.gallery {
    margin: 10px 50px;
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    grid-gap: 10px;
    grid-auto-flow: dense;
}

.gallery img {
    width: 230px;
    padding: 5px;
    filter: grayscale(90%);
    -webkit-filter: grayscale(90%);
    transition: 1s;
    -webkit-transition: 1s;
    -moz-transition: 1s;
    -ms-transition: 1s;
    -o-transition: 1s;
}

.gallery img:hover {
    filter: grayscale(0);
    -webkit-filter: grayscale(0);
    transform: scale(1.1);
    -webkit-transform: scale(1.1);
    -moz-transform: scale(1.1);
    -ms-transform: scale(1.1);
    -o-transform: scale(1.1);
}