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1.25rem/1.35;--os-type-headline-en:600 1.8125rem/1.18;--os-type-display-en:700 2.75rem/1.06;--os-type-hero-en:700 4.25rem/1;--os-motion-fast:.14s;--os-motion-base:.24s;--os-motion-slow:.42s;--os-motion-dock:.32s;--os-easing:cubic-bezier(.22, 1, .36, 1);--os-easing-in-out:cubic-bezier(.65, 0, .35, 1);--os-spring:cubic-bezier(.34, 1.56, .64, 1);--os-measure:42.5rem;--os-content:80rem;--os-touch-target:2.75rem;--os-rail:72px;--os-dock:64px}:root,[data-theme=light]{--lightningcss-light:initial;--lightningcss-dark: 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#ff6a1a8c;--os-stage:#f4f6fa;--os-stage-2:#fff;--os-stage-grid:#dde2ea;--os-stage-grid-2:#cdd4df;--os-stage-line:#c3cbd6;--os-stage-ink:#1d1d1f;--os-stage-ink-2:#454b54;--os-stage-ink-3:#646b75;--os-stage-ctl:#e8590c;--os-stage-measure:#0071e3;--os-stage-ok:#15803d;--os-stage-bad:#dc2626;--os-stage-caution:#b45309;--os-stage-s1:#e8590c;--os-stage-s2:#0071e3;--os-stage-s3:#7c3aed;--os-stage-s4:#15803d;--os-stage-s5:#b45309;--os-stage-s6:#db2777;--sp-violet:#7c4dff;--sp-violet-ink:#5b2fe0;--sp-blue:#2f80ff;--sp-blue-ink:#1557c9;--sp-cyan:#11c5d6;--sp-cyan-ink:#0a7380;--sp-green:#1fc16b;--sp-green-ink:#137a3e;--sp-yellow:#ffc22e;--sp-yellow-ink:#8a5a00;--sp-orange:#ff6a1a;--sp-orange-ink:#c2410c;--sp-red:#ff4b4b;--sp-red-ink:#c42828;--sp-pink:#ff4fa3;--sp-pink-ink:#b81b63}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--os-hull:#06070b;--os-panel:#10121a;--os-panel-2:#171a24;--os-line:#252938;--os-line-2:#3a3f52;--os-ink:#f3f4f8;--os-ink-2:#b9becd;--os-ink-3:#8c92a6;--os-go:#ff7a2e;--os-go-ink:#ff9254;--os-on-go:#0e0f14;--os-tel:#3b9eff;--os-tel-ink:#6db3ff;--os-ok:#30d158;--os-bad:#ff5a52;--os-caution:#ffd60a;--os-signal:#ffc048;--os-signal-ink:#1f1400;--os-go-soft:#3c2926;--os-tel-soft:#1d2f47;--os-bad-soft:#3c242b;--os-caution-soft:#3c3820;--os-paper:#06070b;--os-sheet:#171a24;--os-grid:#252938;--os-accent:#ff9254;--os-accent-ink:#0e0f14;--os-red:#ff5a52;--os-hi:#ffd60a;--os-hi-ink:#1f1400;--os-warn:#ffd60a;--os-accent-soft:#3c2d2c;--os-red-soft:#3c242b;--os-hi-soft:#534b1d;--os-ok-soft:#1b372c;--os-warn-soft:#3c3820;--os-elev-flat:none;--os-elev-raised:0 0 0 1px #ffffff12 inset, 0 1px 0 #ffffff0d inset, 0 8px 24px -12px #000000b3;--os-elev-lifted:0 0 0 1px #ffffff17 inset, 0 1px 0 #ffffff12 inset, 0 28px 64px -16px #000000d9;--os-elev-glow:0 0 0 4px #ff7a2e38, 0 8px 28px -6px #ff7a2e8c;--os-stage:#0d1017;--os-stage-2:#171b24;--os-stage-grid:#1f2531;--os-stage-grid-2:#2a3140;--os-stage-line:#343c4c;--os-stage-ink:#f2f4f8;--os-stage-ink-2:#aeb6c3;--os-stage-ink-3:#8590a0;--os-stage-ctl:#ff7a2e;--os-stage-measure:#3b9eff;--os-stage-ok:#34d399;--os-stage-bad:#ff5a52;--os-stage-caution:#ffc93c;--os-stage-s1:#ff7a2e;--os-stage-s2:#3b9eff;--os-stage-s3:#b57bff;--os-stage-s4:#34d399;--os-stage-s5:#ffc93c;--os-stage-s6:#ff5c9a;--sp-violet:#9b7bff;--sp-violet-ink:#b9a3ff;--sp-blue:#4d9cff;--sp-blue-ink:#8cc0ff;--sp-cyan:#3fe0d0;--sp-cyan-ink:#6feadd;--sp-green:#4be38a;--sp-green-ink:#85e9a6;--sp-yellow:#ffd25a;--sp-yellow-ink:#ffdb7a;--sp-orange:#ff8a3d;--sp-orange-ink:#ffa066;--sp-red:#ff6b6b;--sp-red-ink:#ff9a92;--sp-pink:#ff6fb0;--sp-pink