$indentLevels: 'Zero', 'One', 'Two', 'Three', 'Four', 'Five', 'Six';

@mixin indent_blocks_fixed($depth) {
  margin-inline-start: #{$depth * 40}px !important;
}

@each $indentLevel in $indentLevels {
  $i: index($indentLevels, $indentLevel) - 1;
  .indent#{$indentLevel} {
    @include indent_blocks_fixed($i);
  }
}