Because the default width of the submit button was not same in both IE and FF. And the text align property for button or submit can't apply in FF, only in IE. So you see the white space. You can set the exceed width for the button to see both IE and FF with the same result. I don't know how much text do you wanna put in the button and it depends on you.
Here is example.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<style type="text/css">
#mapInfoTabBorder div.TabBorderInactiveTab {
color: #ffffff;
padding: 0;
margin: 0;
background: yellow;
border: none;
}
#mapInfoTabBorder div.TabBorderInactiveTab input {
background: green;
color: #FFF;
width: 67px;
border: 1px solid #eee;
-moz-border-radius: 7px /* IE can't understand */
}
</style>
</head>
<body>
<div id="mapInfoTabBorder">
<div class="TabBorderTabs">
<div class="TabBorderInactiveTab">
<input name="TabSubmit" value="Submit" type="submit"
/>
</div>
<div class="TabBorderActiveTab">
Info
</div>
<div class="TabBorderInactiveTab">
<input name="TabSubmit_0" value="Reset" type="submit"
/>
</div>
<div class="TabBorderInactiveTab">
<input name="TabSubmit_1" value="Cancel" type="submit"
/>
</div>
</div>
</div>
</body>
</html>Good luck.. and forgive my English skill.