body {
    padding: 0;
    margin: 0;   
    font-family:'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: whitesmoke;
    background-size: cover;
    color: #333;
}

#container {
    margin: 2px 5px 2px 5px;
    border: 1px dashed #AAA;
    align-items: center;
    display:inline-flex;
    background-color: white;
}

#uniek {
    background-color: darkred;
    color: salmon;
}

.vierkant {
    width: 200px;
    height: 200px;
    margin: 20px;
    background-color: chocolate;
    padding: 10px;
}

#uniek h2 {
    text-transform: uppercase;
    color: cornsilk;
}