fixed some small design bugs

src/components/Files/TreeViewFiles.js

         aria-label="rich object"
         defaultCollapseIcon={<ExpandMoreIcon />}
         defaultExpandIcon={<ChevronRightIcon />}
-        sx={{ flexGrow: 1, overflowY: "auto" }}
+        sx={{
+          flexGrow: 1,
+          overflowY: "auto",
+          zIndex: 100000,
+          position: "relative",
+        }}
       >
         {renderTree(category)}
       </TreeView>

src/pages/FilesPage/AddFile.js

               <img src={uploadIcon} />
               <div className="uploadCV-input-sub-container">
                 {pdfFile !== null ? (
-                  <p>{pdfFile.name}</p>
+                  <p style={{ maxWidth: "80%" }}>{pdfFile.name}</p>
                 ) : (
                   <>
                     <p>