consul/ui/packages/consul-ui/app/components/secret-button/layout.scss

%secret-button {
  cursor: pointer;
}
%secret-button input {
  display: none;
}
%secret-button input ~ em {
  visibility: hidden;
  font-style: normal;
}
%secret-button input:checked ~ em {
  @extend %user-select-text;
  visibility: visible;
  cursor: auto;
}
%secret-button input ~ em::before {
  display: inline;
  visibility: visible;
  content: '■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■';
}
%secret-button input:checked ~ em::before {
  display: none;
}