*,
*:after,
*:before {
  box-sizing: border-box;
}
body,
html {
  margin: 0;
  font-family: sans-serif;
  color: #333;
}
.mainBody {
  max-width: 800px;
  margin: 20px auto;
}
.mainTextarea {
  width: 100%;
  display: block;
  margin: 0 auto;
  border: solid 1px #999;
  resize: none;
  height: 300px;
  padding: 5px;
}
.divider {
  margin: 10px auto;
  border-top: solid 1px transparent;
}