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button{color:#fff;background:#17211f;border-radius:8px;flex:none;align-items:center;gap:7px;min-height:38px;padding:8px 11px;font-weight:850;display:inline-flex}.side-picker,.reflection-pickers{gap:14px;display:grid}.side-picker>div>span,.reflection-pickers>div>span{text-transform:uppercase;margin-bottom:8px;font-size:.8rem;font-weight:900;display:block}.equation-bridge{grid-template-columns:minmax(260px,1fr) minmax(180px,.75fr);gap:18px}.bridge-equation{color:#fff;background:#17211f;border-radius:8px;align-content:center;gap:10px;padding:18px;display:grid}.bridge-equation span{color:#aee3d7;text-transform:uppercase;font-size:.78rem;font-weight:900}.bridge-equation strong{font-size:clamp(1.05rem,2vw,1.45rem);line-height:1.25}.root-entry{grid-template-columns:1fr 1fr;gap:12px;display:grid}.root-entry label{color:var(--muted);text-transform:uppercase;gap:8px;font-size:.8rem;font-weight:900;display:grid}.root-entry input{border:1px solid var(--line);color:var(--ink);background:#fff;border-radius:8px;min-width:0;padding:12px;font-size:1.25rem;font-weight:850}.zero-product{grid-template-columns:1fr 1fr;gap:14px}.zero-product div{color:#fff;text-align:center;background:#17211f;border-radius:8px;align-content:center;gap:12px;min-height:240px;padding:18px;display:grid}.zero-product span{color:#aee3d7;font-size:1.1rem;font-weight:900}.zero-product strong{font-size:clamp(2rem,5vw,4rem);line-height:1}.primary-action{color:#fff;background:#17211f;border-radius:8px;justify-content:center;gap:8px;min-height:46px;padding:10px 14px;font-weight:850}.substitute-visual{gap:18px;display:grid}.substitute-equation{color:#fff;text-align:center;background:#17211f;border-radius:8px;padding:18px;font-size:clamp(1.1rem,2.6vw,2rem);font-weight:900;line-height:1.2}.cancel-balance{grid-template-columns:1fr auto 1fr;align-items:stretch;gap:12px;display:grid}.cancel-balance>div:not(.equals-zero){border:1px solid var(--line);background:#f8fbfa;border-radius:8px;gap:10px;padding:12px;display:grid}.cancel-balance strong{text-align:center}.balance-stack{grid-template-columns:repeat(4,1fr);gap:5px;display:grid}.balance-stack span{border-radius:5px;height:28px}.balance-stack.positive span{background:var(--gold);border:1px solid #d8bd5b}.balance-stack.negative span{background:var(--tile-negative);border:1px solid #d88a82}.equals-zero{color:var(--accent-strong);align-self:center;font-weight:900}.complete-square-visual{grid-template-columns:minmax(260px,1fr) minmax(180px,.55fr);align-items:center;gap:18px;display:grid}.square-build{grid-template-rows:minmax(130px,1fr) minmax(110px,.85fr);grid-template-columns:minmax(120px,1fr) minmax(110px,.85fr);gap:8px;display:grid}.square-main,.square-strip,.corner-grid{border:2px solid 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p{color:#d7e3df;margin:0;line-height:1.48}.sea-info-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;display:grid}.sea-panel{align-content:start;gap:10px;min-height:210px;padding:16px;display:grid}.sea-panel>span{color:var(--muted)}.sea-panel strong{color:var(--ink);font-size:clamp(1.18rem,2vw,1.7rem);line-height:1.12}.sea-panel p{color:var(--muted);margin:0;line-height:1.5}.sea-panel.dark{color:#fff;background:#17211f}.sea-panel.dark>span{color:#aee3d7}.sea-panel.dark strong{color:#fff}.sea-panel.dark p{color:#d7e3df}.sea-panel.wide{grid-column:span 1}.sea-rule-stack{gap:8px;display:grid}.sea-rule-stack code{border:1px solid var(--line);color:#235d6d;overflow-wrap:anywhere;background:#f8fbfa;border-radius:8px;padding:10px;font-family:SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:.86rem;font-weight:800}.import-pack-page{background:linear-gradient(135deg, #f7faf9 0%, #dff1f4 50%, #fff8df 100%), 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