Organizzare div al'interno di un altro div

[chigibi]

div#box1{float: left;
width: 100%;
height: 200px;
background-color: #fff;
text-align:center;
padding: 1em 0 0 10px}


div#box2{float: left;
width: 100%;
height: 30px;
text-align:center;
background-color: #fff;
padding: 1em 0 0 10px}


div#box3{float: left;
width: 100%;
height: 40px;
background-color: #fff;
text-align:center;
padding: 1em 0 0 10px}


div#box4{float: left;
width: 90%;
align:center;
background-color: #fff;
border-width: thin;
border-color: #ccc;
border-style: solid;
padding: 2%;}