*{box-sizing:border-box}body{background:linear-gradient(135deg,#48dbfb,#0abde3);color:#fff;font-family:Arial,sans-serif;margin:0;padding:0;min-height:100vh}main{padding:2rem 1rem;max-width:1000px;margin:0 auto}.quiz-container{background:#fffffffa;border-radius:20px;padding:2.5rem;box-shadow:0 10px 40px #0000004d;color:#333}.quiz-nav-links{display:flex;gap:1rem;justify-content:center;margin-bottom:1.5rem;flex-wrap:wrap}.nav-link-btn{display:inline-flex;align-items:center;gap:.5rem;padding:.8rem 1.5rem;border:2px solid #dee2e6;border-radius:50px;font-size:1rem;font-weight:600;cursor:pointer;transition:all .3s ease;text-decoration:none;background:#fff;color:#495057;box-shadow:0 2px 8px #0000001a}.nav-link-btn:hover{transform:translateY(-2px);box-shadow:0 4px 12px 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#667eea66}.question-card{background:#f8f9fa;border:3px solid #e0e0e0;border-radius:15px;padding:1.8rem;margin-bottom:1.8rem;transition:all .3s ease}.question-card:hover{box-shadow:0 5px 15px #00000026;transform:translateY(-2px)}.question-card.correct{background:#d4edda;border-color:#28a745}.question-card.incorrect{background:#f8d7da;border-color:#dc3545}.question-number{display:inline-block;background:#48dbfb;color:#fff;padding:.4rem 1rem;border-radius:20px;font-weight:700;font-size:1rem;margin-bottom:.8rem}.question-text{font-size:1.6rem;font-weight:700;color:#333;margin:1.2rem 0;letter-spacing:.5px}.options{display:grid;grid-template-columns:repeat(2,1fr);gap:1.2rem;margin-top:1.5rem}.option-label{display:block;background:#fff;border:3px solid #dee2e6;border-radius:12px;padding:1.3rem;cursor:pointer;transition:all .3s ease;text-align:center;font-size:1.4rem;font-weight:600}.option-label:hover{background:#e7f3ff;border-color:#2196f3;transform:scale(1.05)}.option-input{display:none}.option-input:checked+.option-label{background:#2196f3;color:#fff;border-color:#2196f3;box-shadow:0 4px 15px #2196f366}.option-label.correct-answer{background:#28a745;color:#fff;border-color:#28a745}.option-label.wrong-answer{background:#dc3545;color:#fff;border-color:#dc3545}.option-input:checked+.option-label.correct-answer{background:#43a047;color:#fff;border-color:#43a047}.option-input:checked+.option-label.wrong-answer{background:#e53935;color:#fff;border-color:#e53935;box-shadow:0 4px 15px #e5393566}.button-group{display:flex;gap:1rem;justify-content:center;margin-top:2rem;flex-wrap:wrap}.action-button{padding:1.2rem 2.5rem;border:none;border-radius:50px;font-size:1.3rem;font-weight:700;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #0003;min-width:200px}.check-button{background:linear-gradient(135deg,#48dbfb,#0abde3);color:#fff}.reset-button{background:linear-gradient(135deg,#f093fb,#f5576c);color:#fff}.action-button:hover{transform:translateY(-3px);box-shadow:0 6px 20px #0000004d}.action-button:active{transform:translateY(0)}.score-container{background:#f8f9fa;border-radius:15px;padding:2rem;margin-top:2rem;text-align:center;border:3px solid #48dbfb}.score-display{font-size:3.5rem;font-weight:700;margin:1rem 0}.score-excellent{color:#28a745}.score-good{color:#17a2b8}.score-fair{color:#ffc107}.score-needs-practice{color:#dc3545}.score-message{font-size:1.5rem;margin:1rem 0;color:#666;font-weight:600}.hidden{display:none!important}.alert-message{background:#fff3cd;color:#856404;border:2px solid #ffc107;border-radius:10px;padding:1rem;margin-top:1rem;text-align:center;font-size:1.2rem;font-weight:600}.modal-overlay{position:fixed;inset:0;background:#000000b3;display:flex;align-items:center;justify-content:center;z-index:1000}.modal-content{background:#fff;border-radius:20px;padding:2.5rem;max-width:500px;margin:1rem;box-shadow:0 10px 40px #0000004d;text-align:center}.modal-title{color:#48dbfb;font-size:1.8rem;margin-bottom:1rem;font-weight:700}.modal-text{color:#666;font-size:1.1rem;margin-bottom:1.5rem;line-height:1.6}.modal-buttons{display:flex;gap:1rem;justify-content:center;flex-wrap:wrap}.modal-button{padding:1rem 2rem;border:none;border-radius:50px;font-size:1.2rem;font-weight:700;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #0003;min-width:150px}.modal-button.resume{background:linear-gradient(135deg,#28a745,#20c997);color:#fff}.modal-button.start-fresh{background:linear-gradient(135deg,#48dbfb,#0abde3);color:#fff}.modal-button:hover{transform:translateY(-2px);box-shadow:0 6px 20px #0000004d}.progress-indicator{background:#e7f3ff;color:#2196f3;border:2px solid #2196F3;border-radius:10px;padding:.8rem 1.5rem;margin-bottom:1.5rem;text-align:center;font-size:1.1rem;font-weight:600;display:flex;align-items:center;justify-content:center;gap:.5rem}.progress-indicator .icon{font-size:1.3rem}.retry-button{background:linear-gradient(135deg,#ff9800,#ff5722);color:#fff}.retry-button:hover{transform:translateY(-3px);box-shadow:0 6px 20px #ff980066}.clear-progress-btn{background:linear-gradient(135deg,#dc3545,#c82333);color:#fff;padding:.8rem 1.5rem;border:none;border-radius:50px;font-size:1rem;font-weight:700;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #dc35454d;margin-top:1rem}.clear-progress-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px #dc354580}.quiz-info{background:#f8f9fa;border:2px solid #48dbfb;border-radius:15px;padding:1.5rem;margin-bottom:1rem;text-align:center}.quiz-info-title{font-size:1.5rem;font-weight:700;color:#48dbfb;margin-bottom:.5rem}.quiz-info-set{font-size:1.3rem;font-weight:600;color:#0abde3;margin-bottom:.5rem}@media(max-width:768px){main{padding:1rem .5rem}.quiz-container{padding:1.5rem 1rem}h1{font-size:2rem}.options{grid-template-columns:1fr}.set-selector{gap:.3rem}.set-tab{padding:.8rem 1rem;font-size:1rem}.question-text{font-size:1.3rem}.option-label{font-size:1.2rem;padding:1rem}.action-button{font-size:1.1rem;padding:1rem 2rem;min-width:150px}.nav-link-btn{font-size:.9rem;padding:.7rem 1.2rem}}