.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 300;
  color: var(--color-white);
  transition: background-color .3s ease, color .3s ease, box-shadow .3s ease;
}

.site-header.scrolled {
  color: var(--color-deep);
  background: rgba(255, 255, 255, .96);
  box-shadow: 0 8px 30px rgba(10, 45, 55, .06);
}

.nav {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 32px;
  padding-block: var(--nav-pad-y);
}

.logo {
  display: block;
  width: var(--logo-width);
  line-height: 0;
}

.logo-img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: contain;
}

.logo-white {
  display: block
}

.logo-dark {
  display: none
}

.site-header.scrolled .logo-white {
  display: none
}

.site-header.scrolled .logo-dark {
  display: block
}

/* Navigation */
.nav-menu {
  justify-self: end;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-list li {
  display: block;
}

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  /*min-height:40px;*/
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: .13em;
  color: inherit;
  padding: 10px 15px 11px;
}

.nav-link:not(.nav-book)::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 3px;
  height: 1px;
  background: currentColor;
  transition: right .25s ease;
}

.nav-link:not(.nav-book):hover::after {
  right: 0;
}

.site-header:not(.scrolled) .nav-link:not(.nav-book) {
  color: var(--color-white);
}

.site-header.scrolled .nav-link:not(.nav-book) {
  color: var(--color-deep);
}

/* Same nav item, only visual modifier */
.nav-book {
  /*padding-inline:18px;*/
  border-radius: var(--radius-sm);
  background: var(--color-red);
  color: var(--color-white);

   transition:
    background-color .35s ease,
    color .35s ease;
}

.nav-book:hover {

  background: var(--color-white);
  color: var(--color-red);

}


/*.nav-book:visited{
  color:var(--color-white);
}*/

/* Menu toggle */
.menu-btn {
  display: none;
  width: 44px;
  height: 44px;
  border: 0;
  background: transparent;
  padding: 10px 0 10px 12px;
  color: inherit;
}

.menu-btn span {
  display: block;
  height: 1px;
  margin: 7px 0;
  background: currentColor;
}

@media(max-width:900px) {
  .nav {
    position: relative;
    grid-template-columns: 44px 1fr 44px;
    gap: 0;
    padding-block: var(--nav-pad-y-mobile);
  }

  .logo {
    grid-column: 2;
    justify-self: center;
    width: var(--logo-width-mobile);
  }

  .menu-btn {
    display: block;
    grid-column: 3;
    justify-self: end;
  }

  .nav-menu {
    position: fixed;
    top: var(--mobile-header-height, 72px);
    left: 0;
    right: 0;
    width: 100%;
    display: none;
    background: rgba(255, 255, 255, .98);
    color: var(--color-deep);
    box-shadow: 0 18px 35px rgba(0, 0, 0, .08);
  }

  .nav-menu.open {
    display: block;
  }

  .nav-list {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
    /*padding:10px 0 18px;*/
  }

  .nav-list li {
    width: 100%;
  }

  .nav-link {
    width: 100%;
    min-height: 0;
    justify-content: flex-start;
    padding: 32px var(--page-padding-x);
    color: var(--color-deep);
  }

  /* Mobile menu has a white background, so links must stay dark
     regardless of the header's transparent/scrolled state. */
  .site-header:not(.scrolled) .nav-menu .nav-link:not(.nav-book),
  .site-header.scrolled .nav-menu .nav-link:not(.nav-book) {
    color: var(--color-deep);
  }

  .nav-link::after {
    display: none;
  }

  .nav-book {
    margin: 0;
    border-radius: 0;
    background: var(--color-red);
    color: var(--color-white);
  }

  .nav-book,
  .nav-book:visited {
    color: var(--color-white);
  }

  .site-header:not(.scrolled) .menu-btn span {
    background: var(--color-white);
  }

  .site-header.scrolled .menu-btn span {
    background: var(--color-deep);
  }
}


/* Layering: navigation must always stay above the GO7 iframe. */
.site-header {
  z-index: 300;
}

@media(max-width:900px) {
  .nav-menu {
    z-index: 310;
  }
}