✨ Added a background image input

Added an input in the advanced options for a background image. Also removed an unused import from my previous commit and changed the margin on the header bar to padding instead.

src/components/layout/Background.tsx

@@ -0,0 +1,19 @@
+import { Global } from '@mantine/core';
+import { useConfig } from '../../tools/state';
+
+export function Background() {
+  const { config } = useConfig();
+
+  return (
+    <Global
+      styles={{
+        body: {
+          backgroundImage: `url('${config.settings.background}')` || '',
+          backgroundPosition: 'center',
+          backgroundSize: 'cover',
+          backgroundRepeat: 'no-repeat',
+        },
+      }}
+    />
+  );
+}