saas-one/frontend/operation-web/ext/modern/theme-material/sass/etc/mixins/shadows.scss

// shadows are slightly shifted left and down, this is a fix for toolbars that are next to each other horizontally
// or on top of each other vertically
// So the shadow from the bar on the left/bottom will not overlap the one on the right/top
$material-shadow-1: dynamic(2px 2px 5px 0 rgba(0, 0, 0, 0.12), 2px 2px 5px 0 rgba(0, 0, 0, 0.08));
$material-shadow-2: dynamic(2px 2px 5px 0 rgba(0, 0, 0, 0.18), 2px 2px 5px 0 rgba(0, 0, 0, 0.12));
$material-shadow-3: dynamic(2px 2px 5px 0 rgba(0, 0, 0, 0.21), 2px 2px 6px 0 rgba(0, 0, 0, 0.18));
$material-shadow-4: dynamic(2px 2px 6px 0 rgba(0, 0, 0, 0.25), 2px 2px 7px 0 rgba(0, 0, 0, 0.21));

@mixin material-shadow($level: 1, $index: null) {
    @if $level == 1 {
        box-shadow: $material-shadow-1;
    } @else if $level == 2 {
        box-shadow: $material-shadow-2;
    } @else if $level == 3 {
        box-shadow: $material-shadow-3;
    } @else if $level == 4 {
        box-shadow: $material-shadow-4;
    } @else {
        box-shadow: none;
    }

    @if ($level >= 1) {
        @if ($index) {
            z-index: #{$index};
        } @else {
            z-index: #{$level};
        }
    }
}