.summation-game-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.game-settings {
    margin-bottom: 20px;
    padding: 15px;
    background-color: #fff;
    border-radius: 8px;
}

.setting-group {
    margin-bottom: 15px;
}

.setting-group label {
    display: inline-block;
    width: 200px;
    font-weight: bold;
}

.game-button {
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 10px 0;
    cursor: pointer;
    border-radius: 5px;
    transition: background-color 0.3s;
}

.game-button:hover {
    background-color: #45a049;
}

#number-display {
    font-size: 24px;
    text-align: center;
    min-height: 50px;
    padding: 20px;
    background-color: #fff;
    border-radius: 8px;
    margin-bottom: 20px;
}

#result-form {
    text-align: center;
    margin-bottom: 20px;
}

#user-answer {
    padding: 10px;
    font-size: 18px;
    width: 200px;
    margin-right: 10px;
}

#game-result {
    font-size: 20px;
    text-align: center;
    padding: 15px;
    border-radius: 8px;
}

.correct {
    background-color: #dff0d8;
    color: #3c763d;
}

.incorrect {
    background-color: #f2dede;
    color: #a94442;
}