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CSS Errors


CSS Errors

Errors in CSS can lead to unexpected behavior or styles not being applied correctly. This page shows common CSS mistakes and how to avoid them.


Missing Semicolons

Forgetting a semicolon at the end of a property declaration can break the style rule.

Example

.bad {
  color: red
  background-color: yellow;
}
Try it Yourself »

Invalid Property Names

Using a property name that does not exist will simply be ignored by the browser.

Example

.bad {
  colr: blue;
  font-size: 16px;
}
Try it Yourself »


Invalid Values

Correct properties but invalid values will also be ignored.

Example

.bad {
  width: -100px;
  color: green;
}
Try it Yourself »

Unclosed Braces

If you forget to close a brace }, the entire rule may be ignored.

Example

.bad {
  padding: 20px;
  margin: 10px;
Try it Yourself »

Extra Colons or Braces

Typos like extra colons or misplaced braces can cause rules to break.

Example

.bad {
  color:: blue;
}
Try it Yourself »

Tips to Avoid CSS Errors

  • Use a code editor with syntax highlighting.
  • Validate your CSS with a CSS linter or validator.
  • Write CSS in small sections and test frequently.


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