:root{--bg: #0f0f13;--surface: #1a1a24;--card: #22223a;--card-hover: #2a2a46;--border: #2e2e48;--accent: #6c63ff;--accent-hover: #7d75ff;--accent-dim: rgba(108, 99, 255, .15);--success: #22c55e;--success-dim: rgba(34, 197, 94, .15);--warning: #f59e0b;--warning-dim: rgba(245, 158, 11, .15);--error: #ef4444;--error-dim: rgba(239, 68, 68, .15);--text-primary: #f0f0f8;--text-secondary: #9999bb;--text-muted: #555570;--radius: 12px;--radius-sm: 8px;--radius-lg: 16px;--shadow: 0 4px 24px rgba(0, 0, 0, .4);--shadow-sm: 0 2px 8px rgba(0, 0, 0, .3);--transition: .18s ease}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;scroll-behavior:smooth}body{font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background-color:var(--bg);color:var(--text-primary);line-height:1.6;min-height:100vh;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}#root{min-height:100vh;display:flex;flex-direction:column}h1,h2,h3,h4,h5,h6{font-weight:700;line-height:1.2;color:var(--text-primary)}h1{font-size:2rem}h2{font-size:1.5rem}h3{font-size:1.25rem}p{color:var(--text-secondary);line-height:1.7}a{color:var(--accent);text-decoration:none;transition:color var(--transition)}a:hover{color:var(--accent-hover);text-decoration:underline}input,textarea,select{font-family:inherit;font-size:1rem;background-color:var(--surface);color:var(--text-primary);border:1.5px solid var(--border);border-radius:var(--radius-sm);padding:.65rem 1rem;width:100%;outline:none;transition:border-color var(--transition),box-shadow var(--transition)}input:focus,textarea:focus,select:focus{border-color:var(--accent);box-shadow:0 0 0 3px 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var(--transition),box-shadow var(--transition),opacity var(--transition);display:inline-flex;align-items:center;justify-content:center;gap:.5rem}button:active{transform:scale(.97)}button:disabled{opacity:.5;cursor:not-allowed;transform:none}.btn-primary{background:var(--accent);color:#fff}.btn-primary:hover:not(:disabled){background:var(--accent-hover);box-shadow:0 4px 15px #6c63ff66}.btn-secondary{background:var(--card);color:var(--text-primary);border:1.5px solid var(--border)}.btn-secondary:hover:not(:disabled){background:var(--card-hover)}.btn-success{background:var(--success);color:#fff}.btn-success:hover:not(:disabled){background:#16a34a;box-shadow:0 4px 15px #22c55e4d}.btn-danger{background:var(--error);color:#fff}.btn-danger:hover:not(:disabled){background:#dc2626;box-shadow:0 4px 15px #ef44444d}.btn-ghost{background:transparent;color:var(--text-secondary);border:1.5px solid transparent}.btn-ghost:hover:not(:disabled){background:var(--card);color:var(--text-primary);border-color:var(--border)}.btn-large{padding:1rem 2.5rem;font-size:1.1rem;border-radius:var(--radius)}.btn-full{width:100%}.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem;transition:border-color var(--transition),box-shadow var(--transition)}.card:hover{border-color:var(--accent);box-shadow:0 0 0 1px var(--accent-dim),var(--shadow-sm)}.container{max-width:1100px;margin:0 auto;padding:0 1.5rem}.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-1{gap:.5rem}.gap-2{gap:1rem}.gap-3{gap:1.5rem}.gap-4{gap:2rem}.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:1rem}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem}.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:1rem}.badge{display:inline-flex;align-items:center;padding:.2rem .65rem;border-radius:100px;font-size:.75rem;font-weight:600;text-transform:uppercase;letter-spacing:.04em}.badge-new{background:#9696b426;color:#99b}.badge-learning{background:#3b82f626;color:#60a5fa}.badge-reviewing{background:var(--warning-dim);color:var(--warning)}.badge-familiar{background:#8b5cf626;color:#a78bfa}.badge-mastered{background:var(--success-dim);color:var(--success)}::-webkit-scrollbar{width:8px}::-webkit-scrollbar-track{background:var(--surface)}::-webkit-scrollbar-thumb{background:var(--border);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes pulse{0%,to{opacity:1}50%{opacity:.6}}.animate-fadeIn{animation:fadeIn .25s ease}.animate-slideUp{animation:slideUp .3s 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var(--success-dim),var(--shadow)}.session-card.slow-correct{border-color:var(--warning);box-shadow:0 0 0 1px var(--warning-dim),var(--shadow)}.session-card.incorrect{border-color:var(--error);box-shadow:0 0 0 1px var(--error-dim),var(--shadow)}.german-word{font-size:3rem;font-weight:900;color:var(--text-primary);margin-bottom:2rem;letter-spacing:-.02em}.progress-bar-container{width:100%;background:var(--surface);border-radius:100px;height:6px;margin-bottom:2rem;overflow:hidden}.progress-bar-fill{height:100%;background:var(--accent);border-radius:100px;transition:width .4s ease}.session-timer{font-size:1rem;color:var(--text-muted);font-variant-numeric:tabular-nums;margin-bottom:1.5rem;font-weight:600}.session-input-row{display:flex;gap:.75rem;margin-bottom:1.25rem}.session-input-row input{flex:1;font-size:1.1rem;padding:.85rem 1.1rem;border-radius:var(--radius-sm)}.feedback-result{font-size:1.5rem;font-weight:800;margin-bottom:.75rem}.feedback-result.correct{color:var(--success)}.feedback-result.incorrect{color:var(--error)}.feedback-result.slow{color:var(--warning)}.feedback-answer{font-size:1rem;color:var(--text-secondary);margin-bottom:1.25rem}.feedback-answer strong{color:var(--text-primary)}.feedback-time{font-size:.875rem;color:var(--text-muted);margin-bottom:1.5rem}.intro-card .english-translation{font-size:1.4rem;color:var(--accent);font-weight:600;margin-bottom:1rem}.intro-card .intro-badge{display:inline-block;background:var(--accent-dim);color:var(--accent);padding:.2rem .75rem;border-radius:100px;font-size:.8rem;font-weight:700;text-transform:uppercase;letter-spacing:.06em;margin-bottom:1.5rem}.session-counter{font-size:.875rem;color:var(--text-muted);margin-bottom:1.5rem}.complete-card{text-align:center}.complete-card h2{font-size:2rem;margin-bottom:.5rem}.complete-stats{display:flex;justify-content:center;gap:2rem;margin:2rem 0;flex-wrap:wrap}.complete-stat{text-align:center}.complete-stat .value{font-size:2rem;font-weight:800;color:var(--accent)}.complete-stat .label{font-size:.8rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.05em;font-weight:600}.table-wrapper{overflow-x:auto;border-radius:var(--radius);border:1px solid var(--border)}table{width:100%;border-collapse:collapse;font-size:.9rem}thead th{background:var(--surface);color:var(--text-muted);text-transform:uppercase;font-size:.75rem;font-weight:600;letter-spacing:.06em;padding:.75rem 1rem;text-align:left;border-bottom:1px solid var(--border);white-space:nowrap}tbody tr{border-bottom:1px solid var(--border);transition:background var(--transition)}tbody tr:last-child{border-bottom:none}tbody tr:hover{background:var(--surface)}tbody td{padding:.75rem 1rem;color:var(--text-secondary)}tbody td:first-child{color:var(--text-primary);font-weight:600}.chart-section{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem;margin-bottom:2rem}.chart-card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem}.chart-card h3{font-size:1rem;margin-bottom:1rem;color:var(--text-secondary)}.pagination{display:flex;align-items:center;justify-content:center;gap:.5rem;margin-top:1.5rem}.pagination button{padding:.4rem .9rem;font-size:.875rem;background:var(--card);color:var(--text-secondary);border:1px solid var(--border)}.pagination button.active{background:var(--accent);color:#fff;border-color:var(--accent)}.pagination button:hover:not(:disabled):not(.active){background:var(--card-hover);color:var(--text-primary)}.settings-section{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:1.75rem;margin-bottom:1.5rem}.settings-section h2{font-size:1.1rem;margin-bottom:1.25rem;padding-bottom:.75rem;border-bottom:1px solid var(--border)}.settings-row{display:flex;align-items:center;justify-content:space-between;gap:1rem;margin-bottom:1.25rem}.settings-row:last-child{margin-bottom:0}.settings-label{flex:1}.settings-label .label-title{font-weight:600;color:var(--text-primary);font-size:.95rem}.settings-label .label-desc{font-size:.8rem;color:var(--text-muted);margin-top:.15rem}.danger-zone{border-color:#ef44444d}.danger-zone h2{color:var(--error)}.filter-bar{display:flex;gap:.75rem;margin-bottom:1.25rem;flex-wrap:wrap}.filter-bar input{flex:1;min-width:200px}.filter-bar select{width:auto;min-width:160px}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0009;display:flex;align-items:center;justify-content:center;z-index:1000;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);animation:fadeIn .15s ease}.modal{background:var(--card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:2rem;max-width:400px;width:90%;box-shadow:var(--shadow);animation:slideUp .2s ease}.modal h3{margin-bottom:.75rem}.modal p{margin-bottom:1.5rem;font-size:.95rem}.modal-actions{display:flex;gap:.75rem;justify-content:flex-end}@media (max-width: 768px){.grid-4,.grid-3{grid-template-columns:repeat(2,1fr)}.chart-section{grid-template-columns:1fr}.session-card{padding:2rem 1.5rem}.german-word{font-size:2.2rem}.navbar-links{display:none}.complete-stats{gap:1.25rem}.stats-grid{grid-template-columns:repeat(2,1fr)}}@media (max-width: 480px){.grid-4,.grid-3,.grid-2{grid-template-columns:1fr}.stats-grid{grid-template-columns:1fr 1fr}h1{font-size:1.5rem}.auth-card{padding:1.75rem 1.25rem}}