Reference: setAxisStyle
setAxisStyle(a, s) sets the style of the axes listed in a, a comma-separated string of axes in {"x", "y"}, to s, a CSS style string, in the current 2D visualization window. Example: setAxisStyle("x, y", "colour:red; number-distance: 2; text-colour:yellow; tick-distance: 2; tick-colour:red") Possible style parameters: colour, number-distance, numbers-visible, text-colour, ticks-visible, tick-distance, tick-colour.