freeCodeCamp/curriculum/challenges/english/03-front-end-development-libraries/sass/use-if-and-else-to-add-logic-to-your-styles.md

id, title, challengeType, forumTopicId, dashedName

id	title	challengeType	forumTopicId	dashedName
587d7dbe367417b2b2512bb8	Use @if and @else to Add Logic To Your Styles	0	301463	use-if-and-else-to-add-logic-to-your-styles

--description--

The @if directive in Sass is useful to test for a specific case - it works just like the if statement in JavaScript.

@mixin make-bold($bool) {
  @if $bool == true {
    font-weight: bold;
  }
}

And just like in JavaScript, @else if and @else test for more conditions:

@mixin text-effect($val) {
  @if $val == danger {
    color: red;
  }
  @else if $val == alert {
    color: yellow;
  }
  @else if $val == success {
    color: green;
  }
  @else {
    color: black;
  }
}

--instructions--

Create a mixin called border-stroke that takes a parameter $val. The mixin should check for the following conditions using @if, @else if, and @else:

light - 1px solid black
medium - 3px solid black
heavy - 6px solid black

If $val is not light, medium, or heavy, the border should be set to none.

--hints--

Your code should declare a mixin named border-stroke which has a parameter named $val.

assert(code.match(/@mixin\s+?border-stroke\s*?\(\s*?\$val\s*?\)\s*?{/gi));

Your mixin should have an @if statement to check if $val is light, and to set the border to 1px solid black.

assert(
  code.match(
    /@if\s+?\$val\s*?===?\s*?light\s*?{\s*?border\s*?:\s*?1px\s+?solid\s+?black\s*?;\s*?}/gi
  )
);

Your mixin should have an @else if statement to check if $val is medium, and to set the border to 3px solid black.

assert(
  code.match(
    /@else\s+?if\s+?\$val\s*?===?\s*?medium\s*?{\s*?border\s*?:\s*?3px\s+?solid\s+?black\s*?;\s*?}/gi
  )
);

Your mixin should have an @else if statement to check if $val is heavy, and to set the border to 6px solid black.

assert(
  code.match(
    /@else\s+?if\s+?\$val\s*?===?\s*?heavy\s*?{\s*?border\s*?:\s*?6px\s+?solid\s+?black\s*?;\s*?}/gi
  )
);

Your mixin should have an @else statement to set the border to none.

assert(code.match(/@else\s*?{\s*?border\s*?:\s*?none\s*?;\s*?}/gi));

--seed--

--seed-contents--

<style type='text/scss'>



  #box {
    width: 150px;
    height: 150px;
    background-color: red;
    @include border-stroke(medium);
  }
</style>

<div id="box"></div>

--solutions--

<style type='text/scss'>
  @mixin border-stroke($val) {
    @if $val == light {
      border: 1px solid black;
    }
    @else if $val == medium {
      border: 3px solid black;
    }
    @else if $val == heavy {
      border: 6px solid black;
    }
    @else {
      border: none;
    }
  }


  #box {
    width: 150px;
    height: 150px;
    background-color: red;
    @include border-stroke(medium);
  }
</style>

<div id="box"></div>