-ink:#ff9cc7}}[data-theme=dark]{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--os-hull:#06070b;--os-panel:#10121a;--os-panel-2:#171a24;--os-line:#252938;--os-line-2:#3a3f52;--os-ink:#f3f4f8;--os-ink-2:#b9becd;--os-ink-3:#8c92a6;--os-go:#ff7a2e;--os-go-ink:#ff9254;--os-on-go:#0e0f14;--os-tel:#3b9eff;--os-tel-ink:#6db3ff;--os-ok:#30d158;--os-bad:#ff5a52;--os-caution:#ffd60a;--os-signal:#ffc048;--os-signal-ink:#1f1400;--os-go-soft:#3c2926;--os-tel-soft:#1d2f47;--os-bad-soft:#3c242b;--os-caution-soft:#3c3820;--os-paper:#06070b;--os-sheet:#171a24;--os-grid:#252938;--os-accent:#ff9254;--os-accent-ink:#0e0f14;--os-red:#ff5a52;--os-hi:#ffd60a;--os-hi-ink:#1f1400;--os-warn:#ffd60a;--os-accent-soft:#3c2d2c;--os-red-soft:#3c242b;--os-hi-soft:#534b1d;--os-ok-soft:#1b372c;--os-warn-soft:#3c3820;--os-elev-flat:none;--os-elev-raised:0 0 0 1px #ffffff12 inset, 0 1px 0 #ffffff0d inset, 0 8px 24px -12px #000000b3;--os-elev-lifted:0 0 0 1px #ffffff17 inset, 0 1px 0 #ffffff12 inset, 0 28px 64px -16px #000000d9;--os-elev-glow:0 0 0 4px #ff7a2e38, 0 8px 28px -6px #ff7a2e8c;--os-stage:#0d1017;--os-stage-2:#171b24;--os-stage-grid:#1f2531;--os-stage-grid-2:#2a3140;--os-stage-line:#343c4c;--os-stage-ink:#f2f4f8;--os-stage-ink-2:#aeb6c3;--os-stage-ink-3:#8590a0;--os-stage-ctl:#ff7a2e;--os-stage-measure:#3b9eff;--os-stage-ok:#34d399;--os-stage-bad:#ff5a52;--os-stage-caution:#ffc93c;--os-stage-s1:#ff7a2e;--os-stage-s2:#3b9eff;--os-stage-s3:#b57bff;--os-stage-s4:#34d399;--os-stage-s5:#ffc93c;--os-stage-s6:#ff5c9a;--sp-violet:#9b7bff;--sp-violet-ink:#b9a3ff;--sp-blue:#4d9cff;--sp-blue-ink:#8cc0ff;--sp-cyan:#3fe0d0;--sp-cyan-ink:#6feadd;--sp-green:#4be38a;--sp-green-ink:#85e9a6;--sp-yellow:#ffd25a;--sp-yellow-ink:#ffdb7a;--sp-orange:#ff8a3d;--sp-orange-ink:#ffa066;--sp-red:#ff6b6b;--sp-red-ink:#ff9a92;--sp-pink:#ff6fb0;--sp-pink-ink:#ff9cc7}
:root{--os-font-display:var(--font-atma), var(--font-atma-bangla), var(--font-symbols), var(--font-math-symbols), "Atma", "Noto Sans Bengali", -apple-system, system-ui, sans-serif;--os-font-body:var(--font-figtree), var(--font-bangla-text), var(--font-symbols), var(--font-math-symbols), "Figtree", "Noto Sans Bengali", -apple-system, system-ui, sans-serif;--os-font-mono:var(--font-jetbrains), "JetBrains Mono", ui-monospace, Menlo, monospace;--ease:var(--os-easing);--spring:var(--os-spring);--gap:1rem;--shell-pad:clamp(16px, 3.4vw, 40px);--radius-tile:28px;--radius-card:22px;--radius-control:14px;--thread:linear-gradient(90deg, var(--sp-violet), var(--sp-blue), var(--sp-cyan), var(--sp-green), var(--sp-yellow), var(--sp-orange), var(--sp-red), var(--sp-pink));--thread-soft:linear-gradient(90deg, color-mix(in srgb, var(--sp-violet) 70%, transparent), color-mix(in srgb, var(--sp-cyan) 70%, transparent), color-mix(in srgb, var(--sp-yellow) 70%, transparent), color-mix(in srgb, 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60px))}.publicbar[data-mode=sims],.publicbar[data-mode=demo]{--pill-w:360px}.publicbar[data-mode=how],.publicbar[data-mode=subjects]{--pill-w:380px}.publicbar[data-mode=page]{--pill-w:640px}.bar-row{justify-content:center;align-items:center;gap:8px;display:flex}.bar-island{width:var(--bar-w);height:var(--bar-h);pointer-events:auto;background:color-mix(in