CSS Multi-Browsing FAQs Detailed Introduction

It's a cliché that CSS is compatible with every browser, and the tutorials on the web are everywhere.
The following content is not too many novel, purely personal summary, hoping to have some help for beginners.
First, CSS HACK
The following two methods can solve almost all of today's hack.

1,!important

With IE7 support for!important, the!important method is now only for IE6 hack.
(Note the wording. Remember that the statement location needs to be advanced.)
<style>
#wrapper
{
Width:100px!important; /* IE7+FF */
width:80px; /* IE6 */
}
</style>

2, Ie6/ie77 to Firefox

*+html and *html is the unique label of IE, Firefox is not supported. And *+html is a special label for IE7.
<style>
#wrapper
{
#wrapper {width:120px;}/* FireFox */
*html #wrapper {width:80px;}/* IE6 fixed */
*+html #wrapper {width:60px;}/* IE7 fixed, note order */
}
</style>

Attention:
*+html to IE7 hack must ensure that the HTML top has the following declaration:
<! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" "HTTP://WWW.W3.ORG/TR/HTML4/LOOSE.DTD" >
Second, Universal float closed

The principle of clear float can be found in [how to clear floats without Structural Markup]
Add the following code to the global CSS, to the need to close the P plus class= "Clearfix" can be done.
<style>
/* Clear Fix */

. clearfix:after
{
Content: ".";
Display:block;
height:0;
Clear:both;
Visibility:hidden;
}
. clearfix
{
Display:inline-block;
}
/* Hide from IE MAC */
. clearfix {Display:block;}
/* End Hide from IE Mac */
/* End of Clearfix */
</style>
Third, other compatibility skills

1, FF setting padding after p will cause width and height to increase, but IE will not. (Can be resolved with!important)
2, centering problem.
1). Center vertically. Set the line-height to the same height as the current p, and then through the vertical-align:middle. (Note that the content does not wrap.)
2). Center horizontally. margin:0 Auto; (of course not everything)
3, if you need to give the contents of a tag style, you need to set display:block; (common in navigation labels)
4, FF and IE to the BOX understanding of the difference caused by 2px is also set to float p in IE margin doubled and so on.
5, UL label under FF The default is List-style and padding. It is advisable to declare beforehand to avoid unnecessary trouble. (Common in navigation labels and table of contents)
6, as the external wrapper p do not set dead height, preferably plus overflow:hidden. To achieve a high degree of self-adaptation.
7, about the hand-shaped cursor. Cursor:pointer. And hand only applies to IE.

1 CSS styles for Firefox IE6 IE7
Most are now using!important to hack, for IE6 and Firefox test can display normally,
But IE7 to!important can be correctly explained, will cause the page did not display as required! Find a needle
IE7 good hack Way is to use "*+html", now with IE7 browsing, there should be no problem.
Now write a CSS that can do this:

#1 {color: #333;}/* Moz */
* HTML #1 {color: #666;}/* IE6 */
*+html #1 {color: #999;}/* IE7 */
Then under Firefox font color display as #333,ie6 under the font color display as #666,ie7 under the font color display as #999.

2 centering issues in CSS layouts
The main style definitions are as follows:

body {text-align:center;}
#center {Margin-right:auto; Margin-left:auto; }
Description
The text-align:center is defined first in the parent element, which means that the content within the parent element is centered, and the setting for IE is already available.
But it can't be centered in Mozilla. The solution is to add "Margin-right:auto" when the child element is defined; Margin-left:auto; ”
It is necessary to note that if you want to use this method to center the entire page, it is recommended not to put in a p, you can sequentially split the number of P,
As long as the margin-right:auto is defined in each of the removed P; Margin-left:auto; You can do it.

