:nth-child(invalid) {}
:nth-child(2not) {}
:nth-child(2n+1 + 100) {}
:nth-child(2n+1 + 100 {}
:nth-child(2n + +1) {}
:nth-child(2n invalid +1) {}
:nth-child(2n + +1 {}
:nth-child(2n + not) {}
:nth-child(2n + not {}
:nth-child(even .div) {}
:nth-child(even .div {}
:nth-child(even of ^.div) {}
:nth-child(even of ^.div {}
:nth-child(even ^.div,) {}
:nth-child(even ^.div, {}
:nth-child(2 n) {}
:nth-child(2 n + 1) {}
:nth-child(2n + 1