如何使带背景图片的Button按钮中的文字居中偏上显示

.button_submit {
/* background: #df5e16;  */
background:url("../images/image_mobile/m_start.png") no-repeat;
height: 33px;
line-height: 33px;
font-size: 18px;
color: #000;
font-family: 'Microsoft YaHei' !important;
font-weight: normal !important;
border: none;
width:229px;
text-align: center;
/* 	vertical-align:middle; */
/* 	margin: 0 auto; */
display:inline-block;

}

.button_submit:hover {
background:url("../images/image_mobile/m_select.png") no-repeat;
height: 33px;
line-height: 33px;

font-size: 18px;
color: #000;
font-family: 'Microsoft YaHei' !important;
width:229px;
/* vertical-align:middle; */
margin: 0 auto;
display: block;
}

<div style=" padding-top: 40px; text-align: center;" >
<button  class="button_submit" type="submit">
<div style="padding-bottom: 5px; font-size: 16px;" class="yahei">提  交</div>
</button>
</div>