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#d5e1eb;border-radius:9px;background:#fbfdff}.problem-spec span,.example-box>span{display:block;margin-bottom:5px;color:#8d6800;font-size:9px;font-weight:900;letter-spacing:.08em}.problem-spec p{margin:0;color:#506c83;font-size:12px;line-height:1.5}.constraints{margin:14px 0 0;padding:12px 14px;border-left:3px solid var(--cyan);background:#eef9fb;color:#466a77;font-size:11px;line-height:1.55}.example-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:14px}.example-box{min-width:0}.example-box pre{min-height:58px;margin:0;padding:12px;overflow:auto;border-radius:8px;background:#071827;color:#d8ecfa;font:11px/1.55 monospace;white-space:pre-wrap}.problem-actions-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}.problem-actions-row button,.problem-actions-row a{min-height:38px;padding:8px 11px;border:1px solid #a7c0d4;border-radius:8px;background:white;color:#174f7d;font-size:10px;font-weight:900;cursor:pointer;text-decoration:none}.problem-actions-row .primary-tool{border-color:#1469b3;background:#1469b3;color:white}.reveal-panel{margin-top:10px;padding:14px;border:1px solid #cbdce9;border-radius:9px;background:#f4f9fd;color:#45637b;font-size:12px;line-height:1.6}.reveal-panel[hidden]{display:none}.reveal-panel strong{color:#0b4e82}.solution-head{display:flex;justify-content:space-between;gap:10px;margin-bottom:8px}.solution-head button{border:0;background:none;color:#1167ab;font-weight:900;cursor:pointer}.reveal-panel pre{margin:8px 0 0;padding:14px;overflow:auto;border-radius:8px;background:#061725;color:#ddecf8;font:11px/1.55 monospace}.workbench{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(220px,.6fr);gap:10px;margin-top:11px}.workbench[hidden]{display:none}.workspace-box,.calculator-box{min-width:0;border:1px solid #c4d7e6;border-radius:10px;background:#f8fbfe}.tool-head{display:flex;align-items:center;justify-content:space-between;padding:9px 11px;border-bottom:1px solid 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@media(max-width:1000px){.practice-hero{grid-template-columns:1fr}.arena-layout{grid-template-columns:1fr}.arena-guide{position:static}.workbench{grid-template-columns:1fr}}
@media(max-width:700px){.practice-main{padding:18px 10px 40px}.practice-hero{padding:24px 18px;border-radius:15px}.practice-hero h1{font-size:38px}.arena-toolbar{grid-template-columns:1fr}.arena-toolbar>div{padding-left:0}.arena-layout{margin-top:12px}.arena-guide{display:none}.problem-head{flex-wrap:wrap;padding:15px}.problem-title{order:2;flex-basis:calc(100% - 62px)}.difficulty{margin-left:auto}.solve-toggle{order:3;width:100%}.problem-body{padding:16px}.problem-spec,.example-grid{grid-template-columns:1fr}.problem-actions-row>*{flex:1 1 calc(50% - 8px);text-align:center}.workspace-editor{height:260px}.level-strip{border-radius:10px}}