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CSS Sass Basics Add Reusable Logic to Your Sass Storing Values in Maps

Melissa L
Melissa L
Front End Web Development Techdegree Student 9,672 Points

Mixin media query error: Invalid null operation: "null lt 576px".

Not sure why it is giving this message in the console. The error message is: error scss/utilities/_mixins.scss (Line 48: Invalid null operation: "null lt 576px".).

Any help will be greatly appreciated.


@mixin mq($break) {
  $value: map-get($breakpoints, $break);
  $sm: map-get($breakpoints, 'sm');

  @if $value < $sm {               /* this is line 48 */
    @media (max-width: $value) { 
  @else {
    @media (min-width: $value) {



  'xs':   575px,  
  'sm':   576px,
  'med':  768px,
  'lg':   992px,