@import "https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;600;800&display=swap";:root{--bg-base:#09090b;--bg-surface:#18181b;--bg-surface-hover:#27272a;--text-primary:#f8fafc;--text-secondary:#a1a1aa;--text-muted:#71717a;--accent-primary:#6366f1;--accent-secondary:#a855f7;--accent-glow:#6366f180;--border-color:#ffffff14;--border-hover:#fff3;--diff-beginner:#34d399;--diff-intermediate:#fbbf24;--diff-advanced:#f87171;--diff-expert:#c084fc;--font-sans:"Inter", system-ui, sans-serif;--font-display:"Outfit", system-ui, sans-serif}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-sans);background-color:var(--bg-base);color:var(--text-primary);-webkit-font-smoothing:antialiased;min-height:100vh;line-height:1.6}a{color:inherit;text-decoration:none}.container{max-width:1200px;margin:0 auto;padding:2rem 1.5rem}.header{border-bottom:1px solid var(--border-color);justify-content:space-between;align-items:center;margin-bottom:4rem;padding:1.5rem 0;display:flex}.logo{font-family:var(--font-display);letter-spacing:-.02em;color:var(--text-primary);align-items:center;gap:.75rem;font-size:1.75rem;font-weight:800;display:flex}.logo-icon{color:var(--accent-primary);filter:drop-shadow(0 0 8px var(--accent-glow))}h1,h2,h3,h4{font-family:var(--font-display);letter-spacing:-.02em;font-weight:800;line-height:1.1}.title{color:var(--text-primary);margin-bottom:1rem;font-size:3rem;font-weight:700}.subtitle{color:var(--text-secondary);margin-bottom:3rem;font-size:1.25rem;font-weight:400}.card{background:var(--bg-surface);border:1px solid var(--border-color);border-radius:8px;padding:1.5rem;transition:border-color .2s}.card.interactive:hover{border-color:var(--text-muted);cursor:pointer}.select-wrapper{max-width:500px;margin:3rem auto;position:relative}.topic-select{appearance:none;background:var(--bg-base);border:1px solid var(--border-color);width:100%;color:var(--text-primary);font-size:1rem;font-family:var(--font-sans);cursor:pointer;border-radius:6px;padding:1rem 1.5rem;transition:border-color .2s}.topic-select:focus{border-color:var(--text-primary);outline:none}.topic-select option{background:var(--bg-base);color:var(--text-primary);padding:10px}.select-icon{color:var(--accent-primary);pointer-events:none;transition:color .3s;position:absolute;top:50%;right:1.5rem;transform:translateY(-50%)}.topic-select:focus+.select-icon{color:var(--accent-secondary)}.btn{background:var(--text-primary);color:var(--bg-base);border:1px solid var(--text-primary);font-size:.9rem;font-family:var(--font-sans);cursor:pointer;border-radius:6px;justify-content:center;align-items:center;gap:.5rem;padding:.6rem 1.2rem;font-weight:500;transition:opacity .2s;display:inline-flex}.btn:hover:not(:disabled){opacity:.9}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-secondary{color:var(--text-primary);border:1px solid var(--border-color);background:0 0}.btn-secondary:hover:not(:disabled){border-color:var(--text-muted);background:var(--bg-surface)}.badge{letter-spacing:.05em;text-transform:uppercase;background:#ffffff0d;border:1px solid #ffffff1a;border-radius:9999px;align-items:center;padding:.25rem .75rem;font-size:.75rem;font-weight:600;display:inline-flex}.badge-beginner{color:var(--diff-beginner);background:#34d3990d;border-color:#34d39933}.badge-intermediate{color:var(--diff-intermediate);background:#fbbf240d;border-color:#fbbf2433}.badge-advanced{color:var(--diff-advanced);background:#f871710d;border-color:#f8717133}.badge-expert{color:var(--diff-expert);background:#c084fc0d;border-color:#c084fc33}.path-container{flex-direction:column;align-items:center;max-width:650px;margin:4rem auto;display:flex}.path-node{width:100%;position:relative}.path-connector{background:var(--border-color);width:1px;height:40px;margin:.5rem auto;position:relative}.path-connector:after{content:"▼";color:var(--text-muted);font-size:.6rem;position:absolute;bottom:-10px;left:50%;transform:translate(-50%)}.step-number{font-family:var(--font-display);color:var(--text-muted);font-size:1.5rem;font-weight:400;position:absolute;top:1.25rem;left:-4rem}.completed-card{background:#34d3990d;border-color:#34d3994d}.completed-card h3{color:var(--text-muted)}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.animate-fade-in{animation:.6s cubic-bezier(.16,1,.3,1) forwards fadeInUp}.loader{border:2px solid var(--border-color);border-top:2px solid var(--text-primary);border-radius:50%;width:30px;height:30px;margin:2rem auto;animation:1s linear infinite spin}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.empty-state{text-align:center;color:var(--text-muted);background:var(--bg-surface);border:1px dashed var(--border-color);border-radius:24px;padding:6rem 2rem}.empty-icon{color:var(--border-hover);margin-bottom:1.5rem;font-size:4rem}.details-grid{grid-template-columns:2fr 1fr;gap:2.5rem;display:grid}@media (width<=768px){.details-grid{grid-template-columns:1fr}}.section-title{font-family:var(--font-display);color:var(--text-primary);border-bottom:1px solid var(--border-color);margin-bottom:1.5rem;padding-bottom:.75rem;font-size:1.5rem}.related-items{flex-wrap:wrap;gap:.75rem;margin-bottom:2.5rem;display:flex}.course-item{border:1px solid var(--border-color);background:var(--bg-surface);border-radius:12px;flex-direction:column;margin-bottom:1rem;padding:1.25rem;transition:all .2s;display:flex}.course-item:hover{border-color:var(--border-hover);transform:translate(4px)}.course-meta{color:var(--text-secondary);justify-content:space-between;margin-top:.75rem;font-size:.875rem;display:flex}input[type=checkbox]{appearance:none;background-color:var(--bg-base);font:inherit;color:currentColor;border:2px solid var(--text-muted);border-radius:.25em;place-content:center;width:1.25em;height:1.25em;margin:0;transition:all .2s;display:grid}input[type=checkbox]:before{content:"";width:.65em;height:.65em;box-shadow:inset 1em 1em var(--bg-base);transform-origin:0 100%;clip-path:polygon(14% 44%,0 65%,50% 100%,100% 16%,80% 0%,43% 62%);background-color:canvastext;transition:transform .12s ease-in-out;transform:scale(0)}input[type=checkbox]:checked{background-color:var(--diff-beginner);border-color:var(--diff-beginner)}input[type=checkbox]:checked:before{transform:scale(1)}input[type=checkbox]:disabled{opacity:.5;cursor:not-allowed}.progress-container{background:var(--bg-base);border:1px solid var(--border-color);border-radius:6px;padding:1.5rem}.progress-track{background-color:var(--bg-surface);border-radius:2px;width:100%;height:4px;overflow:hidden}.progress-fill{background:var(--text-primary);height:100%;transition:width .3s}.graph-container{border:1px solid var(--border-color);background:var(--bg-base);border-radius:8px;justify-content:center;align-items:center;width:100%;height:100%;min-height:600px;display:flex;overflow:hidden}