Vertical navigation arrows missing

[strarsis]

Check that this is really a bug

• I confirm

Reproduction link

https://codesandbox.io/p/devbox/swiper-vertical-forked-z75cpx?selection=%5B%7B%22endColumn%22%3A20%2C%22endLineNumber%22%3A77%2C%22startColumn%22%3A20%2C%22startLineNumber%22%3A77%7D%5D

Bug description

When using vertical mode, the navigation arrows are incorrectly displayed in horizontal direction.

Previous issue (was closed as stale): #3592

Expected Behavior

With a vertical slider, navigation arrows being displayed in vertical direction.

Actual Behavior

With a vertical slider, navigation arrows being displayed in horizontal direction.

https://codesandbox.io/p/devbox/swiper-vertical-forked-jq5yyo?selection=%5B%7B%22endColumn%22%3A1%2C%22endLineNumber%22%3A63%2C%22startColumn%22%3A1%2C%22startLineNumber%22%3A63%7D%5D

PR with style additions: #7429

Swiper version

11.2.1

Platform/Target and Browser Versions

Windows 10 with latest Chrome

Validations

• Follow our Code of Conduct
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.
• Make sure this is a Swiper issue and not a framework-specific issue

Would you like to open a PR for this bug?

• I'm willing to open a PR