body.function-login {
height:100%;
background:transparent url("https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjh5Vd5h4QrdK_0kJqLa05B6crVMiX1rxvNDGDLr_w6FWS3j4nGxyog5eB0Jqs2QVKpt1X2r_JF3qzg7RBoJu2LPkpmES_lah1hnRy37C04iNCwoJ2fuStb-WkzJKxDNlppBo-Uu3XJBQfe4bauuzKARVEUzV4T73KWD0C9y5CkElRQdU3TAjH9yyALUa8/w640-h480/desktop2.jpeg") no-repeat center center fixed;
background-size:cover;
}