.box
{
margin:auto;
margin-top:10px;
background-color:red;
border: solid black;
height:250px;
width:300px;

}

.box1
{
margin:auto;
margin-top:15px;
background-color:green;
border: solid black;
height:200px;
width:90%;

}

.box2
{
margin:auto;
margin-top:20px;
background-color:blue;
border: solid black;
height:150px;
width:80%;

}

.box3
{
margin:auto;
margin-top:25px;
background-color:pink;
border: solid black;
height:100px;
width:70%;

}