Add gray background to the X-axis ruler.
Add gray background to the X-axis ruler.

Signed-off-by: Sean Loughman <d7e19930cc1f42c2d0781f4d9e6f1fe5891bf9cf@studiospring.com.au>

uxbox/uxbox,uxbox/uxbox,studiospring/uxbox,studiospring/uxbox,studiospring/uxbox,uxbox/uxbox