fix: post Dark mode fixes

frontend/src/features/fuel-logs/components/FuelLogForm.tsx

@@ -188,10 +188,16 @@ const FuelLogFormComponent: React.FC<{ onSuccess?: () => void; initial?: Partial
                 InputProps={{
                   readOnly: true,
                   sx: (theme) => ({
-                    backgroundColor: theme.palette.mode === 'dark' ? '#4C4E4D' : 'grey.50',
+                    backgroundColor: 'grey.50',
+                    ...theme.applyStyles('dark', {
+                      backgroundColor: '#4C4E4D',
+                    }),
                     '& .MuiOutlinedInput-input': {
                       cursor: 'default',
-                      color: theme.palette.mode === 'dark' ? '#F2F3F6' : 'inherit',
+                      color: 'inherit',
+                      ...theme.applyStyles('dark', {
+                        color: '#F2F3F6',
+                      }),
                     },
                   }),
                 }}

frontend/src/features/fuel-logs/components/StationPicker.tsx

@@ -333,7 +333,10 @@ export const StationPicker: React.FC<StationPickerProps> = ({
       sx={(theme) => ({
         '& .MuiAutocomplete-groupLabel': {
           fontWeight: 600,
-          backgroundColor: theme.palette.mode === 'dark' ? '#4C4E4D' : 'grey.100',
+          backgroundColor: 'grey.100',
+          ...theme.applyStyles('dark', {
+            backgroundColor: '#4C4E4D',
+          }),
           fontSize: '0.75rem',
           textTransform: 'uppercase',
           letterSpacing: '0.5px'