What are the layout methods of css?

css layout method: 1. Single-column layout, including single-column layout with equal width of header, content, and footer, and single-column layout with header and footer filling the screen width and slightly narrower content; 2. Two-column adaptive layout; 3. Three-column layout, including Holy Grail layout and double-wing layout.

The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.

1. Single-column layout

There are two common single-column layouts:

Single-column layout with equal widths for header, content, and footer

Implementation:
Use width or max-width to set the same width for header, content, and footer width (when the screen is smaller than the set width, the former will have a scroll bar, and the latter will display the actual width of the screen), and then use margin:0 auto; to achieve horizontal centering.
html part:

css part:

Header and footer occupy the screen width, and the content is slightly narrower single-column layout

Implementation:

Do not set the width of header and footer. Block-level elements will fill the screen width. Use width or max- for content. width sets the same width (the difference is the same as above), and then uses margin:0 auto; to achieve horizontal centering.

html part is the same as above

css part:

2. Two-column adaptive layout

Two-column adaptive layout refers to a layout method in which one column is stretched by the width of the content, and the remaining column fills the remaining width of the screen.

Use float overflow:hidden to achieve
The adaptive two-column layout mainly triggers BFC (formatting context, yes) through overflow:hidden The CSS rendering mode of the box model layout in the web page refers to an independent rendering area or an isolated independent container.) to implement, one of the characteristics of BFC is not overlapping floating elements.
html part:

css part:

Use flex layout to achieve
Flex layout is also called flexible box layout , which can easily implement the layout method. The disadvantage is that it is not compatible with IE10 or below.
The html part is the same as above.
css part:

Flex is flex-grow (defining the method proportion of the item), flex-shrink (defining the abbreviation proportion of the item), flex-basis (defining the method of allocating excess space before , the abbreviation of the main axis space occupied by the project), flex:1 is equivalent to flex-grow:1;flex-shrink:1;flex-basis:0;

Use grid layout to implement
Grid layout is a two-dimensional grid-based layout system used to optimize user interface design.
The html part is the same as above.
css part:

Three-column layout

Three-column layout It refers to the fixed width of the columns on both sides and the adaptive width of the middle column. This article mainly introduces the Holy Grail layout and the double flying wing layout.

Holy Grail Layout

Features: The DOM structure must first write the middle column part, so that the middle column can be loaded first.

html part:

css implementation steps:

1. Set all three column parts to left floating, Set the width of the middle column to 100% to achieve middle adaptation. At this time, left and right will be squeezed to the next row.

2. Set the value of margin-left to a negative value for both left and right, so that left and right can be returned to the same line as center.

3. Set the padding-left and padding-right of the parent element container to make space for the left column part and the right column part.

4. Set the left column part and the right column part to relative positioning, and set their left and right attributes.

Complete css code:

Disadvantages
There is a minimum width. When the page is smaller than the minimum width, the layout will be messed up. So it's best to set a min-width for the body. This min-width definitely cannot be determined by testing. How to calculate it? It is left-width * 2 right-width. As for why, simply put: "Because relative positioning is set, when the original position of left overlaps the position of right, a line will wrap if it cannot fit due to floating." . So the layout is disrupted. This problem can be avoided by using a double flying wing layout.

Double Flying Wing Layout
It is similar to the Holy Grail layout, but the Double Flying Wing layout changes the DOM document structure.
html part:

css implementation steps:
1. Set the float of left, right, and center to left, and then set the width of center to 100% .
2. Set the margin-left of left to -100%, and set the margin-left of right to the negative value of its width.
3. Set the margin attribute value of inner in center.
Complete css code:

Effect:

##Comparison of two three-column layouts: 1. Both layouts put the mainstream documents at the front, so that the main column is loaded first.
2. The double-wing layout has one less relative positioning than the Holy Grail layout, and the css structure is simpler. But the Holy Grail's html layout may be even more clear in one step.
3. Both layouts have a fixed width on the left and a right, and an adaptive layout structure in the middle width. They both use negative margin-left values ​​for positioning.

Programming Video! !

The above is the detailed content of What are the layout methods of css?. For more information, please follow other related articles on the PHP Chinese website!