Center submit button

We need to center the submit button on the following page: https://www.ibogo.club/merchant-signup

Below is the CSS for the submit button of the form:

/*                                                    */
/*   FORM submit button                               */
/*                                                    */

p.cf-sb {
	text-align:right;
	padding: 0!important;
	margin: 0;
}
.cform input.backbutton,
.cform input.resetbutton,
.cform input.sendbutton	{
	padding:5px 10px;
	margin: 0 0 0 5px;
	font-size:0.8em;
	cursor:pointer;
	width:auto;

    border-radius: 3px 0 0 0;
	-moz-border-radius:3px 0 0 0;
	-khtml-border-radius:3px 0 0 0;
	-webkit-border-radius:3px 0 0 0;

	border:1px solid #ccc;

	background: #f7f7f7; /* Old browsers */
	background: -moz-linear-gradient(top,  #f7f7f7 1%, #e5e5e5 100%); /* FF3.6+ */
	background: -webkit-gradient(linear, left top, left bottom, color-stop(1%,#f7f7f7), color-stop(100%,#e5e5e5)); /* Chrome,Safari4+ */
	background: -webkit-linear-gradient(top,  #f7f7f7 1%,#e5e5e5 100%); /* Chrome10+,Safari5.1+ */
	background: -o-linear-gradient(top,  #f7f7f7 1%,#e5e5e5 100%); /* Opera 11.10+ */
	background: -ms-linear-gradient(top,  #f7f7f7 1%,#e5e5e5 100%); /* IE10+ */
	background: linear-gradient(top,  #f7f7f7 1%,#e5e5e5 100%); /* W3C */
	filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#f7f7f7', endColorstr='#e5e5e5',GradientType=0 ); /* IE6-9 */
}
.cform input.backbutton:hover,
.cform input.resetbutton:hover,
.cform input.sendbutton:hover {
	border:1px solid #aaa;
	background: #fdfdfd; /* Old browsers */
	background: -moz-linear-gradient(top,  #f7f7f7 1%, #c1c1c1 100%); /* FF3.6+ */
	background: -webkit-gradient(linear, left top, left bottom, color-stop(1%,#f7f7f7), color-stop(100%,#c1c1c1)); /* Chrome,Safari4+ */
	background: -webkit-linear-gradient(top,  #f7f7f7 1%,#c1c1c1 100%); /* Chrome10+,Safari5.1+ */
	background: -o-linear-gradient(top,  #f7f7f7 1%,#c1c1c1 100%); /* Opera 11.10+ */
	background: -ms-linear-gradient(top,  #f7f7f7 1%,#c1c1c1 100%); /* IE10+ */
	background: linear-gradient(top,  #f7f7f7 1%,#c1c1c1 100%); /* W3C */
	filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#f7f7f7', endColorstr='#c1c1c1',GradientType=0 ); /* IE6-9 */
}
.cform input.resetbutton {
	width: auto;
	padding:5px 1em;
}
.cform input.backbutton {
	width: auto;
	padding:5px 1em;
}

If anyone can help by suggesting a way to center the submit button it will be greatly appreciated.