css片自适应大小,css片自适应拉伸

自适应屏幕大小，撑满全屏（图片宽高比会随屏幕宽高比变化）不随着滚动条滚动 .bg{ background: url("~@/assets/images/主背景.png"); position:fixed; top: 0; left: 0; width:100%; height:100%; min-width: 1000px; z-index:-10; zoom: 1; background-color: #fff; background-repeat: no-repeat; background-size: cover; -webkit-background-size: cover; -o-background-size: cover; background-position: center 0;}