.gallery {
    display: grid;
    max-width: 1200px;
    margin: 0 auto;
    grid-template-columns: repeat(auto-fill, minmax(min(20rem, 100%), 1fr));
    justify-content: space-between;
    grid-gap: 20px;
}

.panel H3,h4 {
    text-align: center;
}

.panel img {
    width: 100%;

}

footer {
    position: relative;
}