@superflycss/utilities-layout/dimension/zindex.css

Layout utilities

/** @define utilities */
@import "@superflycss/variables-dimension";
@each $type in zindex-dropdown-backdrop, zindex-navbar, zindex-dropdown, zindex-fixed, zindex-modal-backdrop, zindex-modal, zindex-popover, zindex-tooltip {
  .u-$(type) {
    z-index: var(--$(type)) !important;
  }
}