html, body, iframe {
     margin: 0;
     padding: 0;
     width: 100%;
     height: 95%;
 }

button {
    font-size: 18px;
    font-weight: bold;
    border: none;
    width: 30%;
    border-radius: 10px;
    background: rgb(103, 58, 183);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    position: center;
    margin-left: auto;
    margin-right: auto;
    padding: 10px;
}