Assistance with adding blur transparency effect instead of regular transparency

Currently, my theme uses regular transparency effect for the Home Assistant background header :


app-header-background-color: rgba(32, 49, 73, 0.9)

QUESTION: I’m curious how I can change the background header transparency above to use blur transparency;

…similar to the effect when we use the below code for blurring the background behind popups:

dialog-backdrop-filter: blur(5px)
iron-overlay-backdrop-opacity: 1
iron-overlay-backdrop-background-color: rgba(0, 0, 0, 0.32)