W3C validator issue

Hi, I get such error after validating pages with the ASL from W3C as

Bad value http://www.w3.org/1999/html for the attribute xmlns (only http://www.w3.org/1999/xhtml permitted here).
from <style type=”text/css” xmlns=”http://www.w3.org/1999/html”&gt;
and warning
Attribute xmlns is not serializable as XML 1.0.
From </style><style type=”text/css” xmlns=”http://www.w3.org/1999/html”&gt;

Please fix it.

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