#eswsInquiryButton a {
 background-image: url("http://www.easy-house.jp/btnInquiry_tel_before.jpg");
}

#eswsInquiryButton a:hover {
 background-image: url("http://www.easy-house.jp/btnInquiry_tel_after.jpg");
}

#eswsInquiryButton a {
 background-position: left top;
 background-repeat: no-repeat;
 display: block;
 height: 40px;
 text-indent: -9999px;
 width: 396px;
}

#eswsInquiryButton {
    position: absolute;
    width: 400px;
}