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@media(max-width:920px){.workspace-grid{grid-template-columns:minmax(0,1fr)}.workspace-side{display:grid;grid-template-columns:1fr 1fr;gap:13px}.workspace-side .side-card{margin-bottom:0}.workspace-side .side-card:last-of-type{grid-column:1/-1}.graph-wrap{max-height:240px}.sidebar{width:207px}.chapter-seal{display:none}.topbar{padding:0 22px}.top-actions{gap:14px}.chapter-grid{grid-template-columns:repeat(2,1fr)}}
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.formula-button:disabled{opacity:1;color:inherit;cursor:default}
.derived-toggle{display:flex;align-items:center;justify-content:space-between;gap:12px;border:1px solid #dce7d5;border-radius:6px;padding:10px 11px;background:#f3f7ee;margin:0 0 17px;cursor:pointer}.derived-toggle strong{display:block;font-size:10px;font-weight:650;color:#47623d}.derived-toggle small{display:block;font-size:9px;color:#87957b;margin-top:3px}.derived-toggle input{accent-color:var(--green);width:17px;height:17px;flex-shrink:0;cursor:pointer}.rule-group-label{font-size:9px;font-weight:650;color:#657b58;letter-spacing:.45px;margin:10px 0 8px}.derived-group-label{margin-top:17px;padding-top:13px;border-top:1px solid #e6ecdf;display:flex;align-items:center;justify-content:space-between;gap:7px}.derived-group-label span{font-size:8px;color:#94a185;font-weight:400;letter-spacing:0}.rule-chip:disabled{opacity:.4;cursor:not-allowed}.side-card .derived-scope-note{font-size:9px;line-height:1.6;margin:11px 0 0}.field optgroup{font-weight:650;color:#526b45}.field option{font-weight:400;color:#42563b}.field optgroup:disabled,.field option:disabled{color:#a4af9b}

.textbook-link{display:inline-block;font-size:11px;font-weight:600;text-underline-offset:3px;white-space:nowrap}.side-heading .textbook-link{margin-top:12px}.breadcrumb{flex-wrap:wrap}.breadcrumb>span:first-child{flex:1;min-width:180px}

.course-byline{font-size:11px;color:var(--muted);margin-top:4px}