// Listen for back/forward navigation
window.addEventListener('popstate', (event) => {
  if (event.state) {
    console.log('Navigated to:', event.state);
    updateContent(event.state);
  }
});

// pushState does NOT fire popstate
history.pushState({ page: 1 }, '', '/page1');
// No popstate event fired

// Only browser back/forward triggers popstate
// Going back: popstate fires with { page: 1 }

// The state object passed to pushState/replaceState is available in popstate
window.addEventListener('popstate', (e) => {
  const state = e.state; // null if no state was set
  if (state) {
    console.log('Page:', state.page);
  }
});