I created some div bars with HTML & CSS that look like this:

and I wanted functionality such that when I click any of the gray div bars, the rest of the divs make room for a hidden blue div to appear below the bar. For example:

Then, clicking the bar again will make the hidden div disappear and make the space between the divs collapse back to what it was previously. I solved this problem using jQuery. For example:

$(function() {
    $(".bar").click(function() {
        $(this).next(".hidden-data").toggle();
    });
});

This basically says, when a bar is clicked, toggle visibility of the next div.

Here is a codepen that demonstrates this working, which also shows the HTML and CSS used. Notice that the hidden div appears instantly when a bar is clicked:

See the Pen Click bar to show hidden data with jQuery (small bars) by Chris Nielsen (@Chris_Nielsen) on CodePen.0

 

In order to make the expanding divs animate smoothly, I added a CSS keyframes animation. For example:

.hidden-data {
  display: none;  
  width: 350px;
  height: 70px;
  border: solid 1px #aaa;
  border-radius: 8px;
  padding: 20px;
  font-size: 24px;
  margin: 15px;
  background-color: #e6eeff;
  z-index: 1;
  animation-name: slideDown;
  animation-duration: .4s;
  animation-fill-mode: forwards;
}

@keyframes slideDown {
    0% { height: 0px; }
    100% { height: 70px; }
}

 

Here is how the final result animates (codepen):

See the Pen Click bar to show hidden data with jQuery (small bars) with CSS keyframes by Chris Nielsen (@Chris_Nielsen) on CodePen.0

 

For more information about jQuery .next(), see:
https://www.w3schools.com/jquery/traversing_next.asp
https://api.jquery.com/next/

For more information about jQuery .toggle(), see:
https://www.w3schools.com/jquery/eff_toggle.asp
https://api.jquery.com/toggle/

For more information about CSS keyframes, see:
https://www.w3schools.com/cssref/css3_pr_animation-keyframes.asp