怎么在dw中插入图片铺满屏幕不溢出！

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">



妖精的尾巴 .body{ margin:0; padding:0; } /*.back{ width:auto; height:1080px; }*/


background: url( 图片路径 ) no-repeat center/cover;