If you are not using a logo on your Wordpress theme and just have text for the site title or sitename, here is where you can change the site name color in the OceanWP theme. In the OceanWp Customizer (Wordpress's Appearance/Customize) go to Header/Logo section and scroll down to the Color setting and use the color picker or type in your hex value. This will change the text color in the header.
Oceanwp Page Title At Top Of Page Settingsfor Background Image etc. Fonts Page Title at top of page, font settingsCustomizer/Typography/Page Title Using the Customizer/Typography/H1 does not affect font family on page title. Page Title Background Image and Background banner HEIGHT General Options/Page TitleStyle:Background ImageImage: position, repeat, size, height, overlay opacity and colour, (this only seems to work for new pages from a fresh install, doesn't work for imported sites from old Oceanwp sites) To adjust height of the title background; go to Padding and change the padding top and bottom. Can be adjustable for desktop and mobile. Show or hide on Devices Hide Breadcrumbs or Title Customizer/General Options/Page Titlescroll down to Breadcrumbs