:root{--color-bg:#0f1117;--color-bg-secondary:#1a1d27;--color-bg-card:#1e2130;--color-bg-hover:#252838;--color-border:#2a2d3a;--color-text:#e4e6ed;--color-text-secondary:#9295a5;--color-text-dim:#6b6e80;--color-primary:#6c8cff;--color-primary-hover:#5a7af0;--color-success:#4ade80;--color-warning:#fbbf24;--color-danger:#f87171;--color-easy:#4ade80;--color-medium:#fbbf24;--color-hard:#f87171;--sidebar-width:300px;--header-height:56px;--radius:8px;--radius-sm:4px;--font-mono:"SF Mono","Fira Code",monospace}*{box-sizing:border-box;margin:0;padding:0}body,html{background:var(--color-bg);color:var(--color-text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;line-height:1.6;overflow:hidden}#__nuxt,body,html{height:100%}a{color:var(--color-primary);text-decoration:none}a:hover{text-decoration:underline}.app-layout,.sidebar{display:flex;height:100vh;overflow:hidden}.sidebar{background:var(--color-bg-secondary);border-right:1px solid 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h3{color:var(--color-primary);font-size:18px;font-weight:600;margin:24px 0 12px}.theory-content h3:first-child{margin-top:0}.theory-content h4{font-size:15px;font-weight:600;margin:16px 0 8px}.theory-content p{margin-bottom:12px}.theory-content ol,.theory-content ul{margin:8px 0 12px 20px}.theory-content li{margin-bottom:4px}.definition-box{background:#6c8cff14;border-left:3px solid var(--color-primary)}.definition-box,.example-box{border-radius:0 var(--radius) var(--radius) 0;margin:16px 0;padding:16px 20px}.example-box{background:#4ade800f;border-left:3px solid var(--color-success)}.warning-box{background:#fbbf240f;border-left:3px solid var(--color-warning);border-radius:0 var(--radius) var(--radius) 0;margin:16px 0;padding:16px 20px}.exercise-card{background:var(--color-bg-card);border:1px solid var(--color-border);border-radius:var(--radius);margin-bottom:12px;overflow:hidden}.exercise-header{align-items:center;cursor:pointer;display:flex;justify-content:space-between;padding:12px 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