value range

Hey,

i was hopeing that someone might could help me.
I would like a script which makes value different colors like;

-0.2 > 0.2 = text will be black
0.21 > 0.7 = text will be orange
0.7 > 100 = text will be red

I have tried this:

if (event.target.textColor =event.value>=-0.2 && event.value<=0.2) 

    event.target.fillColor = color.orange; 

else if (event.target.textColor =event.value>=-0.2 && event.value<=0.2) 

But it dosen't work the way i would

Thanks in advance!