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@media(max-width:1000px){.welcome-line{gap:10px}.welcome-line .grade-selector{width:100%}.grade-choice{min-height:52px}}
@media(max-width:700px){.shell{padding:14px 16px 88px}.topbar{height:64px}.welcome-line{margin-bottom:12px}.hero{padding:18px 20px;grid-template-columns:1fr}.hero-art{display:none}.hero h1{margin-bottom:10px}.hero p{margin-bottom:10px}.hero .primary{min-height:48px;padding:10px 18px}.summary-strip{padding:9px 5px;margin-bottom:14px}.topic-card{min-height:148px;padding:13px}.topic-card h3{margin-top:10px}.section-heading{margin:14px 0 10px}.topic-grid{gap:10px}.lesson-body{padding:18px}.lesson-head{margin-bottom:12px}.illustration{min-height:64px;margin-bottom:12px}.lesson-actions{gap:10px}.question{padding:20px}.question h2{margin:10px 0 16px}.quiz-controls{margin-top:16px}.stats{gap:8px;margin:14px 0}.stats article{padding:12px 6px}.report-row{padding:10px 0}.panel{padding:18px}.profile-form{padding:18px;margin:6px auto}.profile-form .grade-choice{min-height:60px}.badge{padding:16px 10px}.footer{padding-top:12px;margin-top:12px}.lab-stage{padding:12px}.cycle button{min-height:76px;padding:10px 6px}.mobile-nav{height:68px}.circuit{height:200px}.extras{margin-top:14px;padding:10px 14px}}

.lesson-sections{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:7px;margin-bottom:18px}.lesson-sections button{min-height:48px;border:2px solid var(--line);border-radius:12px;padding:8px;background:#fff;font-weight:800}.lesson-sections button.active{background:var(--mint);border-color:var(--deep);box-shadow:0 3px 0 var(--deep)}.lesson-section{min-height:250px}.lesson-section>.eyebrow{margin-bottom:10px}.section-controls{display:flex;justify-content:space-between;gap:12px;margin-top:16px}.answer-reveal{background:var(--mint);padding:12px 16px;border-radius:14px;margin:14px 0}.answer-reveal summary{cursor:pointer;font-weight:800;min-height:32px;align-content:center}.answer-reveal p{margin:12px 0 0}.lesson-actions{border-top:1px solid var(--line);padding-top:14px}.lesson-actions .text-button{margin-left:auto}@media(max-width:800px){.lesson-sections{grid-template-columns:repeat(2,minmax(0,1fr))}.lesson-section{min-height:0}}@media print{.lesson-sections,.section-controls,.lesson-actions{display:none!important}.lesson-section{min-height:0}.print-only h2{margin-top:24px}.print-only details,.lesson-section details{break-inside:avoid}.lesson-body .print-only{display:block!important}}

@media print{.lesson-section{display:none!important}}

.lesson-pagination{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:14px}.lesson-pagination span{text-align:center;font-weight:800}.lesson-pagination .secondary{padding:10px 14px}@media(max-width:500px){.lesson-pagination{flex-wrap:wrap}.lesson-pagination span{order:-1;width:100%}.lesson-pagination .secondary{flex:1}}

.investigation-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.investigation-grid .lab-card{padding:22px}.investigation-grid .section-heading{margin:12px 0}.investigation-grid .lab-card small{font-weight:800;color:var(--deep)}.lab-card-status{margin:15px 0 0!important}.lab-workbench{max-width:1050px;margin:auto}.lab-steps{grid-template-columns:repeat(3,minmax(0,1fr))}.lab-plan{max-width:850px}.lab-workbench p{line-height:1.65}.lab-prediction{height:88px}.lab-oral-row{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-top:10px}.lab-factors{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:18px 0}.lab-factors fieldset{border:1px solid var(--line);border-radius:15px;padding:15px;margin:0;min-width:0}.lab-factors legend{font-weight:800;padding:0 5px}.lab-factors fieldset>div{display:flex;gap:8px;flex-wrap:wrap}.lab-factors button{min-height:48px}.lab-factors button.active{background:var(--mint);border:2px solid var(--deep)}.model-result{display:flex;align-items:center;gap:18px;background:var(--mint);padding:20px;border-radius:18px;margin-top:18px;border:1px solid var(--line)}.model-result p{margin:0}.model-icon{font-size:54px;min-width:65px;text-align:center}.trial-heading{display:flex;align-items:center;justify-content:space-between;gap:15px;margin-top:20px}.trial-heading h3{margin:0}.trial-table-wrap{overflow:auto;margin:12px 0}.trial-table{border-collapse:collapse;width:100%;text-align:left}.trial-table th,.trial-table td{padding:11px 12px;border:1px solid var(--line);vertical-align:top}.trial-table th{background:var(--mint)}.investigation-report{margin-top:20px}.lab-workbench .section-controls{border-top:1px solid var(--line);padding-top:16px}@media(max-width:800px){.investigation-grid{grid-template-columns:1fr}.investigation-grid .lab-card{padding:18px}.investigation-grid .lab-card>span{font-size:38px}.lab-factors{grid-template-columns:1fr}.model-result{align-items:flex-start;padding:16px;gap:10px}.model-icon{font-size:38px;min-width:42px}.trial-heading{flex-wrap:wrap}.lab-steps{gap:6px}.lab-steps button{padding:8px 6px}.trial-table th,.trial-table td{padding:8px}.lab-workbench{padding:18px}}