3 box models different interpretations

#box {width:600px;//for ie6.0-w\idth:500px;//for ff+ie6.0}
#box {width:600px!important//for ff width:600px;//for ff+ie6.0 width/**/:500px;//for ie6.0-}

4 The double distance generated by the floating IE

#box {float:left; width:100px; margin:0 0 0 100px; In this case, IE will produce 200px distance display:inline; Make floating Ignore}
Here Block,inline two elements, the block element is characterized by: always start on the new line, height, width, row height, the margin can be controlled (block elements), the characteristics of the inline element is: and other elements on the same line,... Uncontrollable (inline element);

#box {display:block;//can simulate a block element display:inline for inline elements;//Achieve the effect of the same row arrangement diplay:table;

IE does not recognize the definition of min-, but in fact it treats the normal width and height as a condition of min. This is a big problem, if you only use width and height,
In the normal browser these two values will not change, if only with min-width and min-height words, ie below is basically not set width and height.
For example, to set the background image, this width is more important. To solve this problem, you can:
#box {width:80px; height:35px;} Html>body #box {width:auto; height:auto; min-width:80px; min-height:35px;}

6 minimum width of the page

Min-width is a handy CSS command that allows you to specify that the element should be minimal or less than a certain width, so that the layout is always correct. But IE does not recognize this,
And it actually puts width as the minimum width. To make this command available on IE, you can put a <p> into the <body> tab and specify a class for P:
Then the CSS is designed like this:
#container {min-width:600px; Width:expression (Document.body.clientWidth < 600?) "600px": "Auto");}
The first min-width is normal, but the width of line 2nd uses JavaScript, which only IE recognizes, which also makes your HTML document less formal. It actually achieves the minimum width by JavaScript's judgment.

7 Clear Float

. hackbox{display:table;//Display the object as a block-element-level table} or. hackbox{Clear:both;}
or join: After (pseudo-object), set what happens after the object, usually in conjunction with content, IE does not support this pseudo-object, non-IE browser support,
So it doesn't affect the Ie/win browser. This is the most troublesome of ... #box: after{content: "."; display:block; height:0; clear:both; visibility:hidden;}

8 p floating IE text generates 3 pixel bug

The left object floats, the right side is positioned with the left margin of the outer patch, and the text within the right object is spaced 3px away from the left.

#box {float:left; width:800px;} #left {float:left; width:50%;} #right {width:50%;} *html #left {margin-right:-3px;//This sentence is the key}
HTML code <p id= "box" > <p id= "left" ></p> <p id= ' right ' ></p></p>

9 attribute Selector (this is not compatible, is a bug to hide CSS)

p[id]{}p[id]{}
This is hidden for IE6.0 and IE6.0 versions, and the FF and opera functions
There is a difference between the property selector and the child selector, the range of the child selector is reduced in form, the range of the property selector is larger, such as P[id], and all P tags have the same type of ID.

Ten IE hide and seek problems

When P is applied complex, there are some links in each column, and P and so on are prone to hide and seek.
Some content does not show up when the mouse selects this area is found content is indeed on the page.
WORKAROUND: Use Line-height attribute for #layout or use fixed height and width for #layout. The page structure is as simple as possible.

11 Height not adapted

Height is not adjusted when the height of the inner object changes, the outer height cannot be automatically adjusted, especially when the inner layer object uses
Margin or paddign.
Cases:
<p id= "box" >
Content in the <p>p object </p>
</p>
CSS: #box {background-color: #eee;}
#box p {margin-top:20px;margin-bottom:20px; text-align:center;}
Workaround: Add 2 empty P-Object CSS code to the P object:. 1{height:0px;overflow:hidden;} Or add the Border property to P.

