.content {
  padding: 20px;
  height: 100%;
  width: 944px;
  margin-left: auto;
  margin-right: auto;
}
.fold {
  width: 20px;
  float: left;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -khtml-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}
.number {
  width: 45px;
  float: left;
  margin-right: 10px;
  text-align: right;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -khtml-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}
.line {
}