updated code
bg{animation:bd 20s infinite}
bg{background-color:rgba(88,88,88,.6)} /* For Dark Appearance */
bg{background-color:rgba(170,170,170,.6)} /* For Light Appearance */
@keyframes bd{0%,100%{-webkit-backdrop-filter:blur(36px) contrast(250%) invert(20%)}}
if anybody get more native look with different values. please post here, because macos use different settings on lighter and darker backgrounds