@import "https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap";
:root{--orange-50:#fff7ed;--orange-100:#ffedd5;--orange-200:#fed7aa;--orange-300:#fdba74;--orange-400:#fb923c;--orange-500:#f97316;--orange-600:#ea580c;--orange-700:#c2410c;--orange-800:#9a3412;--orange-900:#7c2d12;--primary:#ff6b00;--primary-light:#ff9500;--primary-dark:#e05500;--primary-glow:#ff6b0066;--primary-glow-strong:#ff6b00b3;--bg-root:#0a0a0c;--bg-primary:#101014;--bg-secondary:#16161c;--bg-tertiary:#1c1c24;--bg-elevated:#22222c;--bg-card:#101014f2;--bg-glass:#16161c80;--text-primary:#f5f5f7;--text-secondary:#a1a1aa;--text-muted:#71717a;--text-accent:var(--primary-light);--border-subtle:#ffffff0f;--border-default:#ffffff1a;--border-orange:#ff6b004d;--border-orange-strong:#ff6b0099;--shadow-sm:0 2px 8px #0000004d;--shadow-md:0 4px 16px #0006;--shadow-lg:0 8px 32px #00000080;--shadow-xl:0 16px 48px #0009;--shadow-orange:0 4px 24px #ff6b0033;--shadow-orange-lg:0 8px 40px #ff6b004d;--shadow-3d:0 20px 60px #00000080, 0 0 40px #ff6b001a;--space-xs:.25rem;--space-sm:.5rem;--space-md:1rem;--space-lg:1.5rem;--space-xl:2rem;--space-2xl:3rem;--space-3xl:4rem;--radius-sm:8px;--radius-md:12px;--radius-lg:16px;--radius-xl:24px;--radius-2xl:32px;--radius-full:9999px;--ease-out:cubic-bezier(.16, 1, .3, 1);--ease-bounce:cubic-bezier(.34, 1.56, .64, 1);--ease-spring:cubic-bezier(.175, .885, .32, 1.275);--transition-fast:.15s var(--ease-out);--transition-normal:.3s var(--ease-out);--transition-slow:.5s var(--ease-out);--transition-3d:.4s var(--ease-spring);--perspective:1000px;--perspective-close:600px;--perspective-far:1500px;--diff-beginner:#22c55e;--diff-easy:#3b82f6;--diff-medium:#f59e0b;--diff-hard:#ef4444;--diff-extreme:#dc143c;--success:#22c55e;--warning:#f59e0b;--error:#ef4444;--info:#3b82f6}*,:before,:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-size:16px}body{background:var(--bg-root);color:var(--text-primary);min-height:100vh;font-family:Space Grotesk,-apple-system,BlinkMacSystemFont,sans-serif;line-height:1.6;overflow-x:hidden}body:before{content:"";pointer-events:none;z-index:0;background:radial-gradient(80% 50% at 20% 40%,#ff6b0014 0%,#0000 60%),radial-gradient(60% 40% at 80% 20%,#ff95000d 0%,#0000 50%),radial-gradient(50% 60% at 50% 80%,#ff6b000a 0%,#0000 50%);width:100%;height:100%;animation:8s ease-in-out infinite alternate bgPulse;position:fixed;top:0;left:0}@keyframes bgPulse{0%{opacity:.6}to{opacity:1}}a{color:var(--primary-light);transition:color var(--transition-fast);text-decoration:none}a:hover{color:var(--primary)}h1,h2,h3,h4,h5,h6{letter-spacing:-.02em;font-weight:600;line-height:1.2}code,pre{font-family:JetBrains Mono,Fira Code,monospace}.card-3d,.card-3d-deep{background:var(--bg-card);border:1px solid var(--border-subtle);border-radius:var(--radius-lg);-webkit-backdrop-filter:blur(20px);transition:all var(--transition-3d);transform-style:preserve-3d;position:relative;overflow:hidden}.card-3d{perspective:var(--perspective)}.card-3d:before,.card-3d-deep:before{content:"";border-radius:inherit;opacity:0;transition:opacity var(--transition-normal);pointer-events:none;background:linear-gradient(135deg,#ff6b000d 0%,#0000 50%);position:absolute;inset:0}.card-3d:hover{border-color:var(--border-orange);box-shadow:var(--shadow-3d);transform:translateY(-4px)rotateX(2deg)rotateY(-2deg)}.card-3d:hover:before,.card-3d-deep:hover:before{opacity:1}.card-3d-deep{perspective:var(--perspective-close)}.card-3d-deep:hover{border-color:var(--border-orange);box-shadow:var(--shadow-3d), 0 0 60px #ff6b0026;transform:translateY(-8px)rotateX(4deg)rotateY(-3deg)scale(1.02)}.glass{background:var(--bg-glass);-webkit-backdrop-filter:blur(24px)saturate(180%);border:1px solid var(--border-subtle);border-radius:var(--radius-lg)}.glass-orange{-webkit-backdrop-filter:blur(24px)saturate(180%);border:1px solid var(--border-orange);border-radius:var(--radius-lg);background:#ff6b0014}.btn{justify-content:center;align-items:center;gap:var(--space-sm);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-normal);transform-style:preserve-3d;letter-spacing:.01em;border:none;padding:.75rem 1.5rem;font-family:Space