When 1 px border is added to div, Div size increases, Don't want to do that

Question

On click I am adding, 1px border to div, so Div size increases by 2px X 2px. I dont want to get div size increased. Is there any simple way to do so?

Answer 1

Sometimes you don't want height or width to be affected without explicitly setting either. In that case, I find it helpful to use pseudo elements.

.border-me {
    position: relative;
}

.border-me::after {
    content: "";
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    border: solid 1px black;
}

You can also do a lot more with the pseudo element so this is a pretty powerful pattern.