body {
        font-family: 'Segoe UI', sans-serif;
        background: #f0f4f8;
        margin: 0;
        padding: 40px;
    }
    
    .container {
        background: #ffffff;
        border-radius: 10px;
        padding: 30px;
        max-width: 600px;
        margin: auto;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    }
    
    h1 {
        text-align: center;
        margin-bottom: 20px;
    }
    
    form label {
        display: block;
        margin-top: 15px;
    }
    
    input {
        padding: 8px;
        width: 100%;
        margin-top: 5px;
        border-radius: 4px;
        border: 1px solid #ccc;
    }
    
    button {
        margin-top: 20px;
        padding: 10px;
        width: 100%;
        background: #0078D7;
        color: white;
        border: none;
        border-radius: 4px;
        font-weight: bold;
        cursor: pointer;
    }
    
    button:hover {
        background: #005fa3;
    }
    
    .card {
        margin-top: 30px;
        padding: 20px;
        border-radius: 6px;
        color: #fff;
    }
    
    .card.cluster-0 {
        background-color: #4a90e2;
    }
    .card.cluster-1 {
        background-color: #50e3c2;
    }
    .card.cluster-2 {
        background-color: #f5a623;
    }
    
    .hidden {
        display: none;
    }
    
    #clusterChart {
        margin-top: 40px;
    }