$font-weights: ("thin":100,"extrlight":200,"light": 300,"regular": 400, "medium": 500,"semibold":600, "bold": 700,"extrabold":800,"black":900);

.selector{
font-weight: map-get($font-weights, thin);
}

@mixin prefix($declarations, $prefixes: ()) {
  @each $property, $value in $declarations {
    @each $prefix in $prefixes {
      #{'-' + $prefix + '-' + $property}: $value;
    }

    // Output standard non-prefixed declaration
    #{$property}: $value;
  }
}

.selector {
  @include prefix((
    column-count: 3,
    column-gap: 1.5em,
    column-rule: 2px solid hotpink
  ), webkit moz);
}

$bp: (
  mobile: 480px,
  tablet: 768px,
  desktop: 1440px
);

@mixin query($display) {
  @each $key, $value in $bp {
    //  defining min-width
    @if ($display == $key) {
      @media (min-width: $value) {
        @content;
      }
    }
  }
}

.selector{
  display: flex;
  @include query(mobile) {
    flex-direction: column;

    // you can pick any value you wish.
    height: 500px;
  }
}