Regex to remove HTML attribute from any HTML tag (style="")?

Perhaps a simpler expression is

 style="[^\"]*"

so everything between the double quotes except a double quote.

I think this might do it:

/style="[a-zA-Z0-9:;\.\s\(\)\-\,]*"/gi

You could also put these in capturing groups, if you wanted to replace some parts only

/(style=")([a-zA-Z0-9:;\.\s\(\)\-\,]*)(")/gi

Working Example: http://regexr.com?2up30