*, :after, :before {
  box-sizing: border-box;
}
body {
  color: #43484d;
}
.nav {
  display: flex;
  flex-direction: row;
  align-items: center;
  border-bottom: 1px solid #f5f5f5;
  line-height: 30px;
  margin-bottom: 10px;
}
.nav .nav-tab {
  cursor: pointer;
  position: relative;
  flex: 1;
  text-align: center;
  font-size: 16px;
  font-weight: bold;
  border-bottom: 3px solid transparent;
  transition: border .2s cubic-bezier(0.43, 0.37, 1, 1);
}
.nav span.active .active-img {
  display: block;
}
.active-img {
  display: none;
  position: absolute;
  left: 0;
  right: 0;
  bottom: -12px;
  width: 100%;
  height: 10px;
  background: url("/images/active.png") no-repeat center;
  background-size: 150px 10px;
}
.section-tab {
  display: none;
  margin: 10px 30px;
}
.section-tab.active {
  display: block;
}
.version-content {
  position: relative;
  width: 100%;
  z-index: 2;
}
.version-content .versions {
  position: static;
  margin-bottom: 40px;
  padding: 20px 0;
}
.version-content:after {
  content: "";
  position: absolute;
  width: 5px;
  top: 0;
  left: 0;
  bottom: 0;
  margin-left: -2.5px;
  background-color: #e6eaf5;
}
.version-content:before{
  content: "";
  width: 20px;
  height: 5px;
  border-radius: 4px;
  position: absolute;
  left: 50%;
  margin-left: -10px;
  background-color: #e6eaf5;
}
.version-content:before{
  left: 0;
  top: 0;
}
.version-content .versions .version {
  width: 100%;
  top: 0;
  left: 0;
  margin-top: 15px;
  padding-left: 35px;
  padding-right: 0;
  position: relative;
  margin-left: 0;
}
.version-content .versions .version:before {
  border-right: 13px solid #9d9d9d;
}
.version-content .dot {
  z-index: 10;
  position: absolute;
  left: -8px;
  background-color: #fff;
  border-radius: 50%;
  width: 16px;
  height: 16px;
  border: 2px solid #007aff;
  top: 12px;
}
.version-content .ver {
  font-size: 30px;
  font-weight: 600;
  margin-bottom: 16px;
}
.version-content .date {
  opacity: 0.7;
  font-size: 16px;
  line-height: 24px;
  margin-bottom: 24px;
  padding-bottom: 10px;
  border-bottom: 1px solid #ddd;
}
.version-content .versions .version+.version{
  margin-top: 50px;
}
.version-content h5{
  font-size: 18px;
  margin: 12px 0;
}