body {
  background-image: url(../images/1bgarab4u.jpg);
  background-repeat: no-repeat;
  background-attachment: fixed;  
  background-size: cover;
  font-family:Roboto, Geneva, sans-serif;
  font-size:18px;
  margin: auto;
 }

@media (max-width: 700px) 
{
   body
   {
       font-size: 15px; 
   }
}

@media (min-width: 900px) 
{
   body
   {
       font-size: 30px; 
   }
}

/* Make content area fill the entire browser window */
html,
.fullscreen {
  display:block;
  height: 100%;
  width: 100%;
}


/* Center the content in the browser window */
main {
max-width: 900px;
 margin: auto;
  }

.center {
 display: block;
 position: relative;
}

.wrapper {
  position: relative;
  padding: 0 10px 20px 10px;
  text-align: center;
}

.buttonback {
  position: fixed;
  z-index: 99;
  right: 0;  
  width: 200px;
  height: auto;
  bottom: 0.5rem;
} 

.imgbuttonback {
  width: 100%;
  height: auto;
}

#content-desktop {display: block;}
#content-mobile {display: none;}

@media screen and (max-width: 768px) {

#content-desktop {display: none;}
#content-mobile {display: block;}

}