html,
body {
  height: 100%;
}
body {
  font: 16px tahoma, arial, "Hiragino Sans GB", "Microsoft Yahei";
  line-height: 1.5;
  background: #eee;
}
.container {
  max-width: 970px;
  background: #fff;
}
.posts {
  font-size: 16px;
  margin: 1em auto;
  max-width: 620px;
  padding-bottom: 2em;
}
.posts .post .dt {
  font-size: 11px;
  color: #bbb;
}
.posts .post hr {
  border-top: 1px solid #ccc;
}
.navbar {
  margin-bottom: 0;
}
#header {
  margin: 1em auto;
  text-align: center;
}
#nav {
  text-align: center;
}
#nav .cats {
  width: 80%;
  font-size: 18px;
  text-align: center;
  margin: 1em auto;
}
#footer {
  margin: 1em auto;
  text-align: center;
}
#show-background-trigger {
  display: block;
  cursor: pointer;
  padding: 10px;
  width: 50px;
  height: 50px;
  line-height: 30px;
  margin: 0 auto;
  background: #eee;
  text-align: center;
  border: 1px splid #bbb;
}
#show-background-trigger:hover {
  background: #bbb;
}