Changing colour of the numbers along the x and y axis

[S McCarthy]

Hi, At the minute I'm using google charts for a final year project and i can't seem to figure out how to change the colour of the numbers on the x and y axis. I'm using a grey background so ideally i need to change these number to a white font. I have managed to do so for the titles but not the numbers, anyone have any ideas? Thanks in advance.