Child Theme Changes Default CSS Behavior, Maybe?

Using child themes on Sporty seems to change the default CSS behavior, even if you just include the original style.css into your child style.css, making no other changes. For example, doing this appears to change the default color of Site Title and Site Description, even if you haven’t changed the text color. Changing the text color is supposed to change the Site Title and Site Description, according to the custom-header.php code. At least that’s how it reads to me.

I have a development site where I playing around with Sporty. You can see here I have changed the background color of site-header and site-introduction. But I cannot change the color of site-title or site-description because they are set to black by styles in the page html head section and the are emphasized with !important. I haven’t changed the default text color.

The only changes I usually made to themes are in style.css. I would like to change the colors of Site Title and Site Description, plus other things. Not really interested in a CSS plug-in. Thanks.