*{box-sizing:border-box}:root{--ink:#202940;--muted:#6c758b;--line:#e2e6ef;--purple:#6659df;--purple-dark:#493cc2;--coral:#ff725f;--mint:#16ad84;--amber:#f4a43b;--panel:#fff;--shadow:0 22px 60px rgba(37,45,78,.11)}html,body{width:100%;height:100%;margin:0;overflow:hidden}body{font-family:"DM Sans",sans-serif;color:var(--ink);background:#edf0f7}button,input,select{font:inherit;color:inherit}.app-shell{width:100vw;height:100vh;display:grid;grid-template-rows:68px minmax(0,1fr);background:radial-gradient(circle at 9% 4%,#fff 0,transparent 31%),radial-gradient(circle at 91% 95%,rgba(102,89,223,.09),transparent 35%),linear-gradient(135deg,#f7f8fc,#eceff6)}.topbar{display:flex;align-items:center;justify-content:space-between;padding:0 24px;background:rgba(255,255,255,.91);border-bottom:1px solid 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360px;gap:14px;padding:14px}.visual-panel,.control-panel{min-height:0;border-radius:22px;background:var(--panel);border:1px solid rgba(87,99,132,.12);box-shadow:var(--shadow)}.visual-panel{overflow:hidden;display:grid;grid-template-rows:auto auto minmax(0,1fr) auto auto;gap:10px;padding:22px;background:linear-gradient(145deg,#fff,#fbfbfe)}.panel-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:18px}.panel-heading h2{font:800 clamp(18px,2.1vw,29px)/1.18 Manrope,sans-serif;letter-spacing:-.025em;margin:5px 0 0}.direction-badge{display:flex;align-items:center;gap:7px;background:#efefff;color:var(--purple-dark);border-radius:99px;padding:8px 11px;font-size:11px;font-weight:800;white-space:nowrap}.direction-badge span{font-size:18px;line-height:.5}.equation-strip{justify-self:center;display:flex;align-items:center;gap:18px;padding:10px 22px;border:1px solid #e7e9f2;border-radius:15px;background:#fff;box-shadow:0 10px 28px rgba(50,57,90,.08);font:800 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@media(min-width:761px) and (max-height:710px){.app-shell{grid-template-rows:56px minmax(0,1fr)}.topbar{padding:0 17px}.brand-mark{width:34px;height:34px;font-size:20px}.brand h1{font-size:17px}.workspace{gap:8px;padding:8px}.visual-panel{gap:6px;padding:13px}.panel-heading h2{font-size:19px}.equation-strip{padding:6px 17px;font-size:21px}.number-line-card svg{min-height:145px}.line-key{padding:4px}.reasoning-row{grid-template-columns:1fr 1fr 1.15fr}.notice-card{grid-column:auto}.step-card,.notice-card{min-height:44px;padding:6px 8px}.test-row{padding:7px 10px}.control-head{padding:9px 14px}.solution-count{width:44px;height:44px}.presets{padding:7px 12px}.slider-controls{padding:7px 14px 4px}.slider-controls label+input{margin:1px 0 3px}.relation-control{padding:6px 14px}.relation-control>span{margin-bottom:3px}#relationButtons button{height:29px}.challenge-card{margin:6px 10px 8px;padding:7px 9px}.answer-row{margin-top:5px}.challenge-card p{margin-top:4px}}
@media(max-width:760px){.app-shell{grid-template-rows:55px minmax(0,1fr)}.topbar{padding:0 10px}.brand{gap:8px}.brand-mark{width:33px;height:33px;font-size:19px}.brand p,.year-pill{display:none}.brand h1{font-size:15px}.quiet-button{padding:7px 9px;font-size:10px}.workspace{grid-template-columns:1fr;grid-template-rows:minmax(0,55%) minmax(0,45%);padding:6px;gap:6px}.visual-panel,.control-panel{border-radius:16px}.visual-panel{gap:4px;padding:9px;grid-template-rows:auto auto minmax(0,1fr) auto auto}.panel-heading h2{font-size:13px;margin-top:2px}.kicker{font-size:7px}.direction-badge{font-size:8px;padding:5px 7px}.direction-badge span{font-size:13px}.equation-strip{padding:5px 10px;gap:8px;font-size:17px;border-radius:10px}.number-line-card{border-radius:11px}#numberLine{min-height:105px}.line-key{display:none}.reasoning-row{grid-template-columns:1fr 1fr;gap:4px}.step-card{min-height:36px;padding:4px 6px;gap:5px}.step-card>span{width:19px;height:19px;flex-basis:19px;font-size:7px}.step-card small{font-size:6px}.step-card strong{font-size:9px}.notice-card{display:none}.test-row{grid-template-columns:72px 1fr 112px;gap:6px;padding:5px 7px;border-radius:9px}.test-row label span{display:none}.test-row label strong{font-size:10px}.test-result{font-size:7px}.control-panel{display:grid;grid-template-columns:1fr 1fr;grid-template-rows:auto auto minmax(0,1fr) auto}.control-head{grid-column:1/-1;padding:6px 10px}.control-head>div:first-child span{display:none}.control-head h2{font-size:12px;margin:0}.solution-count{width:auto;height:auto;display:flex;gap:4px;border:0}.solution-count strong{font-size:12px}.solution-count span{font-size:6px;align-self:center}.presets{grid-column:1/-1;padding:5px 8px;gap:4px}.presets button{padding:4px;font-size:7px}.slider-controls{padding:5px 8px;border-right:1px solid #eceef4}.slider-controls label{font-size:7px}.slider-controls label+input{margin:0 0 2px;height:12px}.slider-controls output{min-width:20px;padding:1px 4px}.relation-control{padding:5px 7px}.relation-control>span{font-size:6px;margin-bottom:3px}#relationButtons{gap:3px}#relationButtons button{height:26px;font-size:12px}.challenge-card{grid-column:1/-1;margin:0;padding:5px 8px;border-radius:0;border-width:1px 0 0}.challenge-top span{font-size:6px}.challenge-top h3{font-size:9px}.challenge-top button{padding:4px 6px;font-size:6px}.answer-row{grid-template-columns:auto 40px 1fr 50px;margin-top:4px}.answer-row label,.challenge-card p{font-size:6px}.answer-row select,.answer-row input,.answer-row button{height:25px;font-size:7px}.challenge-card p{min-height:10px;margin:3px 0 0}}
@media(max-width:410px){.workspace{grid-template-rows:minmax(0,52%) minmax(0,48%)}.panel-heading h2{font-size:11px}.direction-badge{display:none}.equation-strip{font-size:15px}.test-row{grid-template-columns:58px 1fr 98px}.challenge-card p{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}}
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