CSS behavior changes between chrome and firefox

I'm having trouble configuring a button so that the image on the right is displayed on the right. This button should properly erase whether the icon is present or not. This is the CSS I am using:

.myButton {
-webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
-moz-box-sizing: border-box;    /* Firefox, other Gecko */
box-sizing: border-box;         /* Opera/IE 8+ */
background-color: #ABCDE5;
border-color: #A5C6DD;
border-width: 1px;
height: 30px;
padding: 5px 10px 5px 10px;
float: right;
margin-right: 30px;
font-family: AdelleSans-SemiBold;
text-decoration: none;
font-size: 16px;
color: #FFFFFF;

}
.myButton:hover {
    -webkit-box-shadow: 1px 1px 4px 0 rgba(0,0,0,0.25);
    -moz-box-shadow: 1px 1px 4px 0 rgba(0,0,0,0.25);
    box-shadow: 1px 1px 4px 0 rgba(0,0,0,0.25);
}
.myButton.disabled {
    pointer-events: none;
    cursor: default;
    background-color: #ABCDE5;
    border-color: #A5C6DD;
    opacity: .4;
}

.myButton.icon span{
    width: 20px;
    margin-right: 15px;
    padding-right:70%;

    vertical-align: middle;
    background: url(export.png) no-repeat 60px 2px;

}

      

        
        
        
      

    

which is called by the html tag as such:

<a class="myButton icon" href="#" ><span>Export</span></a>

      

        
        
        
      

    

I probably missed something really small, or my implementation might be removed, but I can't believe this is going wrong. Firefox does it perfectly, while the button doesn't grow wider in Chrome

Appreciate any help, thanks