.header {
  width: 100%;
  height: 150px;
  background: url(https://www.lecbasvepomoci.cz/wp-content/themes/lecbasvepomoci/less/images/logo.png) top center no-repeat;
  background-color: white;
  background-size: 710px;
  position: fixed;
  font-weight: bolder;
  display: block;
  -webkit-box-shadow: 0px 3px 33px 9px #ffffff;
  -moz-box-shadow: 0px 3px 33px 9px #ffffff;
  box-shadow: 0px 3px 33px 9px #ffffff;
}