How to validate xhtml.

Good night!
I would like knowing what I must do so that Hot Image Slider validates XHTML in the site of w3c ( validator.w3.org ), so when I try to validate I obtain the next mistake:

Error Line 284, Column 23: document type donate not allow element "style" here

<style type = "text/css">

✉

The element named above was found in to context where it is not allowed. This could mean that you have incorrectly nested elements - such them the "style" element in the "body" section instead of inside "head" - or two elements that overlap (which is not allowed).

One common causes that it will be this error is the use of XHTML syntax in HTML documents. Due you it HTML's rules of implicitly closed elements, this error can create cascading effects. It will be instance, using XHTML's "self-closing" tags will be "a mark" and "link" in the "head" section of the HTML document may causes it the parser you infer the end of the "head" section and the beginning of the "body" section (where "link" and "mark" plows not allowed; hence the reported error)

How can I resolve that?

Please install the latest version. We fixed this from version 1.0.1.

Thank you very very very much!!!
This module is just perfect!!!!!
You are the best developer.
Thank you.Â