聪明的小主是不是想给Dom元素设置不同的转入和传出动画? 转入用一个，转出用另一个?! 贴心的Svelte满足你： 这次我们把fade和fly 都引入。

Instead of the transition directive, an element can have an in or an out directive, or both together. Import fade alongside fly...

import { fade, fly } from 'svelte/transition';

把transition换成in和out指令

...then replace the transition directive with separate in and out directives:

<p in:fly={{ y: 200, duration: 2000 }} out:fade>
	Flies in, fades out
</p>

现在转场就 不是可反转 的了啊——转入和转出使用了不同的转场动画

In this case, the transitions are not reversed.