CSS与JS

*{
box-sizing: border-box;
margin: 0;
padding: 0;
}
a {
display: block;
height: 100px;
width: 200px;
}
div {
display:inline-block;
height: 100px;
width: 200px;
}
.a{
float: right;
}
border: 1px solid red;
position: relative;相对定位
position: absolute;绝对定位
position: fixed;固定定位
.div02{
background-color: silver;
position: absolute;
left: 25px;
z-index: -1;
}
prompt("sad");
alert("点我");

document.getElementById("one").style.backgroundColor="red";
document.getElementById("one").style.height="100px";
document.getElementById("one").style.width="200px";