div span {
  moo: goo; }

foo {
  blah: blah; }
  foo goo {
    blee: blee;
    hello: world; }
    foo goo hoo {
      mux: scooba-dee-doo;
      flux: gooboo boo; }
      foo goo hoo d {
        inside: d now; }
  foo blux {
    hey: another thing;
    ho: will this work; }