srgb, var(--os-hull) 82%, transparent);-webkit-backdrop-filter:blur(18px)saturate(1.6);backdrop-filter:blur(18px)saturate(1.6);box-shadow:0 0 0 1px color-mix(in srgb, var(--os-ink) 8%, transparent), 0 12px 32px -18px #0e0f1452;transition:width .62s var(--fold), height .62s var(--fold), border-radius .62s var(--fold), background .3s;border-radius:20px;flex:none;position:relative;overflow:hidden}.publicbar[data-folded] .bar-island{width:min(var(--pill-w), calc(100vw - 24px - var(--app-room)));background:color-mix(in srgb, var(--os-panel-2) 90%, transparent);border-radius:999px;height:52px}.bar-face{transition:opacity .32s var(--ease), 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radial-gradient(70% 60% at 50% 30%, color-mix(in srgb, var(--os-go) 9%, transparent), transparent 70%);position:absolute;inset:0}.gate-mark{width:clamp(120px,18vw,220px);height:auto}.gate-orbit{transform-origin:16px 16px;animation:14s linear infinite orbit-spin}.gate-line{font-family:var(--os-font-display);max-width:12ch;font-size:clamp(1.5rem,2.6vw,2.25rem);font-weight:700;line-height:1.2}.gate-pair{align-items:end;margin-bottom:calc(-1*clamp(24px,4vw,48px));display:flex}.gate-pair .mascot+.mascot{margin-left:-14px}@media (max-width:899px){.gate-art{text-align:start;border-radius:24px;grid-template-columns:auto minmax(0,1fr);justify-items:start;gap:14px;padding:18px 20px}.gate-mark{width:56px}.gate-line{font-size:1.375rem}.gate-pair{display:none}}.about{--gap:2.25rem}.about h2{font-size:clamp(1.5rem,2.6vw,2rem);font-weight:800}.about:before{background:linear-gradient(var(--os-go), color-mix(in srgb, var(--os-go) 8%, transparent));width:3px}.utopia-slot{place-items:center;height:clamp(300px,38vw,540px);display:grid}@media (max-width:600px){.utopia-slot{height:calc(59.2593vw + 92px)}}.footer-reach{white-space:nowrap;align-items:center;gap:8px;display:inline-flex}.footer-reach svg{color:var(--os-ink-3);flex:none}.publicbar-me{padding:0 4px}@media (max-width:400px){.publicbar-me{display:none}}.sim-host{container-type:inline-size}.sim-frame[data-loading]{min-height:calc(62.5cqw + 242.5px)}@container (max-width:759px){.sim-frame[data-loading]{min-height:calc(680px + 62.5cqw)}}.sim-frame{position:relative}.sim-frame[data-loading]>[data-sim-id]{visibility:hidden;position:absolute;inset:0 0 auto}.sim-static-ask{gap:14px;margin-bottom:16px;display:grid}.sim-static-ask .ask-problem{font-size:17.5px;line-height:1.75}.sim-static-ask .ask-prompt{color:var(--os-ink-2);font-size:14.5px;font-weight:650}.ask-options{gap:10px;margin:0;padding:0;list-style:none;display:grid}.ask-options li{background:var(--os-panel-2);box-shadow:var(--os-elev-raised);border-radius:16px;grid-template-columns:32px 1fr;align-items:center;gap:14px;padding:14px 16px;font-size:15.5px;line-height:1.55;display:grid}.ask-key{width:32px;height:32px;box-shadow:0 0 0 2px var(--os-line-2) inset;color:var(--os-ink-2);border-radius:50%;place-items:center;font-size:13.5px;font-weight:750;display:grid}@container (max-width:600px){.sim-static-ask{gap:12px}.sim-static-ask .ask-problem{font-size:16.5px;line-height:1.7}.ask-options li{gap:12px;padding:12px 14px;font-size:15px}}