You can change the colors to anything you like. Open the file lib/theme/theme.txt inside your Arduino IDE installation folder. The console background color can be changed by editing the line:
console.color = #000000
The console text color:
console.output.color = #eeeeee
The console error text color:
console.error.color = #E34C00
You can get the hex codes for any color from HTML Color Picker or many other websites and applications.
After editing save the file and restart the Arduino IDE.