body {
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #e0f7fa, #b2ebf2);
    margin: 0;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container {
    background-color: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 500px;
}

.header-container {
    margin-bottom: 20px;
}

h1 {
    color: #00796b;
    margin-bottom: 20px;
    font-size: 1.8em;
    text-align: center;
}

.student-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 15px;
    background-color: #e8f5e9;
    padding: 15px;
    border-radius: 10px;
    border: 2px solid #00796b;
}

.input-group {
    flex: 1;
    margin-bottom: 0;
}

label {
    display: block;
    margin-bottom: 5px;
    color: #00796b;
    font-weight: bold;
    font-size: 0.9em;
}

input {
    width: 100%;
    padding: 10px;
    border: 2px solid #b2dfdb;
    border-radius: 8px;
    font-size: 1em;
    box-sizing: border-box;
    transition: border 0.3s;
}

input:focus {
    border-color: #00796b;
    outline: none;
}

.score-display {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 80px;
    padding: 8px 12px;
    background-color: #00796b;
    border-radius: 8px;
    color: white;
}

.score-label {
    font-size: 0.8em;
    font-weight: bold;
    margin-bottom: 3px;
}

.score-value {
    font-size: 1.5em;
    font-weight: bold;
}

.exercise-box {
    background-color: #f5f5f5;
    padding: 20px;
    border-radius: 10px;
}

#proportionEquation {
    margin: 20px 0;
    font-size: 28px;
    text-align: center;
}

.button-container {
    display: flex;
    justify-content: space-between;
    gap: 15px;
    margin-top: 20px;
}

button {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s;
}

#generateExercise {
    background-color: #00796b;
    color: white;
}

#generateExercise:hover {
    background-color: #00695c;
}

#checkAnswer {
    background-color: #ff9800;
    color: white;
}

#checkAnswer:hover {
    background-color: #f57c00;
}

button:disabled {
    background-color: #bdbdbd !important;
    cursor: not-allowed;
}

#feedback {
    margin-top: 20px;
    padding: 10px;
    border-radius: 5px;
    font-weight: bold;
    text-align: center;
}

.correct {
    color: #388e3c;
    background-color: #e8f5e9;
}

.incorrect {
    color: #d32f2f;
    background-color: #ffebee;
}

.info {
    color: #1976d2;
    background-color: #e3f2fd;
}