Vi. CSS Compatibility essentials analysis IE vs FF

CSS Compatibility essentials:

DOCTYPE affecting CSS Processing

Ff:p set Margin-left, Margin-right is auto when the center, IE No

Ff:body setting text-align, p needs to set Margin:auto (mainly margin-left,margin-right) to center

FF: After setting padding, p will increase height and width, but IE will not, therefore need to set a height and width with!important

FF: Support!important, IE is ignored, can be used!important to set the FF special style

Vertical centering Problem of P: vertical-align:middle; Increase the line spacing to as high as the whole P line-height:200px; Then insert the text and center it vertically. The disadvantage is to control the content not to break the line

Cursor:pointer can display the cursor finger in IE FF at the same time, hand only IE can

FF: Link plus border and background color, need to set Display:block, and set Float:left guarantee not to break line. Refer to MenuBar, set a and menubar height is to avoid the bottom of the display dislocation, if not set height, you can insert a space in the MenuBar xhtml+css compatibility solution small Set

The use of XHTML+CSS framework benefits a lot, but there are some problems, whether because of the use of unskilled or the idea is not clear, I first put some of the problems I encountered in the following, the province of everyone looking around ^ ^

1, in Mozilla Firefox and IE in the box model interpretation inconsistent lead to 2px resolution method:

p{margin:30px!important;margin:28px;}

Note that the order of the two margin must not be written in reverse, according to the statement!important this property IE is not recognized, but other browsers can be recognized. So under IE it is actually interpreted as:

P{MARING:30PX;MARGIN:28PX}

Repeat definition is executed according to the last one, so it is not possible to write only margin:xxpx!important;

2, IE5 and IE6 box interpretation inconsistent IE5 under p{width:300px;margin:0 10px 0 10px;} The width of P is interpreted as 300px-10px (right padding) -10px (left padding) The final p width is 280px, while the width on IE6 and other browsers is calculated as 300px+10px (right padding) +10px (left padding) =320px. At this point we can make the following changes

P{width:300px!important;width/**/:340px;margin:0 10px 0 10px}

, about this/**/is what I also do not understand, only know IE5 and Firefox support but IE6 not support, if anyone understand, please tell me, thank you! ：）

3, the UL tag in Mozilla default is padding value, and in IE only margin has value so define first

ul{margin:0;padding:0;}

Will solve most of the problems.

4, about the script, in xhtml1.1 does not support the language attribute, only need to change the code to

< type= "Text/java" >

You can do it.

Seven, 10 css tricks you don't necessarily know

1. CSS font attributes shorthand rules

The general use of CSS to set font properties is to do this:

Font-weight:bold;

Font-style:italic;

Font-varient:small-caps;

Font-size:1em;

Line-height:1.5em;

Font-family:verdana,sans-serif;

But you can also write them all in one line:

Font:bold Italic small-caps 1em/1.5em Verdana,sans-serif;

That's great! There is only one point to be reminded: this shorthand method only works if you specify both the Font-size and Font-family properties. Also, if you do not set Font-weight, Font-style, and font-varient, they will use the default values, which should be remembered.

2. Use two classes at a time

Typically you can only set a class for one element, but that doesn't mean you can't use two of them. In fact, you can do this:

<p class= "text side" >...</p>

The P element is also given two classes, the middle is opened with an empty space, so that all text and side two class attributes will be added to the P element. If there are conflicting attributes in their two classes, the latter setting works, that is, the properties of the class that are placed in the CSS file are in effect.

Add: For an ID, can't write <p id= "text side" >...</p> can't write like this

3, the default value of CSS border

You can usually set the color, width and style of the boundary, such as:

BORDER:3PX Solid #000

This shows the border as 3 pixels wide, black, solid line. But in fact, you just need to specify the style.

If only the style is specified, the default values are used by the other properties. Generally, the border width defaults to medium, typically 3 to 4 pixels, and the default color is the color of the text in it. If the value is just right, you don't have to set that much.

4. CSS for document printing

Many web sites have a print-ready version, but this is not really necessary because you can use CSS to set the print style.

That is, you can specify two CSS files for the page, one for the screen display, and one for printing:

<link type= "Text/css" rel= "stylesheet" href= "/blog/stylesheet.css" media= "screen"/> <link type= "Text/css" Rel= "stylesheet" href= "Printstyle.css" media= "print"/>

Line 1th is the display, line 2nd is print, note the media properties.

