Grouped linear chart does not work

Hi all,

I am new in JS and I have a few problems with visulizing data using d3.js V7.

The first problem is I created two bar charts by column names race_ethnicity and year, and it works, but both bar charts have white strokes between bars even if I made sure that only numeric values would be taken. e.g. +d.value;. It looks like NaN or dot ( . ) is inside bars.

The second problem is with grouped linear chart. I used the script from this url https://d3-graph-gallery.com/graph/line_several_group.html , and it is not working .
Please have a look at it here https://dads-adv-d3js.grotebroer.repl.co/

I want to understand the reason of the issues in bar and linear charts, and how can I fix them?

Thanks in advance.

Best regards,
Kanatbek