Genesis Column Classes with clear-line div

<div class="one-third first">This is my first column. It is a lot longer than the one's that follow. I hope this will not cause any issues!</div>
<div class="one-third">This is my second column. It is shorter than the first.</div>
<div class="one-third">This is my third column.</div>
<div class="clear-line"></div>