body {
    margin: 0;
    background-image: url("bg.png");
    background-color: #A8A8A8;
}

.center {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

img {
    height: auto;
    max-width: 100%;
}

/*.img-border {*/
/*    height: auto;*/
/*    max-width: 100%;*/
/*}*/