@namespace url(http://css.example.net/);
 tests, tests * { display: block; color: green; }
 testA[|attribute] { color: red; }
 testB[|attribute="fail"] { color: red; }
 testC[|attribute~="fail"] { color: red; }
 testD[|attribute^="fail"] { color: red; }
 testE[|attribute*="fail"] { color: red; }
 testF[|attribute$="fail"] { color: red; }
 testG[|attribute|="fail"] { color: red; }