sogo/UI/WebServerResources/scss/core/mixins.scss

@mixin margin-selectors($before:1em, $after:1em, $start:0px, $end:0px) {
  -webkit-margin-before: $before;
  -webkit-margin-after: $after;
  -webkit-margin-start: $start;
  -webkit-margin-end: $end;
}

@mixin not-selectable($value:none) {
  user-select: $value;
}

@mixin input-placeholder-color($color) {
  &::-webkit-input-placeholder,
  &::-moz-placeholder, /* Firefox 19+ */
  &:-moz-placeholder, /* Firefox 18- */
  &:-ms-input-placeholder {
    color: $color;
  }
}
// Utility to compensate for the the xml mandatory attribute values
// Creates classes extending layout attributes with no values
// ----------------------------------------------------------------
@mixin attributesToClasses($selectors) {
  @each $selector in $selectors {
    .md-#{$selector} {
// no syntax error here
      @extend [#{$selector}] !optional
    }
  }
}