Map size in %

Hi!
I like your plugin.
I would like to know how I can use it in % instead of px for a responsive website. It seems to be possible: http://themeforest.net/item/smartstart-wp-responsive-html5-theme/full_screen_preview/2067920

They are using your plugin and it is in %

Thx

http://wordpress.org/extend/plugins/wp-gmappity-easy-google-maps/