IndexBar 索引栏与Tab 标签页显示问题 about vant

[github-actions]

Hello @hoscent. Please provide an online reproduction demo by codesandbox or a minimal GitHub repository. Issues marked with need reproduce will be closed if there is no activity within 3 days. For background, please refer to Why reproductions are required.

你好 @hoscent, 我们需要你提供一个在线的重现示例，以便于我们帮你排查问题。你可以通过点击 codesandbox 创建，或者提供一个最小化的 GitHub 仓库。如果 3 天内未跟进，此 issue 将会被自动关闭。背景请参考 为什么需要最小重现。

[github-actions]

As the issue was labeled with need reproduce, but no response in 3 days. This issue will be closed. Feel free to comment and reopen it if you have any further questions. For background, please refer to Why reproductions are required.

由于该 issue 被标记为 "需要重现"，但在 3 天内没有回应，因此该 issue 将被关闭。如果你有任何进一步的问题，请随时发表评论并重新打开该 issue。背景请参考 为什么需要最小重现。