html,
body {
  min-height: 100vh;
}

body {
  font-family: sans-serif;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  min-width: 1280px;
  max-width: 1920px;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.main {
  flex-grow: 1;
  padding-bottom: 36px;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 1280px;
  height: 162px;
  margin: auto;
}
.header .nav {
  width: 720px;
}
.nav {
  display: flex;
  justify-content: space-between;
}
.nav a {
  display: block;
  padding: 18px;
  border-radius: 5px;
  text-decoration: none;
  font-size: 22px;
  font-weight: 100;
  color: #808080;
}
.nav .current a {
  color: #fff;
  background-color: #1b75ba;
}

.footer {
  background-color: #202020;
}
.footer .content-info {
  display: flex;
  width: 1280px;
  height: 190px;
  margin: auto;
  align-items: center;
}
.footer .content-info .qrcode {
  width: 88px;
  margin: 0 10px 0 98px;
}
.footer .content-info :not(.qrcode) + .address {
  margin-left: 98px;
}
.footer .content-info .address {
  margin-right: 48px;
}
.footer .content-info .address,
.footer .content-info .address a {
  font-style: normal;
  color: rgba(255, 255, 255, 0.43);
  font-size: 14px;
  text-decoration: none;
}
.footer .content-info .address p {
  margin: 0;
}
.footer .copyright {
  background-color: #000;
  line-height: 57px;
  text-align: center;
  font-size: 14px;
  letter-spacing: 1.4px;
  color: #fff;
  opacity: 0.6;
}

.column-header {
  box-sizing: border-box;
  text-align: center;
  height: 218px;
  padding-top: 40px;
}
.column-header .en {
  font-family: 'Microsoft Yi Baiti';
  text-transform: uppercase;
  font-size: 36px;
  height: 38px;
  color: #77a5c5;
}
.column-header .cn {
  font-size: 48px;
  font-weight: 100;
  color: #fff;
}
.column-header .line {
  display: inline-block;
  width: 92px;
  height: 5px;
  background-color: #d77d2b;
}

.m-auto {
  margin: auto;
}