CodePen

HTML

            
              <div class="column">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>
<div class="column">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>
            
          
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↑ Insert the most common viewport meta tag

CSS

            
              body {
  text-align: center;
}

.column {
  display: inline-block;
  text-align: left;
  vertical-align: top;
  width: 300px;
}

.column > div {
  outline: 1px solid red;
  padding: 10px;
}

.column > div:hover {
  height: 10em;
}
            
          
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JS

            
              // http://css-tricks.com/forums/discussion/24458/annoying-layout-issue-#Item_3
            
          
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