body{
    margin-left: auto; 
    margin-right: auto;
    width:800px;
    max-width: 90%;

}

@media (min-width: 640px) {
    html {background-color: #eaf6ff; }
  }

@media (max-width: 500px) {
    h1 {font-size: 1.5rem; }
  }

  @media (min-width: 640px) {
    h1 {font-size: 2.5rem; }
  }

#fixed-size-grid-items li {
	width: 170px;
	margin: 10px;
	font-size: 0.8rem;
    display: inline-block;
    list-style: none;
	vertical-align: top;
}

#fixed-size-grid-items ul{
	padding-left: 0px;
}

#stretchable-grid-items ul{
	width: 100%;
	padding-left: 0px;
	display: flex;
    flex-wrap: wrap;
    vertical-align: top;
	font-size: 0.8rem;
	list-style: none;
}

@media (min-width: 480px) {
    #stretchable-grid-items li {
        width: 50%; 
   }
}

@media (min-width: 640px) {
    #stretchable-grid-items li {
        width: 25%; 
   }
}
	
#stretchable-grid-items ul {
    padding-left: 0px;
	width: 100%;
    margin-left: -10px;
	margin-right: -10px;
	margin-top: 1rem;
	margin-bottom: 1rem;
}

#stretchable-grid-items ul li aside {
	margin: 10px;
}