### What is expected
鼠标放在左右分割线上时,箭头应该是左右方向
### What is actually happening
鼠标放在左右分割线上时,箭头是上下方向
![20230717145735_rec_](https://github.com/opentiny/tiny-vue/assets/31911231/167b5887-90b2-44da-86fd-d6b32a699bd6)
### Any additional comments (optional)
_No response_
Version
官网帮助文档演示
Vue Version
官网帮助文档演示
Link to minimal reproduction
https://opentiny.design/tiny-vue/zh-CN/os-theme/components/split#nested-use
Step to reproduce
左右分割嵌套上下分割
改为上下分割嵌套左右分割
,比如改为: