javascript - different size divs align top left -

css

  #box1, #box2, #box3, #box4, #box5, #box6, #box7, #box8, #box9, #box10, #box11, #box12, #box13, #box14, #box15, #box16, #box17, #box18, #box19, #box20 {     position: relative;     list-style: none;     float: left; clear:left: } #box1 {     width: 60px;     height: 60px;     background: yellow; } #box2 {     width: 80px;     height: 50px;     background: blue; } #box3 {     width: 40px;     height: 60px;     background: red; } #box4 {     width: 200px;     height: 150px;     background: green; } #box5 {     width: 60px;     height: 100px;     background: red; } #box6 {     width: 70px;     height: 30px;     background: blue; } #box7 {     width: 40px;     height: 80px;     background: yellow; } #box8 {     width: 90px;     height: 60px;     background: red; } #box9 {     width: 50px;     height: 80px;     background: blue; } #box10 {     width: 40px;     height: 60px;     background: yellow; } #box11 {     width: 60px;     height: 60px;     background: yellow; } #box12 {     width: 80px;     height: 50px;     background: blue; } #box13 {     width: 40px;     height: 60px;     background: red; } #box14 {     width: 100px;     height: 50px;     background: yellow; } #box15 {     width: 60px;     height: 100px;     background: red; } #box16 {     width: 70px;     height: 30px;     background: blue; } #box17 {     width: 40px;     height: 80px;     background: yellow; } #box18 {     width: 90px;     height: 60px;     background: red; } #box19 {     width: 50px;     height: 80px;     background: blue; } #box20 {     width: 40px;     height: 60px;     background: yellow; } 

i need align multiple divs top left, without spaces between divs. need, 1 div stay exact place, need (like "green" div place center of window). in fiddle, can see p17 , p18 not place other divs. there space on divs. need put these 2 divs space.how can fix without giving margins.

and if add new divs, need automaticaly attach divs other divs, same way in demo, without space. there way this.

check [demo][1]   |__||  ||     ||   | |  ||__||_____||   | |  ||         ||___| |__||_________||___| |  ||      ||      | |__||______||______|  ![drawing][2]  need align divs in above demo, drawing. 

http://jsfiddle.net/ramswarnak/g8dkr/8/

http://i.stack.imgur.com/mbllf.png

please add css :

#box1, #box2, #box3, #box4, #box5, #box6, #box7, #box8, #box9, #box10, #box11, #box12, #box13, #box14, #box15, #box16, #box17, #box18, #box19, #box20 {   margin:0px; padding:0px; float: left; }  ul, li {  margin:0px; padding:0px; list-style:none;}