Apply a CSS filter only on background

Question

In the following snippet, I have applied a blur filter on .sub-menu but I the text is also filtered.

How can I apply the blur filter only on the

Answer 1

I suggest more to add separate div wich is blured and put your sub-menu over it:

          
 
            
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                    bla bla 
 bla bla bla
                
              

                
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