Adaptive width of left and right columns, fixed width of middle columns, and adaptive width of left and right columns

Adaptive width of left and right columns, fixed width of middle columns, and adaptive width of left and right columns

The width of the left and right columns is adaptive, and the width of the middle column is fixed:
The width of the middle column is fixed, and the adaptive effect of the width of the left and right columns is applied in many web pages. The following describes how to achieve this effect:
The code example is as follows:

<! DOCTYPE html> 
The above code implements the effect. You can adjust the window size for testing. The following describes how to achieve this effect:
I. Implementation principle:
1. Set the outer margin of the left and right columns to-150px, so that the middle column can be set between the left and right columns, with a width of PX.
2. Set the left margin of the Child div in the left and right columns to 150px, so that the content of the left and right columns can be displayed in the "-150px margin area" of non-parent elements.
Based on the above principle, the center is fixed and the width of the left and right columns is adaptive.
Ii. Knowledge POint Description:
1. according to the implementation principle, the value of the left and right margin should be-150px, but the actual value is indeed-151px. This is because IE6 and IE7 are not ideal for processing the percentage of width, therefore, we need to increase the Margin Size by one pixel. Otherwise, a line break may occur.
Original address: http://www.51texiao.cn/div_cssjiaocheng/2015/0501/509.html