* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

canvas {
    /* border: 1px solid #000; */
}

.center {
    position: absolute;
    top:50%;
    left:50%;
    transform: translate(-50%, -50%);
}

.ui {
    display: none;
    background: #ccc;
    padding: 50px;
    border-radius: 10px;
}

.ui input {
    width: 100%;
    height: 2rem;
    border-radius: 5px;
    border: none;
    padding: 10px;
    margin-top: 20px;
}

.ui input[type="submit"] {
    padding: 0px;
}