But what should I write in the printed CSS? You can set it up by designing a common CSS method. At the same time, the CSS can be set to display CSS to check its effect. Perhaps you will use the Display:none command to turn off some decorative pictures, and then turn off some of the navigation buttons. To learn more, you can look at the "Print differences" article.

5, Picture replacement skills

It is generally recommended that you display text in standard HTML instead of using a picture, which is faster and more readable. But if you want to use some special fonts, you can only use pictures.

For example, you want the entire sale of the icon, you use this picture:

Of course, but for search engines, compared to normal text, they have little interest in alt text, because many designers here put a lot of keywords to cheat search engines. So the method should be this:

But then there is no special font. To achieve the same effect, you can design css like this:

H1 {Background:url (/blog/widget-image.gif) no-repeat; height:image height text-indent: -2000px}

Be careful to change the image height to the true picture. Here, the picture will be shown as the background, and the real text because of the set-2000 pixels of this indentation, they will appear on the left side of the screen 2000 points, it is not visible. But this is for the person who closes the picture, may not see all, this should pay attention to.

6. Another adjustment technique for CSS box model

The box model is mostly tuned for IE before IE6, which calculates the width of the boundary and the space between the elements. Like what:

#box {width:100px; border:5px; padding:20px}

Call it this way:

<p id= "box" >...</p>

At this point the full width of the box should be 150 points, which is correct on all browsers except for the IE browser before IE6. But on a browser like IE5, its full width is still 100 points. This difference can be handled using the box adjustment method previously invented by people.

But using CSS can also achieve the same goal, so that they show the same effect.

#box {width:150px} #box p {border:5px; padding:20px}

This is called:

<p id= "box" ><p>...</p></p>

In this way, no matter what browser, the width is 150 points.

7, block Element Center alignment

If you want to make a fixed-width page and want the page to be centered horizontally, this is usually the case:

#content {width:700px; margin:0 auto}

You will use <p id= "content" > to surround all the elements. This is simple, but not good enough, IE6 the previous version will not show this effect. Change the CSS as follows:

Body {Text-align:center} #content {text-align:left; width:700px; margin:0 Auto}

This will center the contents of the page, so in the content is added

Text-align:left.

8. Use CSS to handle vertical alignment

The Vertical alignment table can be easily implemented, and the table cell Vertical-align:middle can be set. But it doesn't work for CSS. Setting this property is useless if you want to set a navigation bar that is 2em high and you want the navigation text to be centered vertically.

What is a CSS method? By the 2EM:LINE-HEIGHT:2EM, you can set the line height of these words to be the same.

9, CSS positioning within the container

One of the benefits of CSS is that you can position an element arbitrarily, within a container. For example, for this container:

#container {position:relative}

This allows all elements in the container to be positioned relative to each other so that they can be used:

<p id= "container" ><p id= "navigation" >...</p></p>

If you want to position to the left 30 points, 5 points above, you can:

#navigation {position:absolute; left:30px; top:5px}

Of course, you can also:

margin:5px 0 0 30px

Note that the order of 4 numbers is: top, right, bottom, left. Of course, it is sometimes better to locate the method rather than the margin.

10, straight to the bottom of the screen background color

In the vertical direction is the control is not the CSS. If you want the navigation bar and the content bar to pass directly to the bottom of the page, it is convenient to use the table, but if you only use CSS like this:

#navigation {background:blue; width:150px}

A shorter navigation bar won't pass through to the bottom, and it will end when the content ends. What should we do?

Unfortunately, you can only use deception, give the shorter column a background, width and column width, and let its color and set the background color.

Body {background:url (/blog/blue-image.gif) 0 0 Repeat-y}

Do not use EM at this time, because then, once the reader changes the font size, the trick will be revealed, only use PX.