It looks like this CSS style was affecting how buttons appeared in your document:
*,input[type="search"] {
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
}
We should probably insulate buttons better from this external style.
To override this, you can set this CSS style anywhere in the head of your document:
.HYPE_element {
-webkit-box-sizing: content-box;
-moz-box-sizing: content-box;
box-sizing: content-box;
}