message: [improvement] Color: update neutral color variables
diff: @orange-dark: #ed6a0c;
  @orange-light: #fffbe8;
  @green: #4b0;
  -@gray: #c9c9c9;
  +@gray: #c8c9cc;
  @gray-light: #e5e5e5;
  @gray-darker: #7d7e80;
  -@gray-dark: #999;
  +@gray-dark: #969799;
  // default colors
  -@text-color: #333;
  -@border-color: #eee;
  +@text-color: #323233;
  +@border-color: #ebedf0;
  @active-color: #e8e8e8;
  @background-color: #f8f8f8;
  @background-color-light: #fafafa;
  