fix: sidebar and body background not adapting to light mode

## Changes

### Sidebar
- Remove hardcoded `backgroundColor: "#000000"`
- Use `theme.palette.background.main` for dynamic theming
- Update border color to use `theme.palette.border.light`

### Body Background
- Remove hardcoded `background-color: #000000` from index.css
- Add GlobalStyles in App.jsx to apply theme background to body element

## Benefits
- Sidebar now properly displays in light mode
- Body background adapts correctly to theme changes
- Consistent theming across light and dark modes

client/src/App.jsx

@@ -22,9 +22,18 @@ function App() {
 		};
 	}, []);
 
+	const theme = mode === "light" ? lightTheme : darkTheme;
+
 	return (
-		<ThemeProvider theme={mode === "light" ? lightTheme : darkTheme}>
+		<ThemeProvider theme={theme}>
 			<CssBaseline />
+			<GlobalStyles
+				styles={{
+					body: {
+						backgroundColor: theme.palette.background.main,
+					},
+				}}
+			/>
 			<AppLayout>
 				<Routes />
 			</AppLayout>

client/src/Components/v1/Sidebar/index.jsx

@@ -84,8 +84,8 @@ const Sidebar = () => {
 			gap={theme.spacing(6)}
 			sx={{
 				transition,
-				backgroundColor: "#000000",
-				borderRight: "1px solid #344054",
+				backgroundColor: theme.palette.background.main,
+				borderRight: `1px solid ${theme.palette.border.light}`,
 				zIndex: 1000,
 			}}
 		>

client/src/index.css

@@ -6,7 +6,6 @@
 
 html,
 body {
-	background-color: #000000;
 	overscroll-behavior: none;
 }