Rrddzzz

Do it in a custom slider styleheet. Relevant section is
.slideshow_container .slideshow_description { background: #000; width: 100%; }
.slideshow_container .slideshow_description h2 { font-size: 1.3em; text-align: center; }
.slideshow_container .slideshow_description p { text-align: center; }
.slideshow_container .slideshow_description h2 a,
.slideshow_container .slideshow_description p a { color: #fff; }

Thanks everyone. Edit Css is the custom css module of the jetpack plugin in. Will deactivate it and stick with the child style.css

Installed plugins are
Askimet, jetpack by wordpress.com, w3 total cache, wordpress seo.

Sorry for not being clear enough, will try again.

When editing the child stlye.css using
Dashboard – Appearance – Editor
the location of the edited child style.css is:
/themes/child-theme/style.css

When editing the style sheet by going to
Dashboard – Appearance – Edit CSS
changes take effect but there are no changes made to the child style.css located at:
/themes/child-theme/style.css
What is the location of the style sheet that is changed by
Dashboard – Appearance – Edit CSS ?