css
#container {
display: flex;
justify-content: space-between;
background-color: lightyellow;
}
#container > div {
width: 100px;
height: 100px;
border: 2px dashed red
}
HTML
<div id=”container”>
<div></div>
<div></div>
<div></div>
</div>
http://jsfiddle.net/o5dyoqrx/235/