To center 3 divs vertically and horizontally, use flexbox and align-items/justify-content properties.

• Wrap the 3 divs in a parent container

• Set the parent container's display property to flex

• Set the parent container's align-items and justify-content properties to center

Hidden input type is used during form submission

• is used to include data in form submission without displaying it to the user

• Commonly used for passing values like session tokens or tracking information

Block elements take up the full width available, while inline-block elements only take up as much width as necessary.

• Block elements start on a new line and stack vertically

• Inline-block elements can sit next to each other and wrap to a new line when necessary

• Block elements have a default width of 100%

• Inline-block elements have a default width of the content inside them

• Examples of block elements include

  ,

  -

  ,

  ,

  ,
  ,

  Examples of inline-block elements include , , ,

Use window.location.search or URLSearchParams to get URL params in JavaScript

• Use window.location.search to get the query string portion of the URL

• Use URLSearchParams to parse and extract individual parameters from the query string

• Example: const params = new URLSearchParams(window.location.search); const paramValue = params.get('paramName');

To add a background image, use CSS background-image property.

• Create a CSS class or ID for the element you want to add the background image to.

• Use the background-image property to specify the URL of the image.

• Set the background-size property to cover or contain the element.

• Example: .container { background-image: url('image.jpg'); background-size: cover; }

Flex is one-dimensional layout while Grid is two-dimensional layout.

• Flex is used for creating flexible and responsive layouts.

• Grid is used for creating complex and structured layouts.

• Flex is best suited for small-scale layouts while Grid is best suited for large-scale layouts.

• Flex is easier to learn and implement while Grid requires more advanced knowledge.

• Flex is supported by older browsers while Grid has limited support in older browsers.