how fade in a flex box?

Question

How do I get a flex box to not be part of the page until I fade it in? I used to do this with \'display: 0;\' and then use jquery .fadeIn(). But now if I set display to 0, when

Answer 1

You can set the opacity as 0 and animate:

$('#popupContainer').animate({
    opacity: 1
}, 'fast');