What do you mean by inline CSS. You can't "create" a page using CSS. CSS doesn't create, it styles. Inline CSS looks like this:
<p style="color:green; font-size:110%">This is a paragraph that is green and larger than the rest.</p>
Are you talking about adding such CSS to your post or Page and it isn't found? Odd. HTML/XHTML tags and CSS works fine in WordPress posts. If you are including a lot of inline CSS and HTML in your posts, I recommend that you get TextControl Plugin to really control the way WordPress converts your post when generated on a post by post basis.
Are you talking about using a template file called
post.php that has a different header or a header with the
head that brings in a different style sheet from the rest of your posts? That's a style link.
And are you talking about a Page or a static php file, or a single post template (what you see when you click on an individual post view)?
We just need a little clarity on this.