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# Spot the Mistakes: CSS

**By:** [Daniel Cranney](https://www.wearedevelopers.com/@daniel-cranney)

**Published:** May 21, 2025

Our community has had a great time solving our _spot the mistakes_ challenges, so we thought we’d keep it rolling with another one.

This time, we’ll be setting our sights on CSS. See if you can spot the **6 mistakes** in our code.

**Let us know on socials if you spot them, or check out the answers at the end of the article.**

## The Code

    body {
      font-family: "Helvetica Neue", sans serif;
      background-colour: #f9f9f9;
      margin 0;
    }
    
    h1 {
      color: lightnavy;
      margin-top: 1em;
    }
    
    p {
      line-height: 150%;
      max-width: 600px
      font-size: 1.1rem;
      text-align: justified;
    }
    
    a {
      text-decoration: none;
      color: #00f;
      hover-color: red;
    }

## The Answers

Think you’ve found the answers? See if you found them all below.

  Mistake 1 

**Incorrect font family keyword**  
 The value `sans serif` is invalid—CSS requires a hyphen: `sans-serif`.

   Mistake 2 

**Incorrect property name**  
 `background-colour` is not valid CSS. The correct property is spelled `background-color`.

   Mistake 3 

**Missing colon in property**  
 The line `margin 0;` is missing a colon and should be `margin: 0;`.

   Mistake 4 

**Nonexistent CSS color name**  
 `lightnavy` might sound real, but it’s not a valid CSS color. Use something like `lightblue` or `#336699` instead.

   Mistake 5 

**Missing semicolon after property**  
 In the `p` selector, there's no semicolon after `max-width: 600px`. This breaks the next line `font-size` from being parsed correctly.

   Mistake 6 

**Invalid hover property syntax**  
 `hover-color` is not a real CSS property. To change color on hover, use a pseudo-class:  
  
`a:hover { color: red; }`

  



## Related Articles

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