css Beginner

Outline HTML elements

CSS Outline Demo

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Select all selector and the outline

* {
  outline: 1px solid red;
}

Summary

Add the above code to your main CSS file to take effect.
Select all selector targets all HTML elements and adds outline to them.

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Adrian Bigaj

Creator of BigDevSoon

Full-stack developer and educator passionate about helping developers build real-world skills through hands-on projects. Creator of BigDevSoon, a vibe coding platform with 21 projects, 100 coding challenges, 40+ practice problems, and Merlin AI.

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