I basically have a problem where my button should sit on the same height as my input boxes, and all the information I have read online seems to say what I am doing is correct, but despite there being no padding on the button it still sits around 3px lower than it should do. 

It can be seen here: <http://jsfiddle.net/spadez/8Ej9U/embedded/result/>

This is its properties:

```css
#search_form .button {
    width:70px;
    line-height:0;
    font-size:0;
    text-indent:-999px;
    color: transparent;
    background: url(http://i.imgur.com/LCQSXXY.png) no-repeat #a6668e center;
    border: 1px solid #3079ED;
}

```

My question is, if the button and the input field are both 31px with no padding, why do they sit at different heights and how should I be fixing this?