@map: {
  @width: 400px;
  @colors: {
    toolbar-background: red;
    toolbar-foreground: white;
  }
};

#ns {
  .mixin() {
    @height: 200px;
  }
}

@breakpoints: {
  mobile: 320px;
  tablet: 768px;
  desktop: 1024px;
};

@media (min-width: @breakpoints[mobile]) {
  .toolbar {
    width: @map[@width];
    height: #ns.mixin[@height];
    background: @map[@colors][toolbar-background];
    color: @map[@colors][toolbar-foreground];
  }
}