Grotesk,sans-serif;font-size:.95rem;font-weight:600;display:inline-flex;position:relative}.btn:active{transform:scale(.96)translateY(2px)}.btn-primary{background:linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);color:#fff;box-shadow:0 4px 0 var(--primary-dark), 0 6px 20px #ff6b004d}.btn-primary:hover{box-shadow:0 6px 0 var(--primary-dark), 0 10px 30px #ff6b0066;transform:translateY(-2px)}.btn-primary:active{box-shadow:0 2px 0 var(--primary-dark), 0 3px 10px #ff6b0033;transform:translateY(2px)}.btn-ghost{color:var(--text-primary);border:1px solid var(--border-default);background:0 0}.btn-ghost:hover{border-color:var(--border-orange);color:var(--primary-light);box-shadow:var(--shadow-orange);background:#ff6b0014;transform:translateY(-2px)}.btn-lg{border-radius:var(--radius-lg);padding:1rem 2.5rem;font-size:1.1rem}.btn-sm{padding:.5rem 1rem;font-size:.85rem}.input{width:100%;color:var(--text-primary);background:var(--bg-secondary);border:1px solid var(--border-subtle);border-radius:var(--radius-md);transition:all var(--transition-normal);outline:none;padding:.75rem 1rem;font-family:Space Grotesk,sans-serif;font-size:.95rem}.input:focus{border-color:var(--primary);box-shadow:0 0 0 3px #ff6b0026, var(--shadow-orange);background:var(--bg-tertiary)}.input::placeholder{color:var(--text-muted)}textarea.input{resize:vertical;min-height:100px}.badge{text-transform:uppercase;letter-spacing:.05em;border-radius:var(--radius-full);border:1px solid #0000;align-items:center;gap:4px;padding:.25rem .75rem;font-size:.75rem;font-weight:600;display:inline-flex}.badge-beginner{color:var(--diff-beginner);background:#22c55e26;border-color:#22c55e4d}.badge-easy{color:var(--diff-easy);background:#3b82f626;border-color:#3b82f64d}.badge-medium{color:var(--diff-medium);background:#f59e0b26;border-color:#f59e0b4d}.badge-hard{color:var(--diff-hard);background:#ef444426;border-color:#ef44444d}.badge-extreme{color:var(--diff-extreme);background:#dc143c26;border-color:#dc143c4d}@keyframes fadeInUp{0%{opacity:0;transform:translateY(30px)scale(.97)}to{opacity:1;transform:translateY(0)scale(1)}}.animate-fade-in-up{animation:fadeInUp .6s var(--ease-out) both}.stagger-children>:first-child{animation-delay:50ms}.stagger-children>:nth-child(2){animation-delay:.1s}.stagger-children>:nth-child(3){animation-delay:.15s}.stagger-children>:nth-child(4){animation-delay:.2s}.stagger-children>:nth-child(5){animation-delay:.25s}.stagger-children>:nth-child(6){animation-delay:.3s}.stagger-children>:nth-child(7){animation-delay:.35s}.stagger-children>:nth-child(8){animation-delay:.4s}@keyframes float{0%,to{transform:translateY(0)rotateX(0)}50%{transform:translateY(-15px)rotateX(3deg)}}.animate-float{animation:float 6s var(--ease-out) infinite}.animate-float-delayed{animation:float 6s var(--ease-out) 2s infinite}@keyframes orbit{0%{transform:rotate(0)translate(120px)rotate(0)}to{transform:rotate(360deg)translate(120px)rotate(-360deg)}}.animate-orbit{animation:20s linear infinite orbit}@keyframes pulseGlow{0%,to{box-shadow:0 0 20px #ff6b0033}50%{box-shadow:0 0 40px #ff6b0066}}.animate-pulse-glow{animation:3s ease-in-out infinite pulseGlow}@keyframes spinSlow{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.animate-spin-slow{animation:30s linear infinite spinSlow}@keyframes gradientFlow{0%{background-position:0%}50%{background-position:100%}to{background-position:0%}}.animate-gradient{background-size:200% 200%;animation:4s infinite gradientFlow}@keyframes scaleIn{0%{opacity:0;transform:scale(.8)}to{opacity:1;transform:scale(1)}}.animate-scale-in{animation:scaleIn .5s var(--ease-bounce) both}@keyframes slideInLeft{0%{opacity:0;transform:translate(-40px)}to{opacity:1;transform:translate(0)}}.animate-slide-left{animation:slideInLeft .6s var(--ease-out) both}@keyframes slideInRight{0%{opacity:0;transform:translate(40px)}to{opacity:1;transform:translate(0)}}.animate-slide-right{animation:slideInRight .6s var(--ease-out) both}@keyframes blink{0%,to{opacity:1}50%{opacity:0}}.cursor-blink:after{content:"|";color:var(--primary);animation:1s ease-in-out infinite blink}@keyframes countUp{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.particles-container{pointer-events:none;z-index:0;position:fixed;inset:0;overflow:hidden}.particle{color:#ff6b001f;will-change:transform;font-family:JetBrains Mono,monospace;font-size:1rem;animation:linear