div {
  -webkit-user-select: none;  /* Chrome all / Safari all */
  -moz-user-select: none;     /* Firefox all */
  -ms-user-select: none;      /* IE 10+ */
  user-select: none;          /* Likely future */
  -webkit-touch-callout: none;
}
::selection { background: transparent; }
::-moz-selection { background: transparent; }