The background-blend-mode CSS property describes how the element's background images should blend with each other and the element's background color.
Blending modes should be defined in the same order as the background-image CSS property. If the blending modes' and background images' list lengths are not equal, it will be repeated and/or truncated until lengths match.
the unique non-ambiguous order defined by the formal grammar
/* One value */
/* Two values, one per background */
background-blend-mode: darken, luminosity;
/* Global values */
Is a <blend-mode> denoting the blending mode to be applied. There can be several values, separated by commas.