/* The home page masthead, shared by every site section. */
header.site-navigation {
  display: block; position: sticky; top: 0; z-index: 50;
  width: 100%; max-width: none; margin: 0; padding: 0;
  background: rgba(11,18,38,.97); color: #eceff1;
  border-bottom: 1px solid #4b5c80; box-shadow: 0 8px 28px rgba(6,12,26,.22);
  font-family: "Space Grotesk", Verdana, sans-serif; letter-spacing: normal;
}
.site-navigation *, .site-navigation *::before, .site-navigation *::after { box-sizing: border-box; }
.site-navigation .header-layout { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 5.5rem; height: auto; max-width: 1500px; margin: auto; padding: 0 2rem; }
.site-navigation .header-brand { display: inline-flex; align-items: center; gap: .6rem; flex-shrink: 0; color: #eceff1; text-decoration: none; font-weight: 600; white-space: nowrap; }
.site-navigation .header-brand > span:first-child { font-size: 2rem; font-weight: 700; letter-spacing: -.06em; }
.site-navigation .header-brand > svg { width: 22px; height: 22px; flex-shrink: 0; }
.site-navigation .header-brand > span:last-child { font-size: 1.25rem; color: #eceff1; }
.site-navigation .header-actions { display: flex; align-items: center; gap: .625rem; }
.site-navigation .header-cta { display: inline-flex; align-items: center; justify-content: center; min-height: 3rem; padding: .75rem 1rem; border-radius: .375rem; background: #70dfa9; color: #0b1226; font-size: 1rem; font-weight: 700; text-decoration: none; white-space: nowrap; }
.site-navigation .header-cta:hover { background: #b0f1cf; }
.site-navigation #menuBtn { display: inline-flex; align-items: center; justify-content: center; min-width: 44px; min-height: 48px; padding: .5rem; background: transparent; color: #eceff1; border: 1px solid #68799d; border-radius: .375rem; cursor: pointer; }
.site-navigation .header-nav { display: none; }
.site-navigation #mobileMenu { display: flex; flex-direction: column; gap: .25rem; max-height: calc(100dvh - 5.5rem); overflow-y: auto; padding: 1rem 1.25rem; background: #0b1226; border-top: 1px solid #33417a; }
.site-navigation #mobileMenu.hidden { display: none; }
.site-navigation .header-nav > a, .site-navigation #mobileMenu > a { display: block; padding: .625rem 1rem; border-radius: .375rem; color: #eceff1; font-size: 1.25rem; line-height: 1.5; font-weight: 600; text-decoration: none; }
.site-navigation #mobileMenu > a { padding: .75rem; }
.site-navigation .header-nav > a:hover, .site-navigation #mobileMenu > a:hover { background: #1b2450; color: #70dfa9; }
.site-navigation a:focus-visible, .site-navigation button:focus-visible { outline: 3px solid #fecc00; outline-offset: 4px; }
@media (max-width: 639px) {
  .site-navigation .header-layout { padding-inline: 1rem; gap: .5rem; flex-wrap: wrap; }
  .site-navigation .header-brand { gap: .3rem; }
  .site-navigation .header-brand > span:last-child { display: none; }
  .site-navigation .header-cta { padding-inline: .75rem; font-size: .9375rem; }
  .site-navigation .header-actions { gap: .375rem; }
}
@media (min-width: 1024px) {
  .site-navigation .header-layout { display: grid; grid-template-columns: minmax(0,1fr) auto; row-gap: 0; padding-top: 1rem; }
  .site-navigation .header-brand > span:first-child { font-size: 2.5rem; }
  .site-navigation .header-brand > span:last-child { font-size: 1.5rem; }
  .site-navigation .header-actions { grid-column: 2; grid-row: 1; gap: 1rem; }
  .site-navigation .header-cta { min-height: 3.25rem; padding-inline: 1.5rem; font-size: 1.125rem; }
  .site-navigation .header-nav { display: flex; grid-column: 1 / -1; grid-row: 2; justify-content: center; align-items: center; flex-wrap: wrap; gap: .25rem 1rem; margin-top: 1rem; padding-block: .5rem; border-top: 1px solid #33417a; }
  .site-navigation > .header-nav { max-width: 1436px; margin-inline: auto; }
  .site-navigation #menuBtn, .site-navigation #mobileMenu { display: none; }
}
/* Preserve the home and book pages' existing fixed masthead spacing. */
header.site-navigation.fixed { position: fixed; }