Using spaces before and after the `=` sign of HTML element attribute

I am wondering if there's a "best" approach to having a space before and after the equal sign in a HTML page when you write it down. It seems like no one is using this, but for me it seems fairly natural coming from programming languages that have this printed in their basic code style. So, is there any standard that you have to not use space before and after the equal sign of an attribute of an HTML element ?