Currently for the Tab Block, there is just a blue outline that tells you what tab you have clicked on. It would be better if the tab where to change color to show which one you are on.

Also, when the page is first loaded, it does not tell you what tab you are on. I know it should be obvious you are on the first one. But it would improve the experience if the first tab was already highlighted. This would also make it more obvious you can click on other tabs.