Hi @techeez,
It looks like you’re using the TablePress plugin to insert the tables. The styling that you see (colored header) is actually added by TablePress, not Graphene.
By extension, I believe the feature that makes the table displayed as rows when viewed on mobile devices also comes from TablePress. If I’m not mistaken there should be a feature to disable that feature in TablePress. You might have to dig around in the plugin’s settings to find it, or ask at the plugin’s support forum.