按照 VitePress 的格式小改了一下外部链接的样式，不知道要不要交个 PR？

[zhuozhiyongde]

Clear and concise description of the problem

如题，前后对比：

（左为修改后，右为修改前）

主要是换了图标 + 让前面的 logo 变小了一点，并且通过 inline-flex 使这三个元素垂直居中对齐了。

Suggested solution

修改代码可见于：https://github.com/zhuozhiyongde/Shiro/commit/d5d938615f16042aa1be8886e36020e7d9567fe4

Alternative

No response

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guide.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[Innei]

好耶