CSS实现背景透明完美解决方案

.alp60 {
  background: rgb(255, 255, 255);
  background: rgba(255, 255, 255, 0.6);
  background: transparent\9;
  zoom: 1;
  filter:progid:DXImageTransform.Microsoft.gradient(startColorstr=#99ffffff, endColorstr=#99ffffff);
  -ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#99ffffff, endColorstr=#99ffffff)";
}

转自：http://robertnyman.com/2010/01/11/css-background-transparency-without-affecting-child-elements-through-rgba-and-filters/