Introduction to CSS box model

What is CSS box model? The CSS box model is to allow us to fully understand the positioning function of the p+css model. The box model is a model that must be learned when learning the p+css layout method

1. What is CSS?

CSS (Cascading Style Sheet): Cascading style sheet is a language that separates the content and style of a web page, that is, designing web pages in aspx or html content, setting the style of the web page in CSS, etc.

2. What is the CSS box model?

Commonly heard names of attributes in web design: content, padding, border , border (margin), the CSS box model all has these attributes. These properties are the same as those of boxes in our daily lives. The content refers to the contents of the box; the filling refers to the anti-seismic materials added to avoid damage to the contents of the box; the frame refers to the box itself; as for the boundary, it means that a certain gap should be left between the boxes to maintain ventilation. 3. Two types of box models

1. Standard box model

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#2. IE box model

                       These two pictures are exactly the same, but when you look carefully, you will find the similarities and differences between them. Both box models include four attributes: content, padding, border, and margin, but the content part of the IE box model includes padding and border. Generally, in order to be compatible with multiple browsers, we use the standard box model and only need to add the DOCTYPE declaration.

1), abbreviation of attribute value

①If two attribute values ​​are given, the former represents the upper and lower attributes, and the latter represents the left and right attributes. ②If three attribute values ​​are given, the former represents the upper attribute, the middle value represents the left and right attributes, and the latter represents the lower attribute. ③If four attribute values ​​are given, it means the attributes of top, right, bottom, and left. That is, sort clockwise.

2) Standard flow: Standard flow can be understood as the arrangement of tags. Designing the arrangement of tags produces block-level elements and inline elements.

3). Classification of elements:

①Block-level elements: Each block-level element occupies one line of height by default. Representation method

.

②Inline elements: Compared with block-level elements, inline elements can be understood as one line can accommodate multiple elements. The representation is .

4. What is the use of the box model?

The box model in CSS is to allow us to fully understand the positioning function of the p+css model. It uses the layout method of the box model to replace the traditional

table

layout method. Therefore, the box model is a model that must be learned when learning the p+css layout method. Through this model, we can understand how the relative positions between p and p in the web page are laid out.

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