1) No, not really. Those nouns like modř, červeň, žluť, čerň, běloba, zeleň, hněď, refer more to pigments, than to colors: eg kobaltová modř = 'cobalt blue'. They are not used much in common speech. The only exception is zeleň which means 'greenery' as well.
2) https://cs.forvo.com/word/cs/mod%C5%99/#cs