Based on https://wago.io/BHKBnayrV I've modified this aura for my fire mage, also replacing numbers with example of spells so I can think less and push button(s) more.
Greater than 36 yards (black background, out of range)
31-36 yards (green background, in range for fireball)
21-30 yards (green background, in range for frostbolt, polymorph, flamestrike, blizzard)
10-20 yards (yellow background, in range for fire blast)
Less than 10 yards (red background, in range for frost nova, arcane explosion)
Uses Arcane Missiles, Fireball, and Fire Blast to determine range. Will not work if those spells are not learned.
In action:
https://altamis.net/mage-ranga-waura.mp4