header, footer {
    background: black;
    color: white;
}

img {
    max-width: 100%;
}

section.headline {
    height: 500px;
    background: url(images/istockphoto-955760380-1024x1024.jpg) center center no-repeat;
    background-size: cover;
}

section.camouflage {
    background: green url(https://images.ctfassets.net/79wlha8q128n/4HRCdtMMca8R3RurYj187V/983921094792b204e4a7981c5d6f1881/Background-Camo-Woodland.svg);
}

.img-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}