Color overlay with background image. `scale-color` - scss function. `$color` - predefined scss variable

color-overlay.scss

div {
  background: linear-gradient(0deg, scale-color($color, $alpha: -15%), scale-color($color, $alpha: -15%)), url(/assets/images/example.jpg) center / cover;
}

// or

div {
  box-shadow: inset 0 0 0 200vw scale-color($accent-blue-color, $alpha: -15%);
  background: url(/assets/images/example.jpg) center / cover;
}