body {
    font-family: 'Roboto', sans-serif;
    text-align: center;
    margin: 0;
    padding: 0;
    background-color: #f4f4f9;
    color: #333;
}

h1 {
    font-size: 2.5rem;
    margin: 20px 0;
    color: #4a90e2;
}

#controls {
    margin: 20px;
    display: flex;
    justify-content: center;
    gap: 10px;
}

#controls button {
    background-color: #4a90e2;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

#controls button:hover {
    background-color: #357ab8;
}

canvas {
    border: 2px solid #4a90e2;
    display: block;
    margin: 20px auto;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

#add-edge-dialog {
    display: none; /* Ensure the add edge dialog is hidden by default */
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: white;
    border: 1px solid #ddd;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    z-index: 1000;
}

#add-edge-dialog h3 {
    margin-top: 0;
    color: #4a90e2;
}

#add-edge-dialog label {
    display: block;
    margin: 10px 0 5px;
    font-weight: bold;
}

#add-edge-dialog input, #add-edge-dialog select {
    width: 100%;
    padding: 10px;
    margin-bottom: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

#add-edge-dialog button {
    background-color: #4a90e2;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

#add-edge-dialog button:hover {
    background-color: #357ab8;
}