java - Vaadin Set Image as background -

i trying implement background image on webpage not work.

here code css:

backgroundimage {  body{        background: url("common/images/blue.jpg");     }  

}

here implementing code:

public class loginview extends verticallayout implements view {              private navigator navigator;               textfield txtusername = new textfield("username: ");              passwordfield txtpassword = new passwordfield("password: ");             image image = null;              jdbcconnectionpool connectionpool;              public loginview() {                 setstylename("backgroundimage");             }     } 

try css (without body selector):

.backgroundimage {       background: url("common/images/blue.jpg") !important; } 

and inspect layout in browser, ensure image path correct.