So what you need:
-mirror film (maybe the most difficult stuff to find just go in a huge DIY store) Take care for this one it is sold in big roll !
-a power supply
-a plexiglass sheet at the same size of the mirror or slightly bigger!! :)
-2 small magnet balls
Step 1: Open the Solar Light!
Step 2: Leds Soldering and Box Insertion!
After you just need cardboard to fix your led in a rigid structure!
For a better and stronger render just create a wood frame to the tailored size!
Put the mirror behind leds!
Step 3: The Full Circuit!
Step 4: The Final Result!
Step 5: The Bonus
I create a magnet power supply totally useless but just for fun !
See the comments on pictures :)
Step 6: You Say Finition?!
The aim here is now that you know to create a magic mirror!
Have a nice try and share your DIY!