#banner{
    display: flex;
}
#banner a img.banner-show {
    height: auto;
    width: auto;
    justify-content: center;
}

#banner a img.banner-hide {
    height: 0;
    width: 0;
    opacity: 0;
    visibility: hidden;
    transition: opacity 1s, visibility 0s 1s; 
    display: none;
}

#banner > a{
   
    display: block;
    
}