Prevent saving images for copyright purposes

image.html

<img class='portfolio' oncontextmenu="return false" ondragstart="return false" src='copyrighted_image.png' />

styles.css

img.portfolio{
  -moz-user-select: none;
  -khtml-user-select: none;
  -webkit-user-select: none;
  -o-user-select: none;
}