bugfix: Update current subnav nav item position

[bencodezen]

Summary

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

If changing the UI of default theme, please provide the before/after screenshot:

Before: https://cl.ly/0r1X220Y071I
After: https://cl.ly/3c29140o3S15

Note: The position of the left arrow cannot be perfectly vertically middle aligned with absolute positioning. I played with different values and this seemed to be the best compromise.

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)

You have tested in the following browsers: (Providing a detailed version will be better.)

• Chrome
• Firefox
• Safari
• Edge
• IE

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature
• Related documents have been updated
• Related tests have been updated

To avoid wasting your time, it's best to open a feature request issue first and wait for approval before working on it.

Other information:

[ulivz]

Thanks, but it's duplicate of #508

[bencodezen]

Completely missed that! Sorry about that @ulivz. Let me see if I can include a mobile fix as well.

[ulivz]

@bencodezen Thanks, the fix included mobile was also in 5fcac1b