Blogger automatically adds a couple of not-so-useful stylesheets to your blog’s front-end preview. Styles in these sheets styles all the official Blogger widgets, so only remove this if you know what are you going to do. So…
In this tutorial, I’ll show you how to remove default CSS from Blogger without breaking your Blogger template. It will also improve your blog’s load time. We will turn just converting that code to HTML comments.
Navigate to your Dashboard > Template > Edit HTML, proceed, then CTRL+F this code:
<b:skin><![CDATA[
If you found this line, copy all the CSS code from the below and store this CSS to a notepad or anywhere because we need this code later.
Then the remaining code is:
<b:skin><![CDATA[ ]]></b:skin>
Replace above code with following:
<style type="text/css"> <!-- /* <b:skin><![CDATA[ */]]></b:skin>
That’s it! We just removed default Blogger CSS, but wait! Closing window on this point will completely destroy your template. Now, we need to place your CSS back to your template.
Post following code just above the </head> of your template:
<style type='text/css'> CSS CODE WHAT WE COPIED EARILER </style>
Now you can save your template!