header {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  position: absolute;
  z-index: 1000;
  left: 0;
  top: 0;
  height: 72px;
  padding: 0 30px;
}
header .title {
  color: white;
  font-size: 24px;
  font-weight: bold;
}
header nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex: 1;
}
header nav a {
  color: white;
}
header nav .nav-item {
  margin-left: 20px;
}
@media (max-width: 441px) {
  header nav {
    background-color: white;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
    flex-direction: column;
    justify-content: flex-start;
    align-items: flex-start;
    transition: all ease 0.2s;
    position: absolute;
    right: 0;
    top: 60px;
    visibility: visible;
    opacity: 1;
    width: 30vw;
  }
  header nav a {
    color: black;
    font-size: 14px;
  }
  header nav .nav-item {
    padding: 10px;
    width: 100%;
    margin-left: 0;
    margin-top: 10px;
    margin-bottom: 10px;
  }
  header nav.toggled {
    opacity: 0;
    visibility: hidden;
  }
}
header .toggle {
  display: none;
  color: white;
  font-size: 20px;
}
@media (max-width: 441px) {
  header .toggle {
    display: block;
  }
}

.banner {
  display: flex;
  justify-content: center;
  width: 100%;
  color: white;
  position: relative;
}
.banner .info_block {
  margin: 120px auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.banner .info_block .title {
  margin-bottom: 40px;
  max-width: 840px;
  font-size: 65px;
  font-weight: bold;
  text-align: center;
}
.banner .info_block .hide {
  display: none;
}
.banner .info_block .summary {
  display: block;
  font-size: 16px;
}
.banner .info_block .summary span {
  display: inline-block;
  padding: 0 30px;
}
.banner .info_block .summary span:nth-child(even) {
  border-left: 1px solid white;
  border-right: 1px solid white;
}
.banner.article {
  height: 504px;
}
.banner.article .info_block .title {
  font-size: 3rem;
}
.banner.about {
  height: 60vh;
}
.banner.underline .info_block .title {
  font-size: 4rem;
  text-decoration: underline;
  text-decoration-color: #006fdd;
}
.bg {
  position: absolute;
  z-index: -1;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-repeat: no-repeat;
}
.bg.article {
  background-image: url('/static/images/article.png');
}
.bg.about {
  background-image: url('/static/images/about_bg.png');
}
.bg.community {
  background-image: url('/static/images/community.png');
}
.bg.news {
  background-image: url('/static/images/community.png');
}
.bg.progress {
  background-image: url('/static/images/community.png');
}
.bg.conference {
  background-image: url('/static/images/community.png');
}

main {
  flex: 1;
}

footer {
  background-color: black;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 15px;
}
footer .contact-item {
  margin: 0 25px;
  color: white;
  font-size: 13px;
}
footer .contact-item a {
  color: white;
  transition: all ease 0.1s;
}
footer .contact-item a:hover {
  opacity: 0.8;
}
@media (max-width: 441px) {
  footer {
    flex-direction: column;
  }
  footer .contact-item:not(:last-child) {
    margin-bottom: 15px;
  }
}

.layout-with-header-and-footer {
  display: flex;
  min-height: 100vh;
  width: 100%;
  flex-direction: column;
}
.layout-with-header-and-footer main {
  flex-shrink: 0;
}