At the very top of your code (before the <style> tag and everything), you have to put some text in order for the CSS to work on rpn. A lot of people have been using <p style="display: none;">random message here</p> to get it done. You can also just use empty <p> tags.
Edit:
@IctoraPost
Call me stupid, but it never occurred to me that I could download a separate html tester.
That and I don't use javascript/jquery, since I only learned html for rpn, so I thought an online tester would suffice. Do you have any downloadable ones that you suggest?
Sometimes, when I post a code on rpn, it screws with the margins I set? I always use px instead of percent, so it isn't the width being screwy. The issue is most noticeable when you view the code on different themes, although it's not always an issue. I don't have this problem when going from html tester to html tester, so I think it just has to do with the fact that I'm pasting code into a post rather than a whole site page?
<style>
.scrolly::-webkit-scrollbar {
}
</style>
<div class="scrolly">
content
</div>
<style type="text/css">
.stonecode1{
margin:auto;
background-color:#e6ccff;
height:500px;
width:1000px;
overflow:hidden;
padding:10px;}
.stoneborder{
border:white double 2px;
height:480px;}</style>
<div class="stonecode1">
<div class="stoneborder">
<div style="color: white; font-family: "Brush Script MT", cursive; font-size: 48px; text-align: center;">
Character Name Here
</div>
</div>
</div>