Selector :host is one of the interesting and important topics in CSS, especially when working with web components. If you have worked with web components, you will definitely notice that one of their main characteristics is their encapsulated nature. Typically, web components are self-contained and create a shadow DOM that allows them to isolate their styles. However, selector :host allows us to modify these styles from within the component itself.
In general, selector :host is used for targeting the root shadow DOM element and provides the ability to implement stylish and user-friendly designs for applications that you create. Take an example to better understand this topic. Imagine that we have a custom component for displaying user profiles and we want to change some of its shadow DOM styles.
For a better understanding of selector :host, let's look at a simple example. In web components that are created, the source codes of CSS can be externally referenced. :host is used for applying these styles to the main component structure and can lead to changes in the styles of the components that are distinctly separate from the native shadow DOM and the main DOM.
This way allows us to implement many custom styles with unique user experiences that not only look beautiful but are also functional and can be used in different projects. Allow us to provide you with complete information on this topic.
Example Code
<template>
<style>
:host {
display: block;
background-color: #f1f1f1;
padding: 16px;
border-radius: 10px;
}
</style>
<div>
<p>This is a custom element.</p>
</div>
</template>Explanation Line by Line Code
<template> | Starts the template that defines the base structure of the component.<style> | The style section of the component that contains its CSS rules.:host | Specific selector for styling the host element or root component.display: block; | Configures the component to be displayed as a block to capture the complete space in the line.background-color: #f1f1f1; | Sets the background color of the component to a light gray shade.padding: 16px; | Adds internal spacing for a more aesthetically pleasing and suitable environment.border-radius: 10px; | Rounds the corners of the component for a soft and user-friendly design.<div> | A section that holds the inner content of the component.<p>This is a custom element.</p> | The text of the example, indicating a simple message inside the component.</template> | Ends the template declaration.