Nav divider is wrong color in dark theme

[alisonjoseph]

Should be gray 20 I believe (you can see Carbon v10 website for correct color)

Also in light theme, we should use white background for the left nav for contrast with the gray-10 content background.

Tasks

Beta Give feedback

1. Update nav divider color in dark theme
2. Re-add missing nav border
3. Adjust margin (saw some extra margins — probably to accommodate the banner on the demo)
4. Fix theme light mode nav theme colors

[elycheea]

@alisonjoseph We caught a few more style fixes when we implemented on our end¹. I can update this issue to include those as well and close carbon-design-system/carbon-for-products-website#101 in favor of this issue for tracking.

Footnotes

1. Overrides from PR carbon-design-system/carbon-for-products-webiste#98 ↩