.header {
  position: sticky;
  width: 100%;
  top: 0;
  background-color: var(--background-color);
  user-select: none;
  z-index: 20;
  overflow: hidden;
  transition: var(--main-transition);
}
.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  position: relative;
}
.header .logo {
  color: var(--main-color);
  font-size: 2rem;
  margin: 0 20px;
  height: 72px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: bold;
  font-family: var(--logo-font);
}
@media (max-width: 767px) {
  .header .logo {
    width: 100%;
    height: 50px;
  }
}
@media (max-width: 450px) {
  .header .logo {
    font-size: 1.5rem;
  }
}
@media (max-width: 360px) {
  .header .logo {
    font-size: 1.2rem;
  }
}
.header .main-nav {
  display: flex;
}
@media (max-width: 767px) {
  .header .main-nav {
    margin: auto;
  }
}
.header .main-nav > li > a {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 72px;
  position: relative;
  color: var(--main-color);
  font-family: var(--link-font);
  font-weight: bold;
  font-size: 16px;
  padding: 0 20px;
  transition: var(--main-transition);
  overflow: hidden;
}
@media (max-width: 767px) {
  .header .main-nav > li > a {
    padding: 10px;
    height: 40px;
  }
}
@media (max-width: 450px) {
  .header .main-nav > li > a {
    font-size: 14px;
    padding: 8px;
  }
}
@media (max-width: 360px) {
  .header .main-nav > li > a {
    font-size: 12px;
  }
}
.header .main-nav > li > a::before {
  content: "";
  position: absolute;
  width: 100%;
  height: 2px;
  background-color: var(--main-color);
  bottom: 0;
  left: -100%;
  transition: var(--main-transition);
}
.header .main-nav > li > a:hover::before {
  left: 0;
}