message: [improvement] Toast: update background color
diff: @toast-text-color: @white;
  @toast-line-height: 20px;
  @toast-border-radius: 4px;
  -@toast-background-color: rgba(0, 0, 0, .7);
  +@toast-background-color: rgba(@text-color, .88);
  @toast-icon-size: 48px;
  @toast-text-min-width: 96px;
  @toast-text-padding: 8px 12px;
  