Several concepts of CSS:
Containing block: the "layout context" of an element. For an element in normal HTML text flow, the containing block consists of the content edge of the nearest block-level ancestor, table cell, or inline block ancestor. Consider the following markup
<body> <div> <p>This is a paragraph.</p> </div></body>
The containing block of the p element is a div element because as a block element, table cell, or inline block element, this is the closest Ancestor elements. Similarly the containing block of a div is the body.
Non-replacement element: If the content of the element is included in the document, it is called a replacement element. For example: If the text content of a paragraph is placed in the element's own province, the paragraph is a non-replacement element.
Replacement element : This refers to an element that serves as a placeholder for other content. A classic example of a replacement element is the img element, which simply points to an image file that will be inserted into the document stream at the location of the img element itself. Most form elements can also be replaced (e.g. ).
Block-level elements : refers to elements such as paragraphs, titles, or divs. When these elements are in the normal flow, a 'line break' will be generated in their box and box primary key, so the block-level elements in the normal flow will be placed vertically. By declaring display:block, the element can generate a block-level box.
Inline elements : This refers to elements such as strong or span. These elements do not generate "line separators" before or after them. They are descendants of block-level elements by declaring display. :inline allows the element to generate an inline box. The root element
is the HTML element located at the top of the document tree. >Copyright Statement: This article is an original article by the blogger and may not be reproduced without the blogger's permission.
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