Sass/Scss Map

$spacer: 1rem !default;$spacers: () !default;$spacers: map-merge(  (    0: 0,    1: $spacer * .25,    2: $spacer * .5,    3: $spacer,    4: $spacer * 1.5,    5: $spacer * 3,  ),  $spacers);

.test-mt-5 {  margin-top: map-get($spacers, 5);}

@each $key, $value in $spacers {  .test-mt-#{$key} {    margin-top: $value;  }}