Some headings are invisible

[Shuyib]

If you have looked at the notebook Data_visualisation_tool_YT.ipynb you'll notice spaces without text. Please make use of nbviewer to view the notebook. How? Click on the "-" icon to the right of the notebook file. You'll see some text pop-up after hovering your mouse towards the icon "Limited rendering only, external view available with nbviewer" click on the text marked in blue that is, external view available with nbviewer. And you'll be able to see everything.

[Shuyib]

I decided to change this entirely by removing the colors i put on the titles to the standard form which is black.