:root{--primary: #4f46e5;--primary-hover: #4338ca;--primary-light: rgba(79, 70, 229, .1);--secondary: #7c3aed;--accent: #0ea5e9;--success: #10b981;--warning: #f59e0b;--error: #ef4444;--bg-primary: #ffffff;--bg-secondary: #f8fafc;--bg-tertiary: #f1f5f9;--bg-input: #ffffff;--bg-hover: #f1f5f9;--text-primary: #1e293b;--text-secondary: #64748b;--text-muted: #94a3b8;--border-color: #e2e8f0;--border-focus: #4f46e5;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .05);--shadow-md: 0 4px 6px rgba(0, 0, 0, .07);--shadow-lg: 0 10px 25px rgba(0, 0, 0, .1);--spacing-xs: .25rem;--spacing-sm: .5rem;--spacing-md: 1rem;--spacing-lg: 1.5rem;--spacing-xl: 2rem;--spacing-2xl: 3rem;--radius-sm: .375rem;--radius-md: .5rem;--radius-lg: .75rem;--radius-xl: 1rem;--transition-fast: .15s ease;--transition-normal: .25s ease;--font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:var(--font-family);background:var(--bg-secondary);color:var(--text-primary);line-height:1.6;min-height:100vh}.app-container{max-width:800px;margin:0 auto;padding:var(--spacing-lg);min-height:100vh}.hero{text-align:center;padding:var(--spacing-2xl) var(--spacing-lg);background:linear-gradient(135deg,var(--primary-light),rgba(124,58,237,.08));border-radius:var(--radius-xl);margin-bottom:var(--spacing-xl)}.hero-badge{display:inline-block;background:var(--primary);color:#fff;padding:var(--spacing-xs) var(--spacing-md);border-radius:9999px;font-size:.85rem;font-weight:500;margin-bottom:var(--spacing-md)}.hero h1{font-size:2.25rem;font-weight:700;color:var(--text-primary);margin-bottom:var(--spacing-md);line-height:1.2}.hero-description{color:var(--text-secondary);font-size:1.1rem;max-width:600px;margin:0 auto;line-height:1.7}.how-it-works{display:flex;align-items:center;justify-content:center;gap:var(--spacing-md);margin-bottom:var(--spacing-xl);flex-wrap:wrap}.step{display:flex;align-items:center;gap:var(--spacing-sm);background:var(--bg-primary);padding:var(--spacing-sm) var(--spacing-md);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);border:1px solid var(--border-color)}.step-number{display:flex;align-items:center;justify-content:center;width:24px;height:24px;background:var(--primary);color:#fff;border-radius:50%;font-size:.8rem;font-weight:600}.step-text{font-size:.9rem;font-weight:500;color:var(--text-primary)}.step-arrow{color:var(--text-muted);font-size:1.2rem}.input-section{background:var(--bg-primary);border-radius:var(--radius-xl);padding:var(--spacing-xl);border:1px solid var(--border-color);box-shadow:var(--shadow-sm)}.input-group{margin-bottom:var(--spacing-xl)}.input-group label{display:flex;align-items:center;gap:var(--spacing-sm);font-size:1rem;font-weight:600;margin-bottom:var(--spacing-xs);color:var(--text-primary)}.label-icon{font-size:1.1rem}.required-badge{background:#fef2f2;color:#dc2626;font-size:.7rem;font-weight:600;padding:2px 8px;border-radius:9999px;text-transform:uppercase;letter-spacing:.5px}.input-help{font-size:.9rem;color:var(--text-secondary);margin-bottom:var(--spacing-sm);line-height:1.5}.input-group textarea{width:100%;padding:var(--spacing-md);background:var(--bg-input);border:2px solid var(--border-color);border-radius:var(--radius-lg);color:var(--text-primary);font-family:var(--font-family);font-size:.95rem;line-height:1.6;resize:vertical;transition:border-color var(--transition-fast),box-shadow var(--transition-fast)}.input-group textarea::placeholder{color:var(--text-muted)}.input-group textarea:focus{outline:none;border-color:var(--border-focus);box-shadow:0 