Question

I noticed my input button does not look correct in Firefox and I can’t figure out how to make the value (text) appear in the proper location.

.rb {
    width: 142px;
    height:142px;
    float:left;
    background:#2F2F2F;
    color:#FFF;
    font-size:95%;
    line-height:210px;
    margin-top:15px;
    border:0;
    outline:none;
    padding:0;
    text-align:center
}

.rbSubmit {
    background: url('http://www.41q.org/admin/img/sprite_icon.png') -568px -200px no-repeat;
    color:#808080
}

<input id="rbSubmit" class="rb rbSubmit" type="submit" value="submit">

Answer 1

http://jsfiddle.net/qzYVP/1/

This relies on explicit sizing using height + padding + line-height equal to font-size. Works in IE8/9, FF, Chrome.

.rb {
    width: 142px;

    /* tweak these to get the exact font size/position desired */
    height: 14px;
    font-size: 14px;
    line-height: 14px;
    padding: 90px 0 38px 0;

    float:left;
    background:#2F2F2F;
    color:#FFF;
    margin-top:15px;
    border:0;
    outline:none;
}

Example with relative font size: http://jsfiddle.net/qzYVP/2/