Discussion on: Fix Collapsing in CSS3

[Temani Afif]

For the empty div I would add the following CSS:

div::before {
    content: "";
    display: inline-block;
}

This will trigger the creation of a linebox without having to add a space inside your div.

[Abdelrahman AbouDeghedy]

Thanks!

[Temani Afif]

and in case you are sure the div is empty you can do

div:empty::before {
    content: "";
    display: inline-block;
}