0 0 3px var(--primary-light)}.input-group textarea.error{border-color:var(--error)}.load-sample-btn{margin-top:var(--spacing-sm);padding:var(--spacing-xs) var(--spacing-md);background:var(--bg-tertiary);border:1px solid var(--border-color);border-radius:var(--radius-md);color:var(--text-secondary);font-size:.85rem;cursor:pointer;transition:all var(--transition-fast)}.load-sample-btn:hover{background:var(--bg-hover);color:var(--text-primary);border-color:var(--primary)}.validation-message{display:flex;align-items:center;gap:var(--spacing-sm);padding:var(--spacing-md);background:#fef2f2;border:1px solid #fecaca;border-radius:var(--radius-md);margin-bottom:var(--spacing-lg);color:#dc2626;font-size:.95rem}.validation-message.hidden{display:none}.validation-icon{font-size:1.2rem}.action-buttons{display:flex;gap:var(--spacing-md)}.primary-btn,.secondary-btn{display:flex;align-items:center;justify-content:center;gap:var(--spacing-sm);padding:var(--spacing-md) var(--spacing-xl);border-radius:var(--radius-lg);font-size:1rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);border:none}.primary-btn{background:var(--primary);color:#fff;flex:1}.primary-btn:hover{background:var(--primary-hover);transform:translateY(-1px);box-shadow:var(--shadow-md)}.primary-btn:disabled{opacity:.6;cursor:not-allowed;transform:none}.secondary-btn{background:var(--bg-tertiary);color:var(--text-secondary);border:1px solid var(--border-color)}.secondary-btn:hover{background:var(--bg-hover);color:var(--text-primary)}.btn-icon{font-size:1.1rem}.results-section{margin-top:var(--spacing-xl);background:var(--bg-primary);border-radius:var(--radius-xl);padding:var(--spacing-xl);border:1px solid var(--border-color);box-shadow:var(--shadow-sm)}.results-section.hidden{display:none}.section-title{font-size:1.5rem;font-weight:600;margin-bottom:var(--spacing-lg);color:var(--text-primary);text-align:center}.loading-state{display:flex;flex-direction:column;align-items:center;padding:var(--spacing-2xl);color:var(--text-secondary)}.loading-state.hidden{display:none}.spinner{width:48px;height:48px;border:3px solid var(--border-color);border-top-color:var(--primary);border-radius:50%;animation:spin 1s linear infinite;margin-bottom:var(--spacing-md)}@keyframes spin{to{transform:rotate(360deg)}}.loading-subtext{font-size:.85rem;color:var(--text-muted);margin-top:var(--spacing-xs)}.error-state{display:flex;flex-direction:column;align-items:center;padding:var(--spacing-xl);text-align:center}.error-state.hidden{display:none}.error-icon{font-size:3rem;margin-bottom:var(--spacing-md)}.error-state p{color:var(--error);margin-bottom:var(--spacing-lg)}.scroll-hint{display:flex;align-items:center;justify-content:center;gap:var(--spacing-md);padding:var(--spacing-md);background:var(--primary-light);border-radius:var(--radius-md);margin-bottom:var(--spacing-lg)}.scroll-hint.hidden{display:none}.scroll-text{font-size:.9rem;color:var(--primary);font-weight:500}.scroll-arrow{display:flex;align-items:center;justify-content:center;width:32px;height:32px;background:var(--primary);color:#fff;border-radius:50%;font-size:1rem;cursor:pointer;transition:all var(--transition-fast);-webkit-user-select:none;user-select:none}.scroll-arrow:hover{background:var(--primary-hover);transform:scale(1.1)}.scroll-arrow:active{transform:scale(.95)}.roadmap-container{overflow-x:auto;padding-bottom:var(--spacing-md);scroll-behavior:smooth}.roadmap{display:flex;gap:var(--spacing-lg);min-width:max-content;padding:var(--spacing-sm)}.semester{min-width:280px;background:var(--bg-tertiary);border-radius:var(--radius-lg);padding:var(--spacing-lg);border:1px