List NZ Postcodes

Nothing, to my way of thinking, is a better proof of a well ordered mind than a man's ability to stop just where he is and pass some time in his own company.
Seneca

:host()

The :host() CSS pseudo-class function selects the shadow host of the shadow DOM containing the CSS it is used inside (so you can select a custom element from inside its shadow DOM) — but only if the selector given as the function's parameter matches the shadow host.
:host() css reference