#tahvel{
    background-color: lightblue;
    width: 50%;
    height: 35%;
}
h1{
    border-radius: 200px;
    border: solid 3pt black;
    background-color: aqua;
    font-family: "Times New Roman";
    text-align: center;
}
input[type=button]{
    background-color: green;
    color: black;
    padding: 15px 20px;
    border:0;
}
input[type=button]:hover{
    background-color: greenyellow;
}