Animating max-height with CSS transitions

Madd0g picture Madd0g · Apr 16, 2013 · Viewed 90.2k times · Source

I want to create an expand/collapse animation that's powered only by classnames (javascript is used to toggle the classnames).

I'm giving one class max-height: 4em; overflow: hidden;

and the other max-height: 255em; (I also tried the value none, which didn't animate at all)

this to animate: transition: max-height 0.50s ease-in-out;

I used CSS transitions to switch between them, but the browser seems to be animating all those extra em's, so it creates a delay in the collapse effect.

Is there a way of doing it (in the same spirit - with css classnames) that doesn't have that side-effect (I can put a lower pixel count, but that obviously has drawbacks, since it might cut off legit text - that's the reason for the big value, so it doesn't cut off legit long text, only ridiculously long ones)

See the jsFiddle - http://jsfiddle.net/wCzHV/1/ (click on the text container)

Answer

egor.xyz picture egor.xyz · Aug 23, 2016

Fix delay solution:

Put cubic-bezier(0, 1, 0, 1) transition function for element.

scss

.text {
  overflow: hidden;
  max-height: 0;
  transition: max-height 0.5s cubic-bezier(0, 1, 0, 1);

  &.full {
    max-height: 1000px;
    transition: max-height 1s ease-in-out;
  }
}

css

.text {
  overflow: hidden;
  max-height: 0;
  transition: max-height 0.5s cubic-bezier(0, 1, 0, 1);
}

.text.full {
  max-height: 1000px;
  transition: max-height 1s ease-in-out;
}