媒體查詢—-變色測試
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
.a{
border: 1px solid #000000;
width: 100px;
height: 100px;
background-color: #000000;
}
@media only screen and (min-width: 300px) and (max-width: 640px) {
.a{
background-color: red;
}
}
@media only screen and (min-width: 700px) {
.a{
background-color: green;
}
}
@media only screen and (max-width:200px ) {
.a{
background-color: blue;
}
}
</style>
</head>
<body>
<div class="a"></div>
</body>
</html>