::before

h1

 ::before set to the background colour

h1

::after

 ::before set to the background colour

h1

mix-blend-mode

https://caniuse.com/#search=mix-blend-mode

text-fill-color

background-clip

https://www.microsoft.com/typography/otspec/fvar.htm

https://www.microsoft.com/typography/otspec/fvar.htm

Variable fonts

clip-path