bigbluebutton-Github/bigbluebutton-html5/imports/ui/stylesheets/mixins/focus.scss

@mixin elementFocus($color: var(--color-primary)) {
  &:focus {
    outline: none;
    box-shadow: inset 0 0 0 var(--border-size-large) $color;
    border-radius: var(--border-size);
  }
}

@mixin inputFocus($shadow, $color: var(--color-primary)) {
  &:focus {
    outline: none;
    border-radius: var(--border-size);
    box-shadow: 0 0 0 var(--border-size) $shadow, inset 0 0 0 1px $color;
  }
}