aec-tech-presentation/WebStarter/styles.css

body {
  margin: 0;
  padding: 0;
}

#viewerParent {
  min-width: 100vw;
  min-height: 100vh;
}

#viewer {
  min-width: 100vw;
  min-height: 80vh;
  border: 1px solid black;
}