body,
html {
  padding: 0;
  margin: 0;
  height: 100%;
  background: #eee;
}
.content-title {
  background-color: #2c3e50;
  color: #fff;
  padding: 10px;
  font-size: 18px;
}
.markdown-content {
  width: 1280px;
  margin: 20px auto;
  border:1px solid #ddd;
  padding: 20px;
}