infinite floatParticle;position:absolute}@keyframes floatParticle{0%{opacity:0;transform:translateY(100vh)rotate(0)}10%{opacity:1}90%{opacity:1}to{opacity:0;transform:translateY(-10vh)rotate(360deg)}}.navbar{z-index:1000;padding:0 var(--space-xl);-webkit-backdrop-filter:blur(20px)saturate(180%);border-bottom:1px solid var(--border-subtle);height:72px;transition:all var(--transition-normal);background:#0a0a0ccc;justify-content:space-between;align-items:center;display:flex;position:fixed;top:0;left:0;right:0}.navbar-logo{align-items:center;gap:var(--space-sm);color:var(--text-primary);font-size:1.3rem;font-weight:700;text-decoration:none;display:flex}.navbar-logo span{background:linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.navbar-links{align-items:center;gap:var(--space-lg);list-style:none;display:flex}.navbar-links a{color:var(--text-secondary);transition:color var(--transition-fast);padding:.5rem 0;font-size:.9rem;font-weight:500;position:relative}.navbar-links a:after{content:"";background:linear-gradient(90deg, var(--primary), var(--primary-light));width:0;height:2px;transition:width var(--transition-normal);border-radius:2px;position:absolute;bottom:-4px;left:0}.navbar-links a:hover{color:var(--text-primary)}.navbar-links a:hover:after{width:100%}.navbar-actions{align-items:center;gap:var(--space-md);display:flex}.section{z-index:1;padding:var(--space-3xl) var(--space-xl);max-width:1200px;margin:0 auto;position:relative}.section-header{text-align:center;margin-bottom:var(--space-3xl)}.section-header h2{margin-bottom:var(--space-md);font-size:2.5rem}.section-header p{color:var(--text-secondary);max-width:600px;margin:0 auto;font-size:1.1rem}.gradient-text{background:linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 50%, gold 100%);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.gradient-text-subtle{background:linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.grid-2{gap:var(--space-lg);grid-template-columns:repeat(2,1fr);display:grid}.grid-3{gap:var(--space-lg);grid-template-columns:repeat(3,1fr);display:grid}.grid-4{gap:var(--space-lg);grid-template-columns:repeat(4,1fr);display:grid}.reveal{opacity:0;transition:all .8s var(--ease-out);transform:translateY(30px)}.reveal.visible{opacity:1;transform:translateY(0)}.streak-cell{background:var(--bg-tertiary);width:14px;height:14px;transition:all var(--transition-fast);border-radius:3px}.streak-cell.active-1{background:#ff6b0033}.streak-cell.active-2{background:#ff6b0066}.streak-cell.active-3{background:#ff6b0099}.streak-cell.active-4{background:var(--primary)}@media (max-width:1024px){.grid-3,.grid-4{grid-template-columns:repeat(2,1fr)}}@media (max-width:768px){.section{padding:var(--space-2xl) var(--space-md)}.section-header h2{font-size:1.8rem}.grid-2,.grid-3,.grid-4{grid-template-columns:1fr}.navbar-links{display:none}}@media (max-width:480px){html{font-size:14px}.btn-lg{padding:.875rem 1.5rem;font-size:1rem}.navbar{padding:0 var(--space-md);height:60px}.navbar-logo{gap:6px;font-size:1.1rem}.navbar-actions{gap:8px}}.text-center{text-align:center}.text-left{text-align:left}.text-right{text-align:right}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-center{justify-content:center}.justify-between{justify-content:space-between}.gap-sm{gap:var(--space-sm)}.gap-md{gap:var(--space-md)}.gap-lg{gap:var(--space-lg)}.gap-xl{gap:var(--space-xl)}.w-full{width:100%}.relative{position:relative}.z-1{z-index:1}.overflow-hidden{overflow:hidden}.mt-sm{margin-top:var(--space-sm)}.mt-md{margin-top:var(--space-md)}.mt-lg{margin-top:var(--space-lg)}.mt-xl{margin-top:var(--space-xl)}.mb-sm{margin-bottom:var(--space-sm)}.mb-md{margin-bottom:var(--space-md)}.mb-lg{margin-bottom:var(--space-lg)}.mb-xl{margin-bottom:var(--space-xl)}:root{--promo-banner-height:56px}body.promo-banner-active:not(.promo-banner-session) .page,body.promo-banner-active:not(.promo-banner-session) [class*=page]{padding-top:calc(72px + var(--promo-banner-height))!important}@media (max-width:768px){:root{--promo-banner-height:100px}}@media (max-width:480px){body.promo-banner-active:not(.promo-banner-session) .page,body.promo-banner-active:not(.promo-banner-session) [class*=page]{padding-top:calc(60px + var(--promo-banner-height))!important}}