CSS 中使用 px，em，rem

目前还不理解它们的应用场景，暂时倾向于使用 em,rem 少用 px 。

一种观点：

• Pixels are ignorant, don't use them.
• Use REMs for sizes and spacing.
• Use EMs for media queries.

——来自阅读材料 1

一些阅读材料：

1. https://engageinteractive.co.uk/blog/em-vs-rem-vs-px
2. https://stackoverflow.com/q/11799236/12539782
3. https://zellwk.com/blog/media-query-units/
4. Numbers, lengths, and percentages - MDN
5. REM vs EM – The Great Debate
6. https://web.dev/learn/css/sizing/
7. What does 100% mean in CSS?
8. https://www.w3.org/TR/css-values-4/#px