body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: #f4f4f9;
    margin: 0;
    padding: 20px;
}

h1 {
    color: #333;
    margin-bottom: 20px;
}

.button-container {
    margin: 20px 0;
}

button {
    background-color: #007bff;
    color: white;
    border: none;
    padding: 10px 20px;
    margin: 5px;
    cursor: pointer;
    border-radius: 5px;
    font-size: 16px;
}

button:hover {
    background-color: #0056b3;
}

#nodes {
    max-width: 600px;
    margin: 20px auto;
}

.node {
    background-color: white;
    padding: 10px;
    margin: 5px 0;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    text-align: left;
}