Xperia C2 Red Light Of Death
So as i have done research on all the steps you have provided it seems like there are many ways that this device Xperia C2305 can be bricked in many ways . We call this the *Xperia C2 Red Light Of Death*
As i recommend you to use the original stock rom after flashing a themed rom you could have bricked your phone i will not help on that but if you havent done anything and your phone simply doesnt start that could mean it needs a JUMPSTART like if you have lost power to the device the charging wouldnt help you , the green light appears when u press pretty much all the buttons.
Step 1 : Remove the back Panel off the device
Step 2 : Hold a pin or something to press the hard reboot button
Step 3 : Connect the power cable + press the power on button + press the hard reboot
Your device should start if YOU HAVENT BRICKED IT BY FLASHING WRONG THINGS