html,
body {
  height: 100vh;
  width: 100vw;
}

body {
  overflow: hidden;
  background-color: slategrey;
}

.right {
  height: 100%;
  margin: 0;
  width: 75vw;
  float: right;
  background-color: navy;
}

.left {
  background-color: blueviolet;
  height: 100%;
  float: left;
}

span {
  color: lightgray;
  font-family: Arial, Helvetica, sans-serif;
}

.fullsize {
  height: 100%;
  margin: 0;
}

.buttons {
  display: flex;
  justify-content: space-between;
}

.main {
  height: 100vh;
  width: 100vw;
  position: absolute;
  top: 0;
  left: 0;
}

#cnvdiv {
  position: relative;
  height: 100%;
  width: 100%;
  /*display: flex;*/
  /*text-align: center;*/
  /*justify-content: center;*/
}

.stack {
  position: relative;
  height: 100%;
  /*text-align: center;*/
  /*float: right;*/
  /*margin-right: 0;*/
  /*margin-left: auto;*/
  /*display: block;*/
}

.stack>canvas {
  position: absolute;
  /*display: block;*/
  /*display: inline;*/
  left: 0;
  top: 0;
}