solid var(--border-color)}.semester-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:var(--spacing-md);padding-bottom:var(--spacing-md);border-bottom:1px solid var(--border-color)}.semester-name{font-size:1.1rem;font-weight:600;color:var(--text-primary)}.semester-credits{font-size:.85rem;color:var(--text-muted);background:var(--bg-primary);padding:var(--spacing-xs) var(--spacing-sm);border-radius:var(--radius-sm);border:1px solid var(--border-color)}.course-list{display:flex;flex-direction:column;gap:var(--spacing-sm)}.course-card{background:var(--bg-primary);border-radius:var(--radius-md);padding:var(--spacing-md);border:1px solid var(--border-color);transition:all var(--transition-fast);position:relative}.course-card:hover{border-color:var(--primary);box-shadow:var(--shadow-sm)}.course-card.recommended{border-left:3px solid var(--success)}.course-card.suggested{border-left:3px solid var(--accent)}.course-card.conflict{border-left:3px solid var(--warning)}.course-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:var(--spacing-xs)}.course-header-left{display:flex;align-items:center;gap:var(--spacing-sm)}.course-code{font-weight:600;color:var(--text-primary)}.course-badge{font-size:1rem}.course-name{font-size:.9rem;color:var(--text-secondary);margin-bottom:var(--spacing-sm);word-wrap:break-word;overflow-wrap:break-word}.course-meta{display:flex;gap:var(--spacing-md);font-size:.8rem;color:var(--text-muted)}.course-reason{margin-top:var(--spacing-sm);padding-top:var(--spacing-sm);border-top:1px solid var(--border-color);font-size:.85rem;color:var(--text-secondary);font-style:italic;word-wrap:break-word;overflow-wrap:break-word}.legend{display:flex;flex-wrap:wrap;gap:var(--spacing-lg);margin-top:var(--spacing-xl);padding-top:var(--spacing-lg);border-top:1px solid var(--border-color);justify-content:center}.legend.hidden{display:none}.legend-item{display:flex;align-items:center;gap:var(--spacing-sm);color:var(--text-secondary);font-size:.9rem}.legend-icon{font-size:1.1rem}.footer{text-align:center;padding:var(--spacing-xl) 0;margin-top:var(--spacing-xl);color:var(--text-muted);font-size:.9rem}@media (max-width: 768px){.app-container{padding:var(--spacing-md)}.hero{padding:var(--spacing-xl) var(--spacing-md)}.hero h1{font-size:1.75rem}.hero-description{font-size:1rem}.how-it-works{flex-direction:column}.step-arrow{transform:rotate(90deg)}.input-section,.results-section{padding:var(--spacing-lg);border-radius:var(--radius-lg)}.action-buttons{flex-direction:column}.primary-btn,.secondary-btn{width:100%}.semester{min-width:260px}.legend{flex-direction:column;align-items:center;gap:var(--spacing-sm)}.scroll-hint{flex-wrap:wrap;text-align:center}}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--bg-tertiary);border-radius:var(--radius-sm)}::-webkit-scrollbar-thumb{background:var(--border-color);border-radius:var(--radius-sm)}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}:focus-visible{outline:2px solid var(--primary);outline-offset:2px}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.semester{animation:fadeIn .3s ease forwards}.semester:nth-child(1){animation-delay:.1s}.semester:nth-child(2){animation-delay:.2s}.semester:nth-child(3){animation-delay:.3s}.semester:nth-child(4){animation-delay:.4s}.semester:nth-child(5){animation-delay:.5s}.semester:nth-child(6){animation-delay:.6s}