/* ── Site Header & Navigation ──────────────────── */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  z-index: 11;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem calc((100% - min(90vw, 1200px)) / 2);
  transition: background 0.3s, box-shadow 0.3s, padding-top 0.3s, padding-bottom 0.3s;
}

.site-header.scrolled {
  background: var(--surface-overlay);
  backdrop-filter: var(--blur-panel);
  -webkit-backdrop-filter: var(--blur-panel);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.4);
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.wordmark-group {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

@media (max-width: 768px) {
  .wordmark-group {
    flex-wrap: wrap;
    justify-content: center;
    width: 100%;
    max-width: 85vw;
    gap: 0.1rem;
  }

  .wordmark-group .audio-toggle {
    flex-basis: 100%;
  }
}

.wordmark {
  filter: var(--glow-logo);
}

.wordmark img {
  width: clamp(160px, 22vw, 320px);
  height: auto;
  filter: var(--glow-logo);
  transition: filter 0.05s, transform 0.05s;
}

/* Nav */
.site-nav {
  display: flex;
  gap: 0;
  list-style: none;
}

.site-nav li {
  position: relative;
  overflow: hidden;
  padding: 0.5rem 1.2rem;
}

.site-nav li::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: var(--nav-bg);
  background-size: cover;
  background-position: center;
  opacity: 0;
  transition: opacity 0.15s;
  z-index: 0;
}

.site-nav li:hover::before {
  opacity: 1;
}

.site-nav a {
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.15s;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.5);
  position: relative;
  z-index: 1;
}

.site-nav li:hover a {
  color: #000;
}

/* Inactive nav items */
.site-nav li.inactive {
  opacity: 0.3;
  pointer-events: none;
}

.site-nav li.inactive:hover::before {
  opacity: 0;
}

.site-nav li.inactive:hover a {
  color: inherit;
}

/* Nav wrapper: fixed top-right on desktop (lives outside <header> in HTML) */
.nav-wrapper {
  position: fixed;
  top: 0;
  right: 0;
  z-index: 12;
  display: flex;
  align-items: center;
  padding: 1.5rem calc((100% - min(90vw, 1200px)) / 2);
  transition: padding-top 0.3s, padding-bottom 0.3s;
}

.site-header.scrolled ~ .nav-wrapper {
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.site-nav .nav-home {
  display: none;
}

.nav-close {
  display: none;
}

/* Burger button */
.burger {
  display: none;
  background: var(--surface-overlay);
  backdrop-filter: var(--blur-panel);
  -webkit-backdrop-filter: var(--blur-panel);
  border: 1px solid var(--border-default);
  border-radius: 50%;
  width: 48px;
  height: 48px;
  cursor: pointer;
  z-index: 13;
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s;
}

.burger:hover {
  border-color: var(--color-cyan);
}

/* Mobile nav */
@media (max-width: 768px) {
  .site-header {
    position: sticky;
    justify-content: center;
    padding: 1rem 1rem;
    background: rgba(16, 19, 35, 0.97);
  }

  .burger {
    display: flex;
  }

  .nav-wrapper {
    position: fixed;
    inset: 0;
    z-index: 9999;
    padding: 0;
    background: rgba(16, 19, 35, 0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
  }

  .nav-wrapper.open {
    opacity: 1;
    visibility: visible;
  }

  .nav-wrapper .site-nav {
    flex-direction: column;
    align-items: flex-start;
    gap: 2rem;
    padding-left: 2rem;
  }

  .nav-wrapper .site-nav a {
    font-size: 1.4rem;
  }

  .site-nav .nav-home {
    display: list-item;
  }

  .nav-close {
    position: absolute;
    bottom: 2rem;
    right: 2rem;
    background: none;
    border: 1px solid var(--border-default);
    border-radius: 50%;
    width: 48px;
    height: 48px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: border-color 0.2s;
  }

  .nav-close:hover {
    border-color: var(--color-cyan);
  }

  .nav-close svg {
    width: 20px;
    height: 20px;
    stroke: var(--color-text);
    stroke-width: 2;
    fill: none;
  }

  .wordmark {
    position: static;
    transform: none;
    width: auto;
    text-align: center;
    margin-bottom: 1.5rem;
  }

  .wordmark img {
    width: 85vw;
    max-width: none;
  }
}