:root {
    --z-index-behind: -1;
    --z-index-bar-lines: 1;
    --z-index-bar-wrapper: 1;
    --z-index-scale-chart: 2;
    --z-index-bar-links: 2;
    --z-index-bar-links-highlight: 3;
    /* Above the highlighted links, which are meant to cover the chart's content but not the
       controls on it: a link crossing a hovered bar must not swallow its link radio buttons. */
    --z-index-bar-radio: 4;
    /* The frozen heading bands of a Configuration Matrix. They stack among the module's
       blocks - the grid carries no z-index of its own - so they sit above the bar layers
       a scale chart in the same module brings. */
    --z-index-matrix-band: 5;
    --z-index-matrix-corner: 6;
    --z-index-main-root: 100;
    --z-index-fixed-root: 200;
    --z-index-scrollbar: 100;
    --z-index-focus-field: 500;
    --z-index-docked-panel: 600;
    --z-index-overlay: 1000;
    --z-index-custom-dialog-container: 1300;
    --z-index-server-dialog: 1400;
    /* A confirm box answers the user's click, which may come from inside a server dialog. */
    --z-index-confirm-dialog: 1500;
    --z-index-tooltip-module: 1600;
    --z-index-listbox-module: 1800;
    --z-index-context-menu: 1900;
    --z-index-search-module: 2000;
    --z-index-tooltip: 2400;

    --z-index-top-element: 15000;
    --z-index-global-overlay-element: 20000; 
    --z-index-global-error: 999999;
}