Added the colour contrast for the white exclamation mark on red background (on page "Hosts)

@OLLI_S Some of the suggestions are now live and Personal is now 1.0, thus, no longer beta. I've checked the spelling of Prerelease, and Prerelease is an official word, without the -, so we kept it as is. https://vulndetect.org/topic/472/release-secteer-vulndetect-personal-corporate-and-backend-2020-08-20

@Tom Done

This feature is implemented, now there are icons (arrows) that indicate the collapse feature: Thank you @Tom for implementing this feature.