一、理论：
1.RGB色彩模式
a.CMYK色彩模式
b.索引色彩模式 (主要用于web)
c.灰度模式
d.双色调模式
2.opacity:
a.alphavalue:透明度
b.inherit:继承父元素的不透明性
二、实践：
1.RGB色彩模式
a.CMYK色彩模式
b.索引色彩模式 (主要用于web)
c.灰度模式
d.双色调模式
2.opacity:
a.alphavalue:透明度
b.inherit:继承父元素的不透明性
二、实践：
1.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style type="text/css">
.row{
overflow: hidden;
}
.row div{
80px;
height: 80px;
line-height: 80px;
text-align: center;
float:left;
}
.row:nth-of-type(1) div {
background: #202189;
color:#fff;
}
.row:nth-of-type(2) div {
background: #31b231;
}
.row:nth-of-type(3) div {
background: #239587;
}
.row:nth-of-type(4) div{
background: #333333;
}
.row div:nth-child(1){
background: #004099;
color:#8f8f8f;
}
.row div:nth-child(2){
opacity: 1;
}
.row div:nth-child(3){
opacity: 0.8;
}
.row div:nth-child(4){
opacity: 0.6;
}
.row div:nth-child(5){
opacity: 0.4;
}
.row div:nth-child(6){
opacity: 0.2;
}
.row div:nth-of-type(1) div {
opacity: 1;
}
</style>
</head>
<body>
<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>
</body>
</html>