Angular Shadow DOM Component Encapsulation

Shadow DOM provides a powerful mechanism for component encapsulation, preventing styles and scripts from a component from leaking out and affecting the rest of the application, and vice versa. This challenge asks you to create a simple Angular component that utilizes Shadow DOM to encapsulate its internal styling and structure, demonstrating a fundamental aspect of component isolation. This is crucial for building robust and maintainable Angular applications.

Problem Description

You need to create an Angular component called ShadowCardComponent that renders a card with a title and a description. The component should utilize Shadow DOM to encapsulate its styling. This means that any styles defined within the component's template should not affect the styles of the parent component or any other elements outside the component. Conversely, styles from the parent component should not affect the styling of the ShadowCardComponent.

Key Requirements:

• Shadow DOM Usage: The component must be rendered within a Shadow DOM.
• Encapsulated Styling: Styles defined within the component's template (e.g., card background color, text color) should be isolated to the Shadow DOM and not bleed out.
• Input Properties: The component should accept two input properties: title (string) and description (string).
• Rendering: The component should render the title and description within the Shadow DOM.
• No External CSS: The component should not rely on external CSS files for its styling. All styling should be defined within the component's template using the style binding.

Expected Behavior:

When the ShadowCardComponent is used in a parent component, its styles should remain isolated. Changes to the parent component's styles should not affect the appearance of the card, and changes to the card's styles should not affect the parent component.

Edge Cases to Consider:

• What happens if the parent component attempts to style an element within the Shadow DOM using a CSS selector? (It should not work).
• How does Angular handle styling when using Shadow DOM? (Angular's view encapsulation is automatically enabled when using Shadow DOM).

Examples

Example 1:

Input: Parent Component Template:
<shadow-card [title]="'My Card'" [description]="'This is a description.'"></shadow-card>
Parent Component CSS:
.parent-class {
  background-color: lightblue;
}

Output:
A card with the title "My Card" and the description "This is a description." rendered within a Shadow DOM. The card's background color is defined within the ShadowCardComponent's template and is *not* affected by the parent component's `lightblue` background.

Explanation: The Shadow DOM encapsulation prevents the parent's background color from affecting the card's background.

Example 2:

Input: ShadowCardComponent Template:
<div class="card">
  <h2 class="card-title"></h2>
  <p class="card-description"></p>
</div>
<style>
  .card {
    background-color: lightgreen;
    padding: 10px;
  }
  .card-title {
    color: darkblue;
  }
  .card-description {
    font-style: italic;
  }
</style>

Output:
A card with a lightgreen background, darkblue title, and italic description, all rendered within the Shadow DOM.

Explanation: The styles are encapsulated within the Shadow DOM and do not affect the rest of the application.

Constraints

• Angular Version: Use Angular version 14 or higher.
• No External CSS: Do not use external CSS files. All styling must be done within the component's template using the style binding.
• Component Structure: The component must be a standard Angular component with an @Component decorator.
• Performance: The solution should be reasonably performant. Avoid unnecessary DOM manipulations.

Notes

• Angular automatically enables Shadow DOM encapsulation when the encapsulation property in the @Component decorator is set to ViewEncapsulation.ShadowDom.
• Consider using template variables to access elements within the Shadow DOM if needed.
• Focus on demonstrating the core concept of Shadow DOM encapsulation. The card design itself is not the primary focus.
• Ensure your component correctly renders the input title and description properties.