```
{% endtab %}
{% tab title="👥 相關" %}
* 用 **`em`** 會導致累積效應，用 [rem](/web/css/values/unit/relative/rem.md) 可避免這種效應。
{% endtab %}
{% tab title="📘 手冊" %}
* MDN ⟩ [CSS values and units](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Values_and_units)
{% endtab %}
{% tab title="📗 參考" %}
* [一次搞懂 CSS 字體單位：px、em、rem 和 %](https://www.oxxostudio.tw/articles/201809/css-font-size.html)
{% endtab %}
{% tab title="💈範例" %}
{% embed url="" %}
{% endtab %}
{% endtabs %}
---
# Agent Instructions: Querying This Documentation
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```
GET https://lochiwei.gitbook.io/web/css/values/unit/relative/em.md?ask=
```
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