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#21343d14}.course-tabs{width:min(1180px,100%);margin:0 auto 14px;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.course-tab{min-height:54px;border:1px solid rgba(34,49,61,.14);border-radius:8px;background:#ffffffa8;color:#263746;display:grid;justify-items:center;align-content:center;padding:12px 16px;text-align:center}.course-tab span{font-weight:850}.course-tab--active{background:#1f6f69;color:#fff;border-color:#1f6f69}.course-frame{width:min(1180px,100%);margin:0 auto;border:1px solid rgba(35,61,74,.14);border-radius:8px;background:#ffffffc7;box-shadow:0 28px 70px #1f3a4721;padding:20px;display:grid;gap:18px}.course-heading{display:grid;gap:6px}.course-heading h2{font-size:clamp(1.45rem,3vw,2.2rem);color:#1d303c}.workspace{display:grid;grid-template-columns:minmax(420px,1fr) minmax(320px,420px);gap:18px;align-items:stretch}.stage,.control-panel{border:1px solid 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span{color:#ffffffc7;font-weight:800}@media (max-width: 920px){.lab-shell{padding:18px}.workspace,.course-tabs{grid-template-columns:1fr}.hero__copy{min-height:auto;padding:8px 0}.stage{min-height:420px}}@media (max-width: 560px){.course-frame{padding:12px}.stage{min-height:390px;padding:16px}.metric-grid,.formula-picker,.layout-picker,.dimension-editor,.base-view-controls{grid-template-columns:1fr}.base-prism-svg{min-height:330px}}