header{
  height: 91px;
}
/* Next & previous buttons */
#prev, #next {
    cursor: pointer;
    position: absolute;
    top: 50%;
    width: auto;
    margin-top: -22px;
    padding: 16px;
    color: white;
    font-weight: bold;
    font-size: 18px;
    transition: 0.6s ease;
    border-radius: 0 3px 3px 0;
    user-select: none;
  }
  
  /* Position the "next button" to the right */
  #next {    
    right: 0;
    border-radius: 3px 0 0 3px;
  }
  
  /* On hover, add a black background color with a little bit see-through */
  #prev:hover, .next:hover {
    background-color: rgba(0,0,0,0.8);
  }
  
  
#proyectos{
  outline-color: transparent;
}
  @media screen and (orientation:portrait ){
    #prev, #next {
      opacity:0;      
      cursor: none;
      top: 0%;
      height: 550px;
      width: 100px;
      outline-color: transparent;        
    }
   
}