Add Classes with D3 - why cant my code display on code pen?

I’m trying to do the d3 challenges in code pen but my code is not displaying. Is there any setup I’m not getting correctly? Kindly assist guys

Your code so far


Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:67.0) Gecko/20100101 Firefox/67.0.

Link to the challenge:

You need to add units to your height and width.

  background-color: blue;
1 Like

oh silly me! Thank you most