feat: responsive ui above 640px (#1741)

tests/parallels/subpage.spec.ts

@@ -9,7 +9,7 @@ test.describe('subpage', () => {
     await openHomePage(page);
     await waitMarkdownImported(page);
     await page.getByTestId('sliderBar-arrowButton-collapse').click();
-    const sliderBarArea = page.getByTestId('sliderBar');
+    const sliderBarArea = page.getByTestId('sliderBar-inner');
     await expect(sliderBarArea).not.toBeVisible();
   });
 });