fix breakpoints

lib/hooks/useIsMobile.tsx

+import { useBreakpointValue } from '@chakra-ui/react';
+
+export default function useIsMobile() {
+  return useBreakpointValue({ base: true, lg: false });
+}

theme/foundations/breakpoints.ts

 const breakpoints = {
+// maybe we need them in future
+//   sm: '320px',
+//   md: '768px',
   lg: '1000px',
+  // these breakpoints are needed just to make "lg" work
+  xl: '2000px',
+  '2xl': '3000px',
 };
 
 export default breakpoints;