When one visits http://validator.w3.org/ to validate ones Blogger Blog for errors, it is normal to find that your site has hundreds of errors and warnings. Try as hard as you might want, you are unable to resolve this problem satisfactorily and the errors and warnings in Blogspot remain unresolved.
While searching for answers on how to remove the errors and warnings, I came across a relevant topic on the Google Products Forum regarding the default CSS of Mobile Templates and how to resolve this problem, you can read the discussion here – Here
A simple CSS Code has to be inserted inside the Blogger Template. If unsure or editing the template for the first time download and save your template.
The open your template and add this small CSS code as shown below above/ before –
So that the final code looks like this –
/* style for mobile site */
/* style for desktop site */
Now visit http://validator.w3.org/ to validate your site. The hundreds of errors and warnings come down to 13 or 14 errors and 4 to 5 warnings.
Hope this tutorial helps those publishing on Custom Templates as well as the default Blogger Templates.