:root{color-scheme:light;--brand-orange:#FF5A00;--brand-orange-dim:rgba(255,90,0,0.08);--brand-orange-glow:rgba(255,90,0,0.25);--track-logic:#0EA5E9;--track-algebra:#FF5A00;--track-calculus:#7C3AED;--color-green:#16A34A;--color-green-dim:rgba(22,163,74,0.08);--color-red:#EF4444;--color-red-dim:rgba(239,68,68,0.06);--surface-base:#F8F9FA;--surface-paper:#FFFFFF;--surface-chalk:#F1F3F5;--text-ink:#0A0D14;--text-graph:#495057;--text-notation:#868E96;--border-light:rgba(0,0,0,0.09);--grid-major:rgba(0,0,0,0.05);--shadow-float:0 16px 48px -12px rgba(10,13,20,0.1);--shadow-glow:0 0 28px var(--brand-orange-glow);--nav-bg:rgba(248,249,250,0.92);--font-serif:"Playfair Display",serif;--font-sans:"Inter",system-ui,sans-serif;--font-mono:"JetBrains Mono",monospace;--radius-sharp:0px;--radius-control:10px;--radius-card:18px;--radius-pill:999px;--radius:var(--radius-sharp);--bg-absolute:var(--surface-base);--bg-paper:var(--surface-paper);--bg-chalk:var(--surface-chalk)}[data-theme=dark]{color-scheme:dark;--brand-orange-dim:rgba(255,90,0,0.15);--brand-orange-glow:rgba(255,90,0,0.35);--track-logic:#22D3EE;--track-algebra:#FF5A00;--track-calculus:#7B61FF;--color-green:#22C55E;--color-green-dim:rgba(34,197,94,0.14);--color-red:#F87171;--color-red-dim:rgba(248,113,113,0.1);--surface-base:#030406;--surface-paper:#080A0F;--surface-chalk:#11151C;--text-ink:#F8F9FA;--text-graph:#ADB5BD;--text-notation:#6C757D;--border-light:rgba(255,255,255,0.1);--grid-major:rgba(255,255,255,0.05);--shadow-float:0 24px 60px -12px rgba(0,0,0,0.7);--nav-bg:rgba(3,4,6,0.9);--bg-absolute:var(--surface-base);--bg-paper:var(--surface-paper);--bg-chalk:var(--surface-chalk)}*,:after,:before{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body,html{min-height:100dvh}*,:after,:before{transition:background-color .22s ease,color .22s ease,border-color .22s ease,box-shadow .22s ease}.katex,.katex *{transition:none!important}svg,svg *{transition:none}body{background-color:var(--surface-base);color:var(--text-ink);font-family:var(--font-sans);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;line-height:1.6;overflow-x:hidden}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border-light)}::-webkit-scrollbar-thumb:hover{background:var(--text-notation)}::selection{background:var(--brand-orange);color:#fff}:focus-visible{outline:2px solid var(--brand-orange);outline-offset:2px}.katex{color:inherit;font-size:1.05em}.katex-display{padding:.5rem 0;text-align:left}.btn-primary{display:inline-flex;align-items:center;gap:.5rem;background:var(--brand-orange);color:#fff;border:1px solid var(--brand-orange);border-radius:var(--radius-pill);font-family:var(--font-mono);font-size:.75rem;letter-spacing:.1em;text-transform:uppercase;padding:.75rem 1.75rem;text-decoration:none;cursor:pointer;transition:background .18s ease,color .18s ease}.btn-primary:hover{background:transparent;color:var(--brand-orange)}.btn-outline{display:inline-flex;align-items:center;gap:.5rem;background:transparent;color:var(--text-graph);border:1px solid var(--border-light);border-radius:var(--radius-control);font-family:var(--font-mono);font-size:.75rem;letter-spacing:.1em;text-transform:uppercase;padding:.75rem 1.75rem;text-decoration:none;cursor:pointer;transition:border-color .18s ease,color .18s ease}.btn-outline:hover{border-color:var(--brand-orange);color:var(--brand-orange)}.badge-pill{display:inline-flex;align-items:center;gap:.4rem;font-family:var(--font-mono);font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;padding:.4rem .9rem;border-radius:var(--radius-pill);font-weight:600;background:var(--brand-orange-dim);color:var(--brand-orange)}.bp-grid{position:absolute;inset:0;pointer-events:none;background-image:linear-gradient(var(--grid-major) 1px,transparent 1px),linear-gradient(90deg,var(--grid-major) 1px,transparent 1px);background-size:24px 24px}@keyframes fadeInUp{0%{opacity:0;transform:translateY(14px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes popIn{0%{opacity:0;transform:scale(.85)}60%{opacity:1;transform:scale(1.03)}to{opacity:1;transform:scale(1)}}@keyframes pulseDot{0%,to{box-shadow:0 0 0 0 var(--brand-orange-glow)}50%{box-shadow:0 0 0 6px transparent}}@keyframes shimmer{0%{background-position:-200% 0}to{background-position:200% 0}}@keyframes shake{10%,90%{transform:translateX(-1px)}20%,80%{transform:translateX(2px)}30%,50%,70%{transform:translateX(-4px)}40%,60%{transform:translateX(4px)}}@keyframes floatSlow{0%,to{transform:translateY(0)}50%{transform:translateY(-8px)}}@keyframes spin{to{transform:rotate(1turn)}}@keyframes underlineIn{0%{transform:scaleX(0)}to{transform:scaleX(1)}}.anim-fade-up{animation:fadeInUp .55s cubic-bezier(.16,1,.3,1) both}.anim-pop{animation:popIn .4s cubic-bezier(.34,1.56,.64,1) both}.anim-shake{animation:shake .45s ease}.anim-float{animation:floatSlow 5s ease-in-out infinite}.anim-spin{animation:spin .9s linear infinite}@media (prefers-reduced-motion:reduce){*,:after,:before{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}}a:not([class]){color:inherit;text-decoration:none;transition:color .15s ease}a:not([class]):hover{color:var(--brand-orange)}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--brand-orange);outline-offset:3px}input[type=email],input[type=password],input[type=text]{transition:border-color .16s ease,box-shadow .16s ease,transform .1s ease}input[type=email]:hover,input[type=password]:hover,input[type=text]:hover{border-color:var(--text-notation)!important}input[type=email]:focus,input[type=password]:focus,input[type=text]:focus{border-color:var(--brand-orange)!important;box-shadow:0 0 0 3px var(--brand-orange-dim)}.btn-outline,.btn-primary,button{transition:background-color .16s ease,color .16s ease,border-color .16s ease,transform .12s cubic-bezier(.34,1.56,.64,1),box-shadow .16s ease}.btn-outline:hover,.btn-primary:hover,button:not(:disabled):hover{transform:translateY(-1px)}.btn-outline:active,.btn-primary:active,button:not(:disabled):active{transform:translateY(0) scale(.97)}.btn-primary:hover{box-shadow:0 6px 20px -4px var(--brand-orange-glow)}.link-underline{position:relative;text-decoration:none}.link-underline:after{content:"";position:absolute;left:0;right:0;bottom:-2px;height:1px;background:currentColor;transform:scaleX(0);transform-origin:left;transition:transform .22s ease}.link-underline:hover:after{transform:scaleX(1)}.track-card{border-radius:var(--radius-card);overflow:hidden;transition:border-color .2s ease,transform .22s cubic-bezier(.16,1,.3,1),box-shadow .22s ease,background-color .2s ease;box-shadow:0 2px 12px -4px rgba(10,13,20,.06);will-change:transform}.track-card:hover{transform:translateY(-6px) scale(1.012);box-shadow:0 24px 48px -16px color-mix(in srgb,var(--track-color,var(--brand-orange)) 40%,transparent)}.track-card:active{transform:translateY(-1px) scale(.995)}.track-card .track-arrow{display:inline-block;transition:transform .22s cubic-bezier(.34,1.56,.64,1)}.track-card:hover .track-arrow{transform:translateX(5px)}.track-card .track-solved-dot{animation:pulseDot 2s ease-in-out infinite}.archive-row{transition:background-color .16s ease,transform .16s ease}.archive-row:hover{background-color:var(--surface-chalk)!important}.archive-row:hover .archive-row-cta span{transform:translateX(4px)}.header-logo:hover .header-logo-mark{transform:rotate(-6deg) scale(1.08)}.header-logo-mark{transition:transform .25s cubic-bezier(.34,1.56,.64,1);display:inline-block}.mobile-menu-btn{display:none}.mobile-menu-panel{animation:fadeInUp .22s ease both}.katex-display{overflow-y:hidden;padding:.75rem 0}.katex-display,.katex-display>.katex{overflow-x:auto;max-width:100%}.katex:not(.katex-display>.katex),.prompt-content{white-space:normal}.prompt-content{max-width:100%;overflow-wrap:break-word;word-break:break-word;line-height:1.85}.prompt-content p{margin:0 0 .75rem}.prompt-content p:last-child{margin-bottom:0}.page-container{max-width:1280px;margin:0 auto;padding:0 clamp(1rem,4vw,3rem)}.puzzle-section{max-width:100%;overflow:hidden}.countdown-chip{display:flex;flex-direction:column;align-items:center;gap:.15rem;min-width:3rem;padding:.5rem .25rem;border-radius:var(--radius-control);background:var(--surface-chalk);border:1px solid var(--border-light)}.countdown-chip .countdown-chip-value{font-family:var(--font-mono);font-weight:800;font-feature-settings:"tnum";font-variant-numeric:tabular-nums;font-size:clamp(1.1rem,4vw,1.6rem);color:var(--text-ink);line-height:1}.countdown-chip .countdown-chip-unit{font-family:var(--font-mono);font-size:.55rem;letter-spacing:.1em;text-transform:uppercase;color:var(--text-notation)}.logo-badge{display:inline-flex;align-items:center;justify-content:center;width:1.75rem;height:1.75rem;border-radius:var(--radius-control);background:var(--brand-orange);color:#fff;font-family:var(--font-serif);font-weight:700;flex-shrink:0}.skeleton{background:linear-gradient(90deg,var(--surface-chalk) 25%,var(--border-light) 50%,var(--surface-chalk) 75%);background-size:200% 100%;animation:shimmer 1.6s ease-in-out infinite}button,input,select{min-height:44px}body,html{overflow-x:hidden;max-width:100vw}@media (max-width:900px){.page-container{padding:0 clamp(1rem,5vw,2rem)}}@media (max-width:768px){.auth-grid{grid-template-columns:1fr!important}.auth-brand-panel{display:none!important}.home-header-row{flex-direction:column!important;align-items:flex-start!important;gap:1.25rem!important}.home-header-row>:last-child{align-self:stretch!important;text-align:left!important}}@media (max-width:640px){.track-grid,.track-section{grid-template-columns:1fr!important}.header-nav-links{display:none!important}.header-nav-links-mobile{display:flex!important}.mobile-menu-btn{display:inline-flex!important}h1{word-break:break-word}.archive-track-grid{grid-template-columns:1fr!important}}@media (max-width:480px){.header-nav-link{display:none}.hide-mobile{display:none!important}}