Friendly Tag Url

Howdy,

In settings of SEO addon, I set "Other SEO URL format" to /item.html

My tag url(s) in product detail page:

http://abc.com/tag.html?tag=gopro+4

I need to rewrite the url for more friendly:

http://abc.com/tag/gopro-4

I tried to google how to do this, and write something like:

RewriteRule ^tag/([0-9A-Za-z\+]*)/?$ tag.html?tag=$1 [R=301,L]

and:

RewriteRule ^tag.html\?tag=$ http://abc.com/tag/$1/[R=301,L]

but no luck for me.

When I write:

RewriteRule ^tag.html$ http://abc.com/tag/$1/[R=301,L]

It rewrites my url from:

http://abc.com/tag.html?tag=gopro+4

to:

http://abc.com/tag/?tag=gopro+4

I feel like I'm close to get results. But I can't do it.

Your help is appreciated.

Anybody here? :(