Angular Animations: Smooth UI Transitions

Animations improve user experience when used with purpose, like:
- dropdown open/close
- accordion expand
- page transition

## Step 1: Install animations module (if needed)

In modern Angular, ensure animations are enabled via providers:
`provideAnimations()`

## Step 2: Basic fade animation

```ts
import { Component } from '@angular/core';
import { trigger, transition, style, animate } from '@angular/animations';

@Component({
  selector: 'app-fade',
  standalone: true,
  animations: [
    trigger('fade', [
      transition(':enter', [
        style({ opacity: 0 }),
        animate('200ms', style({ opacity: 1 })),
      ]),
      transition(':leave', [
        animate('200ms', style({ opacity: 0 })),
      ]),
    ]),
  ],
  template: `
    <button (click)="toggle()">Toggle</button>
    <p *ngIf="show" @fade>Now you see me</p>
  `,
})
export class FadeComponent {
  show = true;
  toggle() {
    this.show = !this.show;
  }
}
```

## Keep animations professional

- fast and subtle
- do not animate everything
- prefer simple transitions

> Next: Internationalization (i18n) and localization patterns.