有人知道这些好看的 Diagram 是用什么工具做的吗

作者回我了，内容如下。用 Figma 做的。果然是如 1 楼所说「图片的优雅程度取决于作者的审美」。

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Sure! I generally use Figma to create these figures but I do want to stress that the tool is almost irrelevant for creating these visuals. Creating the visuals in something like PowerPoint or keynote would take the same effort. The primary reason why I use Figma is so that I can easily create svg files for light-weight hosting. I would actually advise using something like https://excalidraw.com/ to create visuals. It's a minimal framework that allows you to focus on the design rather than 100s of unnecessary features.
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