:root{color-scheme:light;--bg-color: #FFFFFF;--card: #FFFFFF;--surface-2: #ffffff;--surface-3: #f8f3f3;--ink: #463A4F;--ink-2: #6D5B7B;--ink-3: #9687A1;--line: #E6E0EB;--line-heavy: #C8BDD1;--shadow-color: rgba(70, 58, 79, .08);--primary: #F5CBCB;--primary-shadow: #8A3B3B;--primary-light: #FBEFEF;--primary-border: #FFE2E2;--secondary: #8B5CF6;--secondary-shadow: #563371;--secondary-light: #F1EDF6;--secondary-border: #C5B3D3;--easy: #10B77F;--easy-shadow: #117453;--easy-light: #EBF9F2;--easy-border: #9CE2C5;--medium: #F59F0A;--medium-shadow: #8E4C0B;--medium-light: #FBF5E9;--medium-border: #EFC78F;--hard: #F43E5C;--hard-shadow: #9C162D;--hard-light: #FBEAED;--hard-border: #EBA2AF;--pointer-head: #ccd2dd;--pointer-head-ink: var(--ink);--pointer-prev: #f4c2c2;--pointer-prev-ink: var(--ink);--pointer-curr: #e0e8c3;--pointer-curr-ink: #2D3436;--pointer-next: #f9e4bc;--pointer-next-ink: #7A5000;--editor-bg: #1E1E2E;--editor-bg-2: #181825;--editor-border: #2D2E3E;--editor-ink: #CBD5E1;--editor-ink-2: #64748B;--editor-ghost: #2D3543;--editor-ghost-hover: #3A4354;--sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;--mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace}@media(prefers-color-scheme:dark){:root:not([data-theme=light]){color-scheme:dark;--bg-color: #150F1A;--card: #22182A;--surface-2: #30213B;--surface-3: #3D2A4B;--ink: #EBE6F0;--ink-2: #B09DBE;--ink-3: #7D6490;--line: #4A3659;--line-heavy: #644979;--shadow-color: rgba(10, 8, 15, .4);--primary: #DF9090;--primary-shadow: #F3CECE;--primary-light: #422424;--primary-border: #6E3535;--secondary: #B88CD9;--secondary-shadow: #E3D0F1;--secondary-light: #301F3D;--secondary-border: #503267;--easy: #64D8B1;--easy-shadow: #D0F1E3;--easy-light: #214536;--easy-border: #3C7C61;--medium: #F0B44C;--medium-shadow: #F3E5CE;--medium-light: #453821;--medium-border: #836A3F;--hard: #EF6C82;--hard-shadow: #F5D6DB;--hard-light: #4C242B;--hard-border: #8A424E;--pointer-head: #423A52;--pointer-head-ink: #D7D2E3;--pointer-prev: #5C2E35;--pointer-prev-ink: #F3CECE;--pointer-curr: #3A4326;--pointer-curr-ink: #D7E2B8;--pointer-next: #4A3A17;--pointer-next-ink: #F3D98C}}:root[data-theme=dark]{color-scheme:dark;--bg-color: #150F1A;--card: #22182A;--surface-2: #30213B;--surface-3: #3D2A4B;--ink: #EBE6F0;--ink-2: #B09DBE;--ink-3: #7D6490;--line: #4A3659;--line-heavy: #644979;--shadow-color: rgba(10, 8, 15, .4);--primary: #DF9090;--primary-shadow: #F3CECE;--primary-light: #422424;--primary-border: #6E3535;--secondary: #B88CD9;--secondary-shadow: #E3D0F1;--secondary-light: #301F3D;--secondary-border: #503267;--easy: #64D8B1;--easy-shadow: #D0F1E3;--easy-light: #214536;--easy-border: #3C7C61;--medium: #F0B44C;--medium-shadow: #F3E5CE;--medium-light: #453821;--medium-border: #836A3F;--hard: #EF6C82;--hard-shadow: #F5D6DB;--hard-light: #4C242B;--hard-border: #8A424E;--pointer-head: #423A52;--pointer-head-ink: #D7D2E3;--pointer-prev: #5C2E35;--pointer-prev-ink: #F3CECE;--pointer-curr: #3A4326;--pointer-curr-ink: #D7E2B8;--pointer-next: #4A3A17;--pointer-next-ink: #F3D98C}*{box-sizing:border-box}html,body{margin:0;padding:0;min-height:100vh}body{font-family:var(--sans);color:var(--ink);line-height:1.6;background:var(--bg-color);-webkit-font-smoothing:antialiased;font-variant-ligatures:none;transition:background .2s ease,color .2s ease}a{text-decoration:none;color:inherit}code{font-family:var(--mono);background:var(--secondary-light);padding:2px 7px;border-radius:6px;font-size:.9em;font-weight:600;color:var(--secondary-shadow)}.diff{font-size:12px;font-weight:700;padding:4px 13px;border-radius:100px;text-transform:uppercase;letter-spacing:.4px;display:inline-block;border:1px solid transparent}.diff.easy{background:var(--easy-light);color:var(--easy-shadow);border-color:var(--easy-border)}.diff.medium{background:var(--medium-light);color:var(--medium-shadow);border-color:var(--medium-border)}.diff.hard{background:var(--hard-light);color:var(--hard-shadow);border-color:var(--hard-border)}.topbar{display:flex;align-items:center;gap:8px;padding:12px 24px;background:var(--card);border-radius:100px;margin:20px auto 28px;max-width:1150px;width:calc(100% - 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32px)}.topbar .nav-links{order:3;width:100%;flex-wrap:wrap;justify-content:center;gap:8px 16px;margin-right:0}.topbar .coffee-btn{padding:8px 12px;font-size:12px}.topbar .logo .logo-mark{height:44px;width:auto}}.wrap{max-width:1150px;margin:0 auto;padding:0 24px 60px}@media(max-width:600px){.wrap{padding:0 16px 48px}}[data-codelang=cpp] .code-java,[data-codelang=java] .code-cpp{display:none!important}.visual-box{direction:ltr}.prose-text.rtl{direction:rtl;text-align:right;font-family:Tajawal,sans-serif}.prose-text.rtl code{direction:ltr;display:inline-block}@keyframes popIn{0%{opacity:0;transform:scale(.98) translateY(6px)}to{opacity:1;transform:scale(1) translateY(0)}}