Left navigation pane: long English titles without spaces misalign

[qiancai]

Describe the bug When viewing long English titles without spaces in the left navigation of the documentation site, the left edge of these titles does not align properly, which is very confusing.

To Reproduce

1. Go to https://docs.pingcap.com/tidb/stable/information-schema-referential-constraints.
2. Check the left navigation pane.

Expected behavior The left edge of titles aligns according to the TOC, regardless of title length.

Screenshots

Desktop (please complete the following information):

• OS: macOS
• Browser: Chrome

[Oreoxmt]

I'd like to share an observation regarding the navigation pane behavior in a previous version of website-docs (https://github.com/pingcap/website-docs/commit/9044798d9c52945427cfecebbae1498eefd609d8). When previewing a document on my local machine, I noticed that the previous version handled these cases correctly:

• Title alignment: all titles were properly aligned to the left edge
• Text overflow: long text entries had proper horizontal scrolling functionality