Detailed introduction to the importance of !important in CSS

!important in CSS is a very important attribute and sometimes plays a very important role. 52CSS.com does not have much knowledge in this area. Let’s read the following article to get a comparative understanding of it. .
When I was writing some CSS code a few days ago, it was difficult for me again, because the damn IE6’s support for CSS is so poor. I haven’t noticed it before, because the things I make are basically based on IE, but The CSS I wrote for my blog this time needs to support more than one browser: IE. The unfortunate thing is that I installed Windows 7, which comes with the IE8 browser. I thought there was no problem, but when I opened IE6, misalignment still occurred. , so I decided to see what was going on with IE6.
I wrapped all CSS blocks with borders, and found that the distance between two p’s in IE is obviously wider than in other browsers. For example, if you write a p with a margin attribute of 20px, then in IE It seems to be 40px in IE, which is why the accuracy calculation is just right, but it is misaligned in IE.
Later I saw the !important attribute. This attribute is actually included in the CSS specification. As a result, IE6 does not support it. It is precisely because it does not support that many CSSers have found a solution. Generally speaking, in CSS, if you write two same attributes in the same CSS block, then the bottom one is actually executed, for example:

   1: home{
   2:    margin-left:20px;
   3:    margin-left:40px;
   4: }
   5:

Then when executing is actually executed according to 40px. The appearance of !important is to allow users to set the priority of the executed statement. If you change the above statement to:

 1: home{
   2:    margin-left:20px!important;
   3:    margin-left:40px;
   4: }
   5:

Then it will be executed as 20px under Firefox, Google Chrome and IE7 or above, but it will still be executed as 40px under IE6, because IE6 does not support the !important specification. We can follow this rule to meet the design needs of IE6. When we find that the display effects of IE6 and other browsers are different, then set two, add the !important tag to the upper one, and the lower one There is no need to add a sentence, so IE6 will execute it as follows. A senior CSSer said: Today’s CSS is everywhere! Important. This is all the fault of damn IE6. It is no exaggeration to say that IE6 is just a pile of metabolites.

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