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Ravi kumar
Ravi kumar

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CSS Box-Model

CSS box model is a container which contains multiple properties including borders, margin, padding and the content itself. The web browser renders every element as a rectangular box according to the CSS box model.

Box-Model has multiple properties in CSS. Some of them are given below:

  • content
  • padding
  • border
  • margin

Content area

The innermost rectangle, known as the content area, may contain text or other visual elements. It is bounded by the content edge and its dimensions are given by content box width and height. If the element is a block element, then the content edge can also be set with the min-width, max-width, min-height, max-height properties.
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If the box-sizing property is set to content-box, the content area's size can be explicitly defined with the width, min-width, max-width, height, min-height, and max-height properties

Padding area

Padding is the space between the border and content of an element. Padding is an important element in web design because it helps make content more visible and readable.

There are four padding properties,
padding-top
padding-right
padding-bottom
padding-left

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All the padding properties can be changed independently or a short hand padding property can be used to change all the values at once.
Short hand properties syntax:
padding: padding-top padding-right padding-bottom padding-left;

Border area

It is the area between the box’s padding and margin. Its dimensions are given by the width and height of border.
The borders are calculated by the border-width and shorthand border properties.
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Short hand border properties syntax :
border: border-width border-style border-color

If the box-sizing property is set to border-box, the border area's size can be explicitly defined with the width, min-width, max-width, height, min-height, and max-height properties

Margin area

The space around the elements can be set using the CSS margin properties.

There are four margin properties,
margin-top
margin-bottom
margin-left
margin-right

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In addition to the above four properties, we also have a short hand property called margin.
margin : margin-top margin-right margin-bottom margin-left;

Margin clears the area around an element the difference is that it takes care of the area outside the border.The margins are transparent and cannot have any background colors.

Calculating Overall dimensions

How to calculate the total width of the box,

The total width of the element would follow the following formula,
Total element width = width + padding-left + padding-right + border-left + border-right + margin-left + margin-right.
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How to calculate the total height of the box,

The total height of the element would follow the following formula
Total element height = height + padding-top + padding-bottom + border-top + border-bottom + margin-top + margin-bottom
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After spending some time and getting familiar with the basics of the CSS Box Model, it can be helpful in designing the layouts efficiently.

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