Change Font Colour of Blog Comments

Hello, Do you have a CSS code to change the colour of the 'Leave a Reply' heading in the comment box at the bottom of a blog post It's currently black which doesn't work with the black background, so I'm hoping to change to white so it is easier to see. See at the bottom of the following blog post: https://wafflesandlamingtons.com/my-authentic-walking-tour-of-bruges/ Thanks, Theo.