Why didn't the direction go from bottom to top

[Sunny264]

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• Not a duplicate.
• Not a question, feature request, or anything other than a bug report directly related to Splide. Use Discussions for these topics: https://github.com/Splidejs/splide/discussions

Version

4.1.4

Description

Why didn't the direction go from bottom to top。There are only three directions, I hope to add another direction

Reproduction Link

No response

Steps to Reproduce

1111

Expected Behaviour

1111