body {
  background: #ccc;
  font-family: 'Open Sans', sans-serif;
}

section {
  position: relative;
  padding: 0 10px;
}

article {
  position: relative;
  width: 800px;
  margin: 20px auto 0;
  z-index: 500;
  background: #ffffff;
  padding: 20px 50px;
  border-top: 5px solid tomato;
}

article h2 {
  color: #283f53;
  font-weight: 300;
  text-transform: uppercase;
  letter-spacing: 1px;
}

pre {
    font-size: 110%;
    background-color: #eaeaea;
    padding: 15px;
}

.on_github {
  text-align: right;
}
.github {
  color: #313131;
  font-size: 1.2rem; 
}
.github svg {
  vertical-align: middle;
  margin-right: 10px; 
}
.github:hover {
  color: tomato; 
}


.spoiler_1, .spoiler_2, .spoiler_3 {
    border-left: 2px solid #999;
    padding-left: 10px;
    margin: 10px 0;
    color: #999;
}

.btn {
  border-radius: 2px;
  background-color: tomato;
  border: 1px solid tomato;
  padding: 4px 8px;
  color: #fff;
  margin-top:0px;
  cursor: pointer;
  outline: none;
}
.btn:hover {
    background: #CC452D;
    color: #fff;
}