Css：Condtional comments（条件コメント）
http://msdn.microsoft.com/en-us/library/ms537512(VVS.85).aspx
http://www.quirksmode.org/css/condcom.html
Item Example コメント [if！IE] The NOT operator.This is placed immediatery in front of the feature、operator、or subexpression to reverse the Boolean meaning of the expression.lt [if lt IE 5.5] The less-than operator.Returns true if the first argment is less than the second argment.lte [if lte IE 6] The less-than or equal operator.Returns true if the first argment is less than or equal to the second argt.gt [if gt IE 5] The greater-than operator.Returns true if the first argment is greater than the second argte.gte [if gte IE 7] The greater-than or equal operator.Returns true if the first argment is greaterthan or equal to the second argment.() [if！(IE 7)] Subexpression operators.Used in conjunction with Boolean operators to create more complex expressions.& [if(gt IE 5)&(lt IE 7)] The AND operator.Returns true if all subexpressions evaluate to true| [if(IE 6)|(IE 7)] The OR operator.Returns true if any of the subexpressions evaluates to true
http://www.quirksmode.org/css/condcom.html
Item Example コメント [if！IE] The NOT operator.This is placed immediatery in front of the feature、operator、or subexpression to reverse the Boolean meaning of the expression.lt [if lt IE 5.5] The less-than operator.Returns true if the first argment is less than the second argment.lte [if lte IE 6] The less-than or equal operator.Returns true if the first argment is less than or equal to the second argt.gt [if gt IE 5] The greater-than operator.Returns true if the first argment is greater than the second argte.gte [if gte IE 7] The greater-than or equal operator.Returns true if the first argment is greaterthan or equal to the second argment.() [if！(IE 7)] Subexpression operators.Used in conjunction with Boolean operators to create more complex expressions.& [if(gt IE 5)&(lt IE 7)] The AND operator.Returns true if all subexpressions evaluate to true| [if(IE 6)|(IE 7)] The OR operator.Returns true if any of the subexpressions evaluates to true
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