I have a problem with equal height cols/boxes in bootstrap in combination with nested colored divs. Have a look here how it looks like: https://www.dropbox.com/s/ko6zmqwup4wgasb/bootstrap-equal-height-cols.jpg?dl=0
Actually to set cols to equal heights isn't that problem with flex boxes anymore. The difficulties I encountered is the set it up for the proper look. The bootstrap cols can't have the colored background due to their setup with margins and paddings. Because I have 2 divs within the row wrapper it seems to be difficult to fix this problem. The reduced HTML code:
<div class="row row-eq-height">
  <div class="col-sm-6 col-md-4">
    <div class="portfolio-el bg-dark-gray">
      <div class="view"> 
        <img src="images/image_360x180_1.jpg" alt="dummy">
      </div>
    <div class="portfolio-text-content">
      here goes text which causes different heights of those boxes...
    </div>
  </div>
</div>
<div class="col-sm-6 col-md-4">
  <div class="portfolio-el bg-dark-gray">
    <div class="view"> 
      <img src="images/image_360x180_2.jpg" alt="dummy">
    </div>
    <div class="portfolio-text-content">
      here goes text which causes different heights of those boxes...
    </div>
  </div>
  <div class="col-sm-6 col-md-4">
  <div class="portfolio-el bg-dark-gray">
    <div class="view"> 
      <img src="images/image_360x180_3.jpg" alt="dummy">
    </div>
    <div class="portfolio-text-content">
      here goes text which causes different heights of those boxes...
    </div>
  </div>
</div><!-- end row -->
CSS:
.row-eq-height {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display:         flex;
}
.bg-dark-gray {
    background: #efefef;    
}
all the rest is done by bootstrap classes > grid, etc. I have seen examples giving the cols flex: 1, but I need a height of 100% for the divs with the gray background. Any ideas or workarounds? Cheers