CSS学习（十五）-CSS颜色模式、CSS颜色透明度_html/css_WEB-ITnose

一、理论：
1.CSS3颜色模式
a.RGBA颜色模式，在RGB基础上加了控制alpha透明度的参数
b.HSL颜色模式：色调 饱和度 亮度
c.HSLA颜色模式：A值取于0-1之间，值越大，透明度越低
2.RGBA/HSLA滤镜格式
a.需要用转换工具才能在ie8及以下版本中使用RGBA/HSLA颜色模式相同的透明度，需要将RGBA/HSLA中的透明值乘以255，然后将其转换成十六进制值

二、实践：

1.

    <meta charset="UTF-8">    <title>Title</title>    <style type="text/css">        .row{            overflow: hidden;        }        .row div{            width: 80px;            height: 80px;            line-height: 80px;            text-align: center;            float:left;        }        .row:nth-of-type(1) div {            background: rgba(135,162,31,0.8);        }        .row:nth-of-type(2) div {            background: rgba(135,162,31,0.6);        }        .row:nth-of-type(3) div {            background: rgba(135,162,31,0.4);        }        .row:nth-of-type(4) div{            background: rgba(135,162,31,0.2);        }        .row div:nth-child(1){            background: rgba(135,162,31,0.8);        }        .row div:nth-child(2){            background: rgba(135,162,31,0.7);        }        .row div:nth-child(3){            background: rgba(135,162,31,0.6);        }        .row div:nth-child(4){            background: rgba(135,162,31,0.5);        }        .row div:nth-child(5){            background: rgba(135,162,31,0.4);        }        .row div:nth-child(6){            background: rgba(135,162,31,0.3);        }        .row div:nth-of-type(1) div {            background: rgba(135,162,31,0.2);        }    </style><div class="demo">    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>
</div>

2.

    <meta charset="UTF-8">    <title>Title</title>    <style type="text/css">        .row{            overflow: hidden;        }        .row div{            width: 80px;            height: 80px;            line-height: 80px;            text-align: center;            float:left;        }        .row:nth-of-type(1) div {            background: hsl(133,100%,80%);        }        .row:nth-of-type(2) div {            background: hsl(133,80%,80%);        }        .row:nth-of-type(3) div {            background:  hsl(133,60%,80%);        }        .row:nth-of-type(4) div{            background: hsl(133,50%,80%);        }        .row div:nth-child(1){            background: hsl(33,100%,70%);        }        .row div:nth-child(2){            background: hsl(33,90%,70%);        }        .row div:nth-child(3){            background: hsl(33,80%,70%);        }        .row div:nth-child(4){            background: hsl(33,70%,70%);        }        .row div:nth-child(5){            background: hsl(33,60%,70%);        }        .row div:nth-child(6){            background: hsl(33,50%,70%);        }        .row div:nth-of-type(1) div {            background: hsl(33,100%,70%);        }    </style><div class="demo">    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>    <div class="row">        <div>            1        </div>        <div>            0.8        </div>        <div>            0.6        </div>        <div>            0.4        </div>        <div>            0.2        </div>    </div>
</div>