/* ==========================================================================
   Header & Navigation
   ========================================================================== */
header {
  position: fixed;
  top: 1rem;
  left: 1rem;
  right: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 3rem;
  background-color: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 50px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
  z-index: 1000;
  transition: all 0.3s ease;
}

header.scrolled {
  padding: 0.65rem 2.5rem;
  top: 0.5rem;
  background-color: rgba(255, 255, 255, 0.95);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.08);
}

.logo {
  font-family: 'Shippori Mincho', serif;
  font-weight: bold;
  font-size: 1.5rem;
  color: var(--primary);
  white-space: nowrap;
  flex-shrink: 0;
}

.logo a {
  color: inherit;
  text-decoration: none;
}

/* Nav Desktop */
nav ul.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
  margin: 0;
  padding: 0;
}

.nav-link {
  text-decoration: none;
  color: var(--text-dark);
  font-weight: 500;
  white-space: nowrap;
  transition: color 0.2s ease;
  display: inline-flex;
  align-items: center;
}

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

.nav-link-ja {
  display: inline;
}

.nav-link:hover {
  color: var(--primary);
}

.mobile-nav-header,
.mobile-nav-footer {
  display: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.btn-cta-small {
  background-color: var(--primary);
  color: white;
  padding: 0.5rem 1.5rem;
  border-radius: 25px;
  font-weight: bold;
  text-decoration: none;
  white-space: nowrap;
  flex-shrink: 0;
  font-size: 0.95rem;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.btn-cta-small:hover {
  transform: translateY(-2px);
  background-color: var(--text-dark);
}

/* Hamburger Button */
.hamburger-btn {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  min-width: 42px;
  min-height: 42px;
  background-color: var(--bg-cream);
  border: 1.5px solid var(--border-dashed);
  border-radius: 50%;
  cursor: pointer;
  padding: 0;
  position: relative;
  z-index: 1002;
  transition: all 0.25s ease;
  -webkit-tap-highlight-color: transparent;
}

.hamburger-btn:hover {
  background-color: #FAF4EB;
  border-color: var(--secondary);
}

.hamburger-bar {
  width: 18px;
  height: 2px;
  background-color: var(--primary);
  border-radius: 2px;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.2s ease, background-color 0.3s ease;
  transform-origin: center;
}

.hamburger-btn.is-active {
  background-color: var(--primary);
  border-color: var(--primary);
}

.hamburger-btn.is-active .hamburger-bar {
  background-color: #FFFFFF;
}

.hamburger-btn.is-active .hamburger-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger-btn.is-active .hamburger-bar:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.hamburger-btn.is-active .hamburger-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Header Responsive Adjustments for Tablet & 125%/150% Scaling Desktops */
@media (max-width: 1320px) {
  header {
    padding: 0.85rem 1.75rem;
  }
  header.scrolled {
    padding: 0.6rem 1.5rem;
  }
  .logo {
    font-size: 1.3rem;
  }
  nav ul.nav-links {
    gap: 1.15rem;
  }
  .nav-link {
    font-size: 0.925rem;
  }
  .btn-cta-small {
    padding: 0.5rem 1.15rem;
    font-size: 0.875rem;
  }
}

@media (max-width: 992px) {
  header {
    padding: 0.75rem 1.25rem;
    left: 0.5rem;
    right: 0.5rem;
  }
  header.scrolled {
    padding: 0.55rem 1rem;
  }
  .logo {
    font-size: 1.15rem;
  }
  nav ul.nav-links {
    gap: 0.75rem;
  }
  .nav-link {
    font-size: 0.85rem;
  }
  .btn-cta-small {
    padding: 0.45rem 0.85rem;
    font-size: 0.825rem;
  }
}

@media (max-width: 768px) {
  header {
    padding: 0.6rem 0.85rem 0.6rem 1.15rem;
    left: 0.5rem;
    right: 0.5rem;
    top: 0.5rem;
    border-radius: 40px;
  }

  header.scrolled {
    padding: 0.5rem 0.75rem 0.5rem 1rem;
    top: 0.35rem;
  }

  .logo {
    font-size: 1.05rem;
  }

  .header-actions {
    gap: 0.4rem;
  }

  .btn-cta-small {
    padding: 0.4rem 0.75rem;
    font-size: 0.78rem;
  }

  .hamburger-btn {
    display: flex;
  }

  /* Fullscreen / Drawer Navigation */
  nav#main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    height: 100dvh;
    background: linear-gradient(180deg, rgba(254, 252, 248, 0.98) 0%, rgba(246, 240, 230, 0.99) 100%);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: stretch;
    padding: 5.5rem 1.5rem 2rem;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1), visibility 0.3s cubic-bezier(0.4, 0, 0.2, 1), transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 999;
  }

  nav#main-nav.is-open {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
  }

  .mobile-nav-header {
    display: block;
    text-align: center;
    margin-bottom: 1.25rem;
    padding-bottom: 0.85rem;
    border-bottom: 1px dashed #D8CDBF;
  }

  .mobile-nav-logo {
    font-family: 'Shippori Mincho', serif;
    font-size: 1.35rem;
    font-weight: bold;
    color: var(--primary);
    letter-spacing: 0.05em;
  }

  .mobile-nav-sub {
    font-size: 0.8rem;
    color: var(--secondary);
    font-weight: 500;
    margin-top: 0.25rem;
  }

  nav ul.nav-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    list-style: none;
    padding: 0;
    margin: 0;
    width: 100%;
  }

  .nav-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    padding: 0.75rem 1.25rem;
    background-color: rgba(255, 255, 255, 0.7);
    border: 1px solid rgba(216, 205, 191, 0.6);
    border-radius: 14px;
    text-decoration: none;
    transition: all 0.2s ease;
    box-shadow: 0 2px 8px rgba(89, 54, 34, 0.02);
  }

  .nav-link:active,
  .nav-link:hover {
    background-color: #FFFFFF;
    border-color: var(--secondary);
    transform: translateX(4px);
    box-shadow: 0 4px 12px rgba(89, 54, 34, 0.08);
  }

  .nav-link-en {
    display: inline-block;
    font-size: 0.725rem;
    font-weight: 700;
    color: var(--secondary);
    letter-spacing: 0.08em;
  }

  .nav-link-ja {
    font-family: 'Shippori Mincho', serif;
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--primary);
  }

  .mobile-nav-footer {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.6rem;
    margin-top: 1.25rem;
    padding-top: 1rem;
    border-top: 1px dashed #D8CDBF;
  }

  .btn-drawer-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    width: 100%;
    max-width: 320px;
    padding: 0.85rem 1.5rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: #FFFFFF;
    font-weight: 700;
    font-size: 0.95rem;
    border-radius: 50px;
    text-decoration: none;
    box-shadow: 0 4px 14px rgba(89, 54, 34, 0.2);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
  }

  .btn-drawer-cta:active {
    transform: scale(0.98);
  }

  .mobile-nav-note {
    font-size: 0.725rem;
    color: #7A695B;
    margin: 0;
  }

  /* Body scroll lock when menu is open */
  body.menu-open {
    overflow: hidden;
    touch-action: none;
  }
}