This is not going to work. Your sketch is configured to use hardware SPI, but pin 12 on the Pro Mini is the MISO hardware pin. You can't also use it as CS. This makes me think that not only is your code messed up but your wiring is likely also messed up.
You need to make the following connections:
display | Pro Mini
MOSI | 11
MISO | 12
CLK | 13
You can then connect the display's DC and CS pins to whichever unused pins on your Pro Mini you like. Since there are restrictions on what you can do with pin 10 when using hardware SPI, it is common to use that for CS, but not required. Make sure to update the sketch according to the new DC and CS pins you are using.
You don't use the TFT_MOSI, TFT_CLK, and TFT_LED macros anywhere in your sketch, so you might as well delete those lines of code, since they might cause confusion.