tune visual effects for better look

[cnwzhjs]

tuned CSS for better look:

[ghostiam]

Hi. Sorry for the delay in response and thanks for PR!

[ghostiam]

I looked at your design, but I would like to leave the original design.
My design is less good, but it is only intended to show the essence of the code.
It is also colored, which gives better understanding when pointing at points and when connecting/disconnecting arrows.

However, thanks for the PR, I will not close it, maybe someone will find something useful in it.

[cnwzhjs]

Sure. It's up to you.