.hide {
   display: none;
}

.center {
   position: absolute;
   top: 50%;
   left: 50%;
   width: 100px;
   height: 100px;
   margin-top: -50px;
   margin-left: -50px;
}

.print-frame {
   display: none;
}

#hidden-print {
   position: absolute;
   top: 0;
   left: 0;
   z-index: -1;
   visibility: hidden;
   width: 50%;
   font-size: medium;
}

#hidden-print h1, #hidden-print h2, #hidden-print h3, #hidden-print h4, #hidden-print h5, #hidden-print h6 {
  margin-bottom: 2rem;
}