.question-card{max-width:800px;margin:0 auto;padding:20px;border-radius:10px;background-color:#f8f9fa;box-shadow:0 2px 10px #0000001a}.topic-badge{display:inline-block;padding:5px 10px;background-color:#007bff;color:#fff;border-radius:20px;font-size:.8rem;margin-bottom:15px}.question-text{margin-bottom:20px;color:#333}.options-container{display:flex;flex-direction:column;gap:10px;margin-bottom:20px}.option-button{padding:12px;border:1px solid #ddd;border-radius:5px;background-color:#fff;cursor:pointer;text-align:left;transition:all .2s}.option-button:hover{background-color:#f0f0f0}.option-button.selected{border-color:#007bff;background-color:#e7f1ff}.try-again-button{padding:12px 24px;background-color:#28a745;color:#fff;border:none;border-radius:5px;cursor:pointer;font-weight:700;transition:all .2s}.try-again-button:hover{background-color:#218838}.option-button.correct{border-color:#28a745;background-color:#d4edda}.option-button.incorrect{border-color:#dc3545;background-color:#f8d7da}.check-button,.next-button{padding:10px 20px;background-color:#007bff;color:#fff;border:none;border-radius:5px;cursor:pointer;font-size:1rem}.check-button:hover,.next-button:hover{background-color:#0056b3}.answer-section{margin-top:20px;padding:15px;background-color:#f1f8ff;border-radius:5px}.explanation,.mnemonic{margin-bottom:15px}.app-container{max-width:1000px;margin:0 auto;padding:20px}.question-list-container{min-height:300px;display:flex;flex-direction:column;justify-content:center}.loading,.error,.no-questions{text-align:center;padding:20px;font-size:1.2rem}.error{color:#dc3545}.progress-indicator{text-align:center;margin-top:20px;color:#666;font-size:.9rem}