Mons1eurEnzo

BX.ready(function () {
    var MyPanel = BX("navmenu"), // ID ShowPanel Bitrix
            BxPanel = BX.admin.panel,
            FxPanel = function () {
                if (window.pageYOffset >= BxPanel.DIV.clientHeight && BxPanel.isFixed() === false) {
                    MyPanel.style.top = 0;
                } else if (BxPanel.isFixed() === true) {
                    MyPanel.style.top = BxPanel.DIV.clientHeight + "px";
                } else {
                    MyPanel.style.top = BxPanel.DIV.clientHeight - window.pageYOffset + "px";