Capiral Gains basic questions

[Jay Yoo]

Hello

Would the capital gains tax happen on the amount after the mortgage is paid off and subtracted the initial invested fund?

For example, if a property was purchased for $100k and mortgage $70k and invested $10k plus 10k for closing fee, and sold for $110k after one year (I know there is the minimum term and filing jointly variations)

Would Capital gain tax create against $20k for profit left over? Or capital gain towards to the whole $110 amount?

Thank you for your time!