Why is this youtube subscribe button moving itself about 10 pixels in Firefox and IE, compared to Chrome? I need it to show in the same spot on all 3 browsers! Please help.

Code:
<div id="youtube2"><div id="youtube"><a href="//www.youtube.com/subscription_center?add_user_id=OYYq1HZyyMf6GyPoPmwwCw&feature=creators_cornier-//s.ytimg.com/yt/img/creators_corner/Subscribe_to_my_videos/YT_Subscribe_61x23_red.png"><img src="//s.ytimg.com/yt/img/creators_corner/Subscribe_to_my_videos/YT_Subscribe_61x23_red.png" alt="Subscribe to me on YouTube"/></a><img src="//www.youtube-nocookie.com/gen_204?feature=creators_cornier-//s.ytimg.com/yt/img/creators_corner/Subscribe_to_my_videos/YT_Subscribe_61x23_red.png" style="display: none"/></div></div>

<style>
#youtube2 {
position: relative;
top: -263px;
left: -180px;
z-index: 1001;
}

#youtube {
position: absolute;
}

</style>