html, body {
            margin: 0;
            padding: 0;
            width: 100%;
            height: 100%;
            background-color: #fff;
            font-family:'Roboto', sans-serif;
            line-height: 1.4;
            }
h1{
            margin-left: 1em;
            }

a:link, a:visited  {
            color: black;
            background-color: transparent;
            text-decoration: none;
          }

.viewer {
            width: 100vw;
            height: 100vh;
            border: none;
            display: block;
        }
.hidden {
            display: none;
        }
        
main {
            flex: 1;
}

#controls {
            position: fixed;
            top: 10px;
            right: 10px;
            background: rgba(0,0,0,0.4);
            color: #fff;
            padding: 0.5rem 1rem;
            border-radius: 4px;
            font-size: 0.9rem;
            cursor: pointer;
            z-index: 10;
        }
#about {
        width: 50%;
        margin-left: 6em;
        padding: 2em;
        }
        
#footer {
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      text-align: center;
      padding: 0.5rem 0;
      background: transparent;
      color: #666;
      font-size: 0.8rem;
        }