Shrink div elements while adding new ones

Question

I'll try to explain it as best as I can. I want to apply this principle to my own.

Tab Add Example

As you can see I'm adding 'tabs' to tab bar. When I add enough tabs to fill the whole tab bar, and I keep adding more, those tabs basically resize to fit the div. I don't want them to expand the div or to use the scroll bar to move among them. I want them to shrink within the div. You can see the exact example on the GIF I linked.

It should also behave the same on window resize.

Window Resize Example

Do you have any ideas on how to achieve this? I tried with JQuery but it was too much 'hard coding', it wouldn't work on resize, nor different screen resolutions.

HTML I want to apply:

<div class="l_tabs">
 <div>
  <ul id="myTab1" class="nav nav-tabs bordered">
   <li class="tab-add"></li>
   <li class="contentTab"></li>
   <li class="contentTab"></li>
   <li class="contentTab"></li>
   <li class="contentTab"></li>
  </ul>
 </div>
</div>

When I add new tab it adds this
<li class="contentTab"></li>

JSFiddle

Any suggestions?

Answer 1

You can do this with Flexbox, you just need to set flex-basis

$(".add").click(function() {
  $(".tabs").append('<li class="tab">Lorem ipsum</li>');
})

$('.remove').click(function() {
  $('.tab').last().remove();
})

.tabs {
  display: flex;
  list-style: none;
  padding: 0;
}
.tab {
  border: 1px solid black;
  flex-basis: 200px;
  text-align: center;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<ul class="tabs">
  <li class="tab">Lorem ipsum</li>
</ul>

<button class="add">Add Tab</button>
<button class="remove">Remove Tab</button>