// Bad: div as button
<div onClick={handleClick}>Submit</div>

// Good: semantic button
<button onClick={handleClick}>Submit</button>

// Bad: image without alt in Next.js
<Image src="/hero.jpg" width={800} height={400} />

// Good: image with alt
<Image src="/hero.jpg" width={800} height={400} alt="Team collaborating in a modern office" />

// Bad: no focus management on route change
useEffect(() => {
  // nothing
}, [location]);

// Good: focus management on route change
useEffect(() => {
  const mainContent = document.getElementById('main-content');
  if (mainContent) {
    mainContent.focus();
    mainContent.scrollIntoView();
  }
}, [location]);

// Bad: link opening new tab
<a href={url} target="_blank">Resource</a>

// Good: link with new tab warning
<a href={url} target="_blank" rel="noopener noreferrer">
  Resource <span className="sr-only">(opens in new tab)</span>
</a>

<!-- Bad: v-if on live region -->
<div v-if="message" aria-live="polite">{{ message }}</div>

<!-- Good: v-show keeps element in DOM -->
<div v-show="message" aria-live="polite">{{ message }}</div>

<!-- Bad: no focus after transition -->
<transition name="fade">
  <div v-if="showModal" class="modal">...</div>
</transition>

<!-- Good: focus managed after transition -->
<transition name="fade" @after-enter="focusModal">
  <div v-if="showModal" ref="modal" class="modal" tabindex="-1">...</div>
</transition>

// Bad: ARIA binding
<button [aria-label]="label">X</button>

// Good: ARIA attribute binding
<button [attr.aria-label]="label">X</button>

// Bad: ngFor without trackBy
<li *ngFor="let item of items">{{ item.name }}</li>

// Good: ngFor with trackBy
<li *ngFor="let item of items; trackBy: trackById">{{ item.name }}</li>

// Route change announcements
constructor(private liveAnnouncer: LiveAnnouncer, private router: Router) {
  this.router.events.pipe(
    filter(event => event instanceof NavigationEnd)
  ).subscribe((event: NavigationEnd) => {
    this.liveAnnouncer.announce(`Navigated to ${this.getPageTitle()}`);
  });
}

<!-- Bad: click on div -->
<div on:click={toggle}>Toggle</div>

<!-- Good: keyboard accessible -->
<button on:click={toggle}>Toggle</button>

<!-- Bad: animation without motion preference -->
<div transition:fly={{ y: 200 }}>Content</div>

<!-- Good: respects motion preference -->
<div transition:fly={{ y: reducedMotion ? 0 : 200, duration: reducedMotion ? 0 : 300 }}>Content</div>

<script>
  const reducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
</script>

<!-- Bad: no focus indicator -->
<button class="bg-blue-500 text-white px-4 py-2 rounded outline-none">
  Submit
</button>

<!-- Good: visible focus indicator -->
<button class="bg-blue-500 text-white px-4 py-2 rounded focus:outline-none focus-visible:ring-2 focus-visible:ring-blue-500 focus-visible:ring-offset-2">
  Submit
</button>

<!-- Bad: low contrast -->
<p class="text-gray-400">Important information</p>

<!-- Good: adequate contrast -->
<p class="text-gray-700">Important information</p>

<!-- Bad: animation without motion preference -->
<div class="transition-transform duration-300 hover:scale-105">Card</div>

<!-- Good: respects motion preference -->
<div class="transition-transform duration-300 hover:scale-105 motion-reduce:transition-none motion-reduce:hover:scale-100">Card</div>