body {
    background-color: antiquewhite;
}

.circle {
    width: 50px;
    height: 50px;
    background: red;
    border-radius: 50%;
    margin-left: auto;
    margin-right: auto;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    position: fixed;
}

input {
    display: block;
    width: 20%;
}

#submit {
    width: 60px;
    margin-top: 10px;
}