body {
  padding: 0;
  margin: 0;
  display: flex;
  justify-content: center;
}

.main-wrap {
  margin-top: 20px;
  width: 90%;
  max-width: 800px;
  background-color: ghostwhite;
  padding: 10px;
  box-sizing: border-box;
}

.title {
  margin: 0;
  font-size: 28px;
}

.document-link {
  display: block;
  margin-top: 10px;
  font-size: 20px;
  text-decoration: none;
}

.demo-wrap {
  margin-top: 20px;
}

.input-title {
  font-size: 18px;
  margin-bottom: 20px;
}

#input ,
#result {
  width: 80%;
  height: 150px;
  border: 1px solid #ccc;
  line-height: 1.5;
  font-size: 18px;
  outline: none;
  padding: 10px;
  margin-bottom: 15px;
}