CSS3: Cách cấm bôi đen, copy bằng CSS

<style>
  body{
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    -o-user-select: none;
    user-select: none;
  }
</style>