.site-header{
  transition: background 0.1s;
}
@media(min-width:34em){
  .site-header {background: url(http://car-evolution.de/wp-content/uploads/2016/04/flowRoot3336.png) no-repeat 1% 82%;}
}
@media(min-width:48em){
    .site-header {background: url(http://car-evolution.de/wp-content/uploads/2016/08/g4481_2.png) no-repeat 20vw -10em, url(http://car-evolution.de/wp-content/uploads/2016/04/flowRoot3336.png) no-repeat 1% 82%;}
}
@media(min-width:62em){
    .site-header {background: url(http://car-evolution.de/wp-content/uploads/2016/08/g4481_2.png) no-repeat  30vw -10em, url(http://car-evolution.de/wp-content/uploads/2016/04/flowRoot3336.png) no-repeat 1% 82%;}
}
@media(min-width:75em){
    .site-header {background: url(http://car-evolution.de/wp-content/uploads/2016/08/g4481_2.png) no-repeat 40vw -10em, url(http://car-evolution.de/wp-content/uploads/2016/04/flowRoot3336.png) no-repeat 1% 82%;}
}