You should put the button inside a div, and in the div you should be able to use the classes:
text-left, text-center and text-right.
for example:
<div class="row">
<div class="col text-center">
<button class="button button-small button-light">Search</button>
</div>
</div>
And about the "textarea" position:
<div class="list">
<label class="item item-input">
<span class="input-label">Date</span>
<input type="text" placeholder="Text Area">
</label>
Demo using your code:
http://codepen.io/douglask/pen/zxXvYY