Två sätt! ✌️
.selector {
background-image: url("image_location/filename.jpg");
}CSS properties
background-color:
background-image:
background-position:
background-size:
background-repeat:
<color>
url() / gradient
left / center / right / top / bottom
auto / cover / contain
repeat /no-repeat / repeat-x / repeat-y
Även background-attachment, background-origin, background-clip ....
Interaktiv guide