Reply To: Disfigured PayPal Buttons

Check out line 378 in your css for the input/forms and remove or comment out the width: 100%; –

/* Forms
--------------------------------------------- */

input,
select,
textarea {
	background: #fff;
	border: 1px solid #ddd;
	border-radius: 3px;
	color: #999;
	font-size: 16px;
	padding: 6px 12px;
	width: 100%;
}