diff --git a/src/components/RightMenu/RightMenu.tsx b/src/components/RightMenu/RightMenu.tsx
index b3bb31ae0b9868cee7f5197029aa74b5ed7cf3fd..383754b6c80e913b06b9aea38dbf34905031378e 100644
--- a/src/components/RightMenu/RightMenu.tsx
+++ b/src/components/RightMenu/RightMenu.tsx
@@ -4,20 +4,21 @@ import * as React from "react";
 import { RightMenuProps } from "./RightMenuProps";
 import "./RightMenu.scss";
 const RightMenu: React.FC<RightMenuProps> = (props: RightMenuProps) => {
-  const { items, width } = props;
-  const [selectedItem, setSelectedItem] = React.useState<number>(0);
-  const handleChangeSelectedItem = (newIndex: number) =>
-    setSelectedItem(newIndex);
+  const { items, width, selectedItemProp:selectedItem=0 } = props;
+  //const [selectedItem, setSelectedItem] = React.useState<number>(selectedItemProp);
+/*   const handleChangeSelectedItem = (newIndex: number) =>
+    setSelectedItem(newIndex); */
   const handleClickAnchor = (
     e: React.MouseEvent<HTMLAnchorElement, MouseEvent>,
     onClick: Function | undefined,
     id: number
   ) => {
     onClick?.();
-    handleChangeSelectedItem(id);
+    //handleChangeSelectedItem(id);
   };
   return (
     <List
+    className="section-container"
       sx={{ width: "100%", maxWidth: width, bgcolor: "background.paper" }}
       component="nav"
       aria-labelledby="nested-list-subheader"
diff --git a/src/components/RightMenu/RightMenuProps.ts b/src/components/RightMenu/RightMenuProps.ts
index 2d1388457084692f249fd44c1fc25f78537f623b..f2818b8f502581f4761e64f68199e09dc59a8ad1 100644
--- a/src/components/RightMenu/RightMenuProps.ts
+++ b/src/components/RightMenu/RightMenuProps.ts
@@ -10,4 +10,5 @@ export interface RightMenuProps {
     items: RightMenuItem[];
     width: string;
     baseUrl?: string;
+    selectedItemProp?:number;
 }
\ No newline at end of file
diff --git a/src/components/layout-pages/MainContentContainer.jsx b/src/components/layout-pages/MainContentContainer.jsx
index 3d54657ec59e79cf903cf8fccf8963a5e7cb411b..2995cd30e424b75fdb7e0e2815b6635e42696d55 100644
--- a/src/components/layout-pages/MainContentContainer.jsx
+++ b/src/components/layout-pages/MainContentContainer.jsx
@@ -4,6 +4,7 @@ import * as React from "react";
 const MainContentContainer = ({ children }) => {
   return (
     <Box
+   
       sx={{
         overflow: "hidden",
         boxSizing: "border-box",
@@ -15,10 +16,12 @@ const MainContentContainer = ({ children }) => {
       }}
     >
       <Box
+      // className="section-container"
         sx={{
           boxSizing: "border-box",
           width: "100%",
           //backgroundColor:"grey"
+          
         }}
       >
         {children}
diff --git a/src/pages/demo/FileMosaicDemoPage.jsx b/src/pages/demo/FileMosaicDemoPage.jsx
index a2b4910aedd4a60775591822b06731064e1d0ad4..25fb74648448a7879c79b3e5a0bc96e5fa4ce55d 100644
--- a/src/pages/demo/FileMosaicDemoPage.jsx
+++ b/src/pages/demo/FileMosaicDemoPage.jsx
@@ -31,6 +31,80 @@ import DemoFileMosaicSmartImgFit from "../../components/demo-components/filemosa
 import CodeJSFileMosaicSmartImgFit from "../../components/demo-components/filemosaic-demo/CodeJSFileMosaicSmartImgFit";
 
 const FileMosaicDemoPage = (props) => {
+  const [selectedItem, setSelectedItem] = React.useState(0);
+
+  const scrollHandler = () => {
+    let menu = document.querySelector(".section-container");
+
+    const rightMenuItemsWithIdSec = rightMenuItems.map((x) => {
+      return {
+        ...x,
+        idSec: x.referTo.split("#")[1],
+      };
+    });
+    /*  console.log(
+      "scrollHandler rightMenuItemsWithIdSec",
+      rightMenuItemsWithIdSec.map((x) => x.idSec)
+    ); */
+    const arrElements = rightMenuItemsWithIdSec.map((x) => {
+      return { ...x, element: document.getElementById(x.idSec) };
+    });
+
+    //console.log("scrollHandler arrElements", arrElements);
+    let pos_menu = window.pageYOffset + menu.offsetHeight;
+
+    //simply chech whicof them is clser to offset toip????
+    console.log("scrollHandler pos_menu", pos_menu);
+
+    const arrElementsEnhanced = arrElements.map((x) => {
+      const element = x.element;
+      const postElement = element.offsetTop + element.offsetHeight;
+      const distance = Math.abs(postElement - pos_menu);
+      return { ...x, distance };
+    });
+
+    console.log(
+      "scrollHandler distances",
+      pos_menu,
+      arrElementsEnhanced.map(({ distance }) => distance)
+    );
+
+    let min = Math.min(...arrElementsEnhanced.map((x) => x.distance));
+
+    arrElementsEnhanced.forEach((x) => {
+      if (x.distance === min) {
+        setSelectedItem(x.id);
+        console.log("foundelement distance", x.distance);
+        console.log("foundelement id", x.id);
+      }
+    });
+
+    console.log(
+      "distance min",
+      min,
+      arrElementsEnhanced.map((x) => x.distance)
+    );
+
+    // if (min === distance_A) setSelectedItem(0);
+    //document.querySelectorAll(".Menu .Item")[0].classList.add("Highlight");
+    // if (min === distance_B) setSelectedItem(1);
+    // if (min === distance_C) setSelectedItem(2);
+    /*  if (min === distance_B)
+      document.querySelectorAll(".Menu .Item")[1].classList.add("Highlight");
+    if (min === distance_C)
+      document.querySelectorAll(".Menu .Item")[2].classList.add("Highlight"); */
+  };
+  React.useEffect(() => {
+    console.log("scrollHandler container");
+
+    window.addEventListener("scroll", scrollHandler);
+
+    return () => {
+      console.log("foundelement","removing event");
+      window.removeEventListener("scroll", scrollHandler);
+    };
+  }, []);
+
   return (
     <React.Fragment>
       <MainContentContainer>
@@ -79,7 +153,10 @@ const FileMosaicDemoPage = (props) => {
             <CodeHighlight>{`<FileInputButton/>`} </CodeHighlight>
             component for allowing the user to select files. For further
             information of this component check out the{" "}
-            <AnchorToTab href="/components/fileinputbutton">FileInputButton</AnchorToTab> page.
+            <AnchorToTab href="/components/fileinputbutton">
+              FileInputButton
+            </AnchorToTab>{" "}
+            page.
           </Alert>
           <br />
           <Alert severity="info">
@@ -392,12 +469,17 @@ const FileMosaicDemoPage = (props) => {
         </section>
       </MainContentContainer>
       <RightMenuContainer>
-        <RightMenu width="240px" items={rightMenuItems} />
+        <RightMenu
+          width="240px"
+          items={rightMenuItems}
+          selectedItemProp={selectedItem}
+        />
       </RightMenuContainer>
     </React.Fragment>
   );
 };
 export default FileMosaicDemoPage;
+
 const rightMenuItems = [
   {
     id: 0,