#kalk1, #kalk2, #kalk3{
    width: 400px;
    height: 200px;
    border: 1pt solid blueviolet;
    border-radius: 10px;
    background-color: mediumpurple;
    text-align: center;
}
input[type="number"] {
    width: 60px;
    height: 30px;
    border: 1px solid #ccc;
    background-color: greenyellow;
    appearance: none;
}