html {
  height: 100%;
}

body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: Tahoma, sans-serif;
  line-height: 1.4;

  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  justify-content: center;
  align-items: center;
  align-content: center;

  font-size: 4vmin;
}

#content {
  width: 100%;
  height: 100%;

  display: flex;
  flex-direction: column;
  flex-wrap: nowrap;
  justify-content: center;
  align-items: center;
  align-content: center;

  background-color: black;
}

.slide {
  width: 80%;
  height: 80%;
  color: gray;

  display: none;
}

.slide.active {
  display: block;
}

.slide > .head {
  text-align: center;
}

.slide > .body {
  display: flex;
  flex-direction: column;
  flex-wrap: nowrap;
  justify-content: center;
  align-items: center;
  align-content: center;
  height: 70%;
}

.slide > .body > p {
  white-space: nowrap;
  margin: 2vmin;
}

.slide > .body > pre {
  overflow: scroll;
}

.slide pre > code.hljs {
  min-width: 50vw;
  font-size: 3vmin;
}

a:visited, a:focus {
  color: blue;
  border: none;
  outline: none;
}