how to change the colour of the text/menu widgets?

A:
1. Open style.css in your host, it is normally at wp-content/themes/restaurant/
2. replace all #660000 into the color you like

Won’t that be overwritten when the theme is updated?

didn’t think of that.
what would you recommend?

also, i was planning to add a color pick-up option in dashboard next version to do this kind of work.

We generally recommend that Child Themes be used for ANY modifications to theme files. (Assuming your theme will work with a child theme – some won’t – which is really not ideal for users.)

If the user just wants to make CSS changes, there are quite a few plugins that will add Custom CSS – and the new CSS can be added there.

Some themes have a custom CSS option built in, so you might consider adding that :).

Thanks for your help.

I will provide a custom CSS and a css plugin next time.