body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 20px;
    background-color: #f5f5f5;
    color: #333;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
}

h1 {
    color: #2c3e50;
    text-align: center;
    margin-bottom: 30px;
}

h2 {
    color: #2c3e50;
    border-bottom: 2px solid #3498db;
    padding-bottom: 10px;
    margin-top: 30px;
}

.student-info {
    margin-bottom: 20px;
    padding: 20px;
    background-color: #f8f9fa;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.student-info label {
    font-weight: bold;
    margin-right: 10px;
    font-size: 18px;
}

.student-info input {
    padding: 10px;
    border: 2px solid #ddd;
    border-radius: 6px;
    width: 300px;
    margin-right: 10px;
    font-size: 16px;
}

#start-btn {
    padding: 10px 20px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
    transition: all 0.3s;
}

#start-btn:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
}

.error-message {
    color: #e74c3c;
    margin-top: 10px;
    font-weight: bold;
    display: none;
}

.exercise-container {
    display: none;
    margin-top: 20px;
}

.student-welcome {
    text-align: center;
    margin-bottom: 30px;
    padding: 15px;
    background-color: #e8f4fc;
    border-radius: 8px;
}

.student-welcome h2 {
    color: #2c3e50;
    border-bottom: none;
}

.exercise {
    display: none;
    margin-bottom: 25px;
    padding: 20px;
    border: 2px solid #eee;
    border-radius: 8px;
    background-color: #f8f9fa;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.exercise.active {
    display: block;
    animation: fadeIn 0.5s ease-in-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.answer-input {
    margin-top: 20px;
}

.answer-input label {
    display: block;
    margin-bottom: 15px;
    font-size: 17px;
}

.answer-input input {
    padding: 10px;
    border: 2px solid #ddd;
    border-radius: 6px;
    width: 100%;
    max-width: 400px;
    margin-left: 10px;
    font-size: 16px;
    transition: border 0.3s;
}

.answer-input input:focus {
    border-color: #3498db;
    outline: none;
}

.navigation-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 30px;
    gap: 15px;
}

.navigation-buttons button {
    padding: 12px 25px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
    transition: all 0.3s;
    flex: 1;
}

.navigation-buttons button:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
}

.navigation-buttons button:disabled {
    background-color: #95a5a6;
    cursor: not-allowed;
    transform: none;
}

#check-answer {
    background-color: #2ecc71;
}

#check-answer:hover {
    background-color: #27ae60;
}

#check-answer:disabled {
    background-color: #bdc3c7;
}

.exercise-feedback {
    margin-top: 25px;
    padding: 20px;
    border-radius: 8px;
    display: none;
    animation: fadeIn 0.5s ease-in-out;
    background-color: #f8f9fa;
    border-left: 5px solid #3498db;
}

#exercise-result {
    font-weight: bold;
    margin: 0;
    font-size: 17px;
    line-height: 1.6;
}

.correct {
    color: #27ae60;
}

.incorrect {
    color: #e74c3c;
}

.solution {
    color: #7f8c8d;
    font-style: italic;
    margin-top: 10px;
    padding: 10px;
    background-color: #f1f1f1;
    border-radius: 5px;
    border-left: 3px solid #3498db;
}

.results {
    margin-top: 20px;
    padding: 25px;
    background-color: #f8f9fa;
    border-radius: 10px;
    display: none;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

#final-score-message {
    font-weight: bold;
    font-size: 20px;
    color: #2c3e50;
    margin-bottom: 20px;
}

#score-value {
    color: #3498db;
    font-size: 24px;
}

#feedback-message {
    font-size: 18px;
    margin: 20px 0;
    line-height: 1.6;
}

#detailed-results {
    margin-top: 20px;
}

.detail-item {
    margin-bottom: 15px;
    padding: 15px;
    border-radius: 8px;
    background-color: #ecf0f1;
}

.detail-item h3 {
    margin-top: 0;
    color: #2c3e50;
}

.detail-correct {
    border-left: 5px solid #27ae60;
}

.detail-incorrect {
    border-left: 5px solid #e74c3c;
}

#restart-btn {
    padding: 12px 25px;
    background-color: #e67e22;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
    margin-top: 20px;
    transition: all 0.3s;
    width: 100%;
}

#restart-btn:hover {
    background-color: #d35400;
    transform: translateY(-2px);
}

/* Añadir al final del archivo CSS */

.progress-container {
    width: 100%;
    background-color: #f1f1f1;
    border-radius: 10px;
    margin: 20px 0;
    box-shadow: inset 0 1px 3px rgba(0,0,0,0.2);
}

.progress-bar {
    height: 20px;
    background-color: #3498db;
    border-radius: 10px;
    width: 0%;
    transition: width 0.5s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    font-size: 12px;
}

.progress-text {
    margin-top: 5px;
    text-align: center;
    font-weight: bold;
    color: #2c3e50;
}