Use @if and @else to Add Logic To Your Styles {can't find my mistake}

Tell us what’s happening:
Can’t seem tp phatom what’s wrong with my code that’s inhibiting me from progressing.

Your code so far

<style type='text/sass'>
  @mixin border-stroke ($val) {

   @if $val == light {
    border-stroke: 1px solid black;
   @else if $val == medium {
    border-stroke: 3px solid black;
   @else if $val == heavy {
    border-stroke: 6px solid black;
   @else $val == none {
    border-stroke: no border;

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

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

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Link to the challenge:

first else $val == none cannot work without if, second the no border is confusing. if you have some lint or go to w3 you find out the parameter is just none.

@mixin border-stroke($val){
@if $val == light{
border-stroke:1px solid black;
@else if $val == medium {
border:3px solid black;
@else if $val == heavy{
border:6px solid black;
@else {

Hope it is helpful for U