/* IE 6 fix */
* html .twit-post .delete_note a { background-position-y: 2px; }
* html .twit-post .delete_note a:hover { background-position-y: -14px; }

注意接受的答案也是针对IE10。因此，为了更完整的列表：

IE 6

* html .ie6 {property:value;}

要么

.ie6 { _property:value;}

IE 7

*+html .ie7 {property:value;}

要么

*:first-child+html .ie7 {property:value;}

IE 6和7

@media screen\9 {
    .ie67 {property:value;}
}

要么

.ie67 { *property:value;}

要么

.ie67 { #property:value;}

IE 6,7和8

@media \0screen\,screen\9 {
    .ie678 {property:value;}
}

IE 8

html>/**/body .ie8 {property:value;}

要么

@media \0screen {
    .ie8 {property:value;}
}

IE 8标准模式

.ie8 { property /*\**/: value\9 }

IE 8,9和10

@media screen\0 {
    .ie8910 {property:value;}
}

仅IE 9

@media screen and (min-width:0) and (min-resolution: .001dpcm) { 
 // IE9 CSS
 .ie9{property:value;}
}

IE 9及以上

@media screen and (min-width:0) and (min-resolution: +72dpi) {
  // IE9+ CSS
  .ie9up{property:value;}
}

IE 9和10

@media screen and (min-width:0) {
    .ie910{property:value;}
}

仅IE 10

_:-ms-lang(x),.ie10 { property:value\9; }

IE 10及以上

_:-ms-lang(x),.ie10up { property:value; }

要么

@media all and (-ms-high-contrast: none),(-ms-high-contrast: active) {
   .ie10up{property:value;}
}

IE 11(及以上..)

_:-ms-fullscreen,:root .ie11up { property:value; }

Javascript替代品

Modernizr

Modernizr runs quickly on page load to detect features; it then
creates a JavaScript object with the results,and adds classes to the
html element

User agent selection

Javascript：

var b = document.documentElement;
        b.setAttribute('data-useragent',navigator.userAgent);
        b.setAttribute('data-platform',navigator.platform );
        b.className += ((!!('ontouchstart' in window) || !!('onmsgesturechange' in window))?' touch':'');

添加(例如)以下到html元素：

data-useragent='Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C)'
data-platform='Win32'

允许非常有针对性的CSS选择器，例如：

html[data-useragent*='Chrome/13.0'] .nav{
    background:url(img/radial_grad.png) center bottom no-repeat;
}

脚注

如有可能，请避免浏览器定位。识别并修复您识别的任何问题。支持progressive enhancement和graceful degradation.考虑到这一点，这是一个“理想的世界”场景，在生产环境中并不总是可以实现的，因此上述方法应该有助于提供一些好的选择。

归因/基本阅读

> Keith Clarke
> Paul Irish
> Web Devout
> The Spanner