The role of vw and vh in css

Viewport units vw and vh are used to set element size and position according to the browser window viewport size, providing responsiveness, consistency, and ease of use.

The role of vw and vh in CSS

Short answer:
vw and vh are viewport units in CSS, used to set element size and position based on the viewport size of the browser window.

Detailed explanation:

What are viewport units?
Viewport units are a CSS unit that calculates the size and position of an element based on the browser's viewport dimensions, regardless of device or screen size.

vw and vh

• vw (viewport width): represents the percentage of the viewport width (horizontal direction). For example, 1vw is equal to 1% of the viewport width.
• vh (viewport height): represents the percentage of the viewport height (vertical direction). For example, 1vh is equal to 1% of the viewport height.

How to use vw and vh
vw and vh are often used to create fluid responsive layouts, which means that as the browser window changes size, the size of the elements changes. The size and position will be adjusted accordingly. For example:

.container {
  width: 50vw;
  height: 50vh;
}

This CSS code creates a container element with a width half the viewport width and a height half the viewport height.

Advantages:
Advantages of using vw and vh include:

• Responsiveness: Adjust elements according to the browser window size size and position to provide a responsive design.
• Consistency: Maintain a consistent user interface across a variety of devices and screen sizes.
• Simplicity: Easy to use, no complex calculations or media queries required.

Things to note:
Although vw and vh provide an easy way to build responsive layouts, there are also things to note:

• Nested elements: The size and position of internal elements are also affected by the vw/vh value of the parent element.
• Mixed Units: Avoid mixing vw/vh with other unit types such as percentages or pixels, as this may lead to unexpected layouts.
• Browser support: Most modern browsers support vw and vh, but polyfills may be required in older browsers for compatibility.

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