* {
  margin: 0;
  padding: 0;
}
body {
  background-color: rgba(0, 0, 0, 0.904);
  color: white;
  margin-left: 10vw;
  margin-right: 10vw;
}
h1,
h2 {
  font-size: 30px;
  text-align: center;
  margin-bottom: 20px;
  margin-top: 20px;
}
h1,
h2,
h4 {
  color: aquamarine;
}
h4 {
  text-decoration: dashed;
  margin-top: 20px;
  margin-bottom: 20px;
}
a {
  color: white;
  text-decoration: none;
}
a:hover {
  color: aquamarine;
}
img {
  width: 50%;
  height: 50vh;
  display: block;
  position: relative;
  margin-left: auto;
  margin-right: auto;
  margin-top: 20px;
  margin-bottom: 60px;
  object-fit: contain;
}
.about,
.author,
.content,
.started,
.comments,
.header,
.paragraph,
.link,
.image,
.text,
.section,
.nav,
.html5,
.tables,
.list,
.input,
.forms,
.textarea,
.select {
  margin-top: 20px;
  margin-bottom: 20px;
}
pre {
  font-weight: bold;
  margin: 20px 0 20px 0;
  color: aquamarine;
}
div {
  height: 40vh;
}
.content {
  height: 100vh;
}
.tables {
  height: 60vh;
}
span {
  color: aquamarine;
  font-weight: bold;
}

/* for smaller screens */
@media screen and (max-width: 500px) {
  .input {
    height: 80vh;
  }
  .tables {
    height: 80vh;
  }
  .forms {
    height: 70vh;
  }
}