CSS Humor

.wife {
  right: 100%;
  margin: 0;
}

From José

@import Windows
#BSOD {
  color: blue;
  content: "IRQL_NOT_LESS_OR_EQUAL";
  frequency: 10000Hz;
  text-color: white;
}

From Luís

.metalhead { color: #666; }

From nonox

#moon {
  backface-visibility: hidden;
}

From darxide

#flat-earth {
  width: 6371km;
  height: 6371km;
  border-radius: 50%;
}

From darxide

.roses { color: red; }
.violets { color: blue; }
#noticed .violets { content: "Why are they called violets if they are blue?"; }

From A. Jones

.glass.apple-campus { opacity: 0.00001; }

From @lipsumar

#bigbang { animation-delay: -13.8E9yrs; }

From @g16n

.ideal-man { creeping: 0; respect: 100; }

From @elisegraham

#Barcelona {
  display: grid;
  grid-auto-rows: 100px;
  grid-auto-columns: 100px;
}

From @praveenpuglia