Colour in AB Container

hi – using the AB Container block on a page with headings, text and images. Despite having no colour options set on headings and text blocks the AB Container seems to be setting its own colour for headings and text, overriding my themes settings. I can change this with my own css but wondered why it is doing that? Can you help – shouldn’t the default be for there to be no colour set by AB Container and therefore it defaults to the theme colours?

I can see it being set here:

.ab-block-container {
    margin: 0 0 1.2em 0;
    position: relative;
    background: #fff;
    color: #293038;
    padding: 0;
}