body {
  background-color: #000000;
  color: #00FF00;
  margin: 0;
}

h1, h2, h3 {
  color: #00FFFF;
}

.very-large {
  font-size: 50px;
}

.container {
  display: flex;
  flex-direction: column;
  height: 100vh;
  width: 100vw;
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

.main, .head {
  padding: 10px
}

.main {
  flex-grow: 1;
}

iframe {
  margin: 0;
  border: 4px solid #0000FF;
  width: 100%;
  height: 100%;
  box-sizing: border-box;
}

.cyan {
  color: #00FFFF;
}