Visualize Data with a Bar Chart help with setting width and styling on bars

Tell us what’s happening:
Hi can someone help out with setting the width on my bars, you can see on my codepen that it is over running my x-axis. I am a little confused on how to calculate the bars correctly. All my test are fine currently, but I am having trouble with the equation for styling.

Also how do you get the borders, maybe margins on the bar lines, so you can see some separation?

Your code so far

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