px}
 .site-header .brand{font-size:21px;gap:6px}
 .site-header .brand-mark,.site-header .mark{display:none}
 .site-header .desktop-links{display:none}
 .site-menu summary{padding:8px 14px}
 .site-menu summary::after{margin-left:6px}
 .site-menu .menu-panel{padding:16px;max-height:75vh;overflow:auto}
 .site-menu nav{grid-template-columns:1fr 1fr}
 .menu-settings{display:block}.menu-settings label{display:block;margin-bottom:8px}.menu-settings select{width:100%}
}
@media print{.site-header{display:none!important}}
/* End shared header contract. */
.skip-link:not(:focus){clip-path:inset(50%);width:1px;height:1px;overflow:hidden}
@media screen{
 .card-body h2{font-size:27px;margin:0 0 16px;line-height:1.35}
 .journal-summary h2,.journal-item h2,.empty-state h2{font-size:25px;line-height:1.35}
 .empty-state h2{margin-bottom:16px}.guide-card h2{font-size:25px;display:flex;gap:10px;align-items:center;margin-bottom:20px}.guide-card h2 svg{width:24px;height:24px;flex-shrink:0}
}
@media print{.guide-card h2{font-size:17px;display:flex;gap:10px;align-items:center;margin-bottom:16px}.guide-card h2 svg{width:23px;height:23px}}

/* UI v3 screen system. Keep print typography and palette unchanged. */
@media screen{
 @font-face{font-family:"Baloo 2";font-style:normal;font-weight:700;font-display:swap;src:url("/assets/fonts/baloo2-headings.woff2") format("woff2")}
 :root{--heading:"Baloo 2",var(--sans);--paper:#fffdf8;--ink:#263c36;--muted:#53635d;--line:#dedfd5;--mint:#eef3e8;--radius:28px;--shadow:0 8px 24px #263c360b;--motion-fast:160ms;--motion-enter:320ms;--accent:#356145;--texture:none}
 [data-band="foundation"]{--paper:#fffcf3;--ink:#2d4032;--muted:#53624d;--mint:#edf3df;--lime:#f4dc76;--blue:#e5f2f7;--yellow:#fff0bd;--pink:#fce7df;--accent:#38663d;--line:#dcdcca;--texture:radial-gradient(#e4dfcf .9px,transparent .9px);--texture-size:22px 22px}
 [data-band="explorer"]{--paper:#f7f8ff;--ink:#2d3055;--muted:#565d77;--mint:#edf0fc;--lime:#d4ddfb;--blue:#e5f2f5;--yellow:#faf0d7;--pink:#f1eafa;--accent:#3c4c92;--line:#dbdeed;--texture:linear-gradient(#e3e6f2 1px,transparent 1px),linear-gradient(90deg,#e3e6f2 1px,transparent 1px);--texture-size:28px 28px}
 h1,h2,h3,.page-title,.lesson-head h1,.hero h1,.card-body h2{font-family:var(--heading);font-weight:700;letter-spacing:-.015em}
 :lang(hi) :is(h1,h2,h3,.page-title){letter-spacing:0;line-height:1.4}
 .band-world{background-color:var(--paper);background-image:var(--texture);background-size:var(--texture-size);color:var(--ink);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
}
@media screen{
 html[data-band] body{background-color:var(--paper);background-image:var(--texture);background-size:var(--texture-size)}
 .lab-card,.experiment,.guide-card,.journal-item{box-shadow:var(--shadow)}
 .card-art{border-radius:24px 24px 0 0;background:var(--mint)}
 .card-art .art{width:150px;height:125px}
 .btn.primary{background:var(--ink);color:var(--white)}
}

@keyframes pageFadeSlide {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes gridFade {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes successPop {
  0% { transform: scale(1); }
  50% { transform: scale(1.02); }
  100% { transform: scale(1); }
}
.page-fade { animation: pageFadeSlide 0.3s ease-out; }
.grid-fade .lab-grid { animation: gridFade 0.4s ease-out; }
.success-pop { animation: successPop 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275); }

/* Band Switch Styles */
.band-switch {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 16px;
  background: var(--mint);
  padding: 16px 20px;
  border-radius: 12px;
  margin-bottom: 24px;
}
.band-switch span {
  font-weight: 650;
  font-size: 17px;
}
.band-options {
  display: flex;
  gap: 8px;
}
.band-options button {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 8px 16px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
}
.band-options button.active {
  background: var(--ink);
  color: var(--white);
  border-color: var(--ink);
}

/* Numbered path styles */
.on-path {
  position: relative;
}
.card-num {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--white);
  color: var(--ink);
  width: 34px;
  height: 34px;
  border-radius: 17px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 17px;
  box-shadow: 0 1px 3px rgba(0,0,0,.12);
  z-index: 2;
}
.start-hint {
  position: absolute;
  top: 12px;
  left: 54px;
  background: var(--ink);
  color: var(--white);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.3;
  padding: 7px 12px;
  border-radius: 999px;
  z-index: 3;
}
.link-pill {
  cursor: pointer;
  text-decoration: none;
  color: inherit;
}
.link-pill:hover {
  background: var(--line);
}