/* ========== FLOATING HEADER - LayerX style ========== */
.site-header {
  position: fixed;
  top: var(--header-offset);
  left: var(--header-offset);
  right: var(--header-offset);
  z-index: var(--z-header);
  display: flex;
  align-items: center;
  justify-content: space-between;
  pointer-events: none;
}

.site-header > * {
  pointer-events: auto;
}

.header-inner {
  display: contents;
}

/* Logo (hidden in LayerX style - use Menu button instead) */
.header-logo {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  pointer-events: auto;
  opacity: 0;
  display: none;
}

.header-logo img {
  height: 22px;
  width: auto;
}

.logo-dark { display: block; }
.logo-light { display: none; }

/* Menu button - top left floating pill */
.header-menu-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 14px var(--space-6);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-full);
  font-family: var(--font-en);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-dark);
  box-shadow: var(--shadow-md);
  transition: all var(--duration-fast) var(--ease-out);
  cursor: pointer;
}

.header-menu-btn:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-1px);
}

.header-menu-btn-icon {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  width: 20px;
  height: 14px;
  flex-direction: column;
  justify-content: center;
}

.header-menu-btn-icon span {
  display: block;
  width: 14px;
  height: 2px;
  background-color: var(--color-primary);
  border-radius: 1px;
}

.header-menu-btn-icon span:nth-child(2) {
  width: 10px;
  margin-top: 3px;
}

/* Back-to-top button - top right (temporarily hidden; restore by changing display back to inline-flex) */
.header-top-btn {
  display: none !important;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: 50%;
  color: var(--color-primary);
  box-shadow: var(--shadow-md);
  transition: all var(--duration-fast) var(--ease-out);
  cursor: pointer;
  position: relative;
}

.header-top-btn:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.header-top-btn svg {
  width: 18px;
  height: 18px;
}

/* Progress ring around the top button */
.header-top-btn::before {
  content: '';
  position: absolute;
  inset: -1px;
  border: 1.5px solid transparent;
  border-top-color: var(--color-primary);
  border-right-color: var(--color-primary);
  border-radius: 50%;
  transform: rotate(-45deg);
  opacity: 0.7;
}

/* ========== PC: Persistent header navigation (centered) ========== */
.header-nav {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-md);
  padding: 6px var(--space-3);
  pointer-events: auto;
}

.header-nav .nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  list-style: none;
  margin: 0;
  padding: 0;
}

.header-nav .nav-item {
  position: relative;
}

.header-nav .nav-link {
  display: inline-flex;
  align-items: center;
  padding: 10px var(--space-4);
  font-family: var(--font-en);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-dark);
  border-radius: var(--radius-full);
  transition: color var(--duration-fast) var(--ease-out),
              background-color var(--duration-fast) var(--ease-out);
  text-decoration: none;
  white-space: nowrap;
}

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

.header-nav .nav-link--contact {
  background-color: var(--color-primary);
  color: var(--color-white);
  padding: 10px var(--space-5);
}

.header-nav .nav-link--contact:hover {
  background-color: var(--color-dark);
  color: var(--color-white);
}

/* Indicator that an item has a dropdown */
.header-nav .nav-item--has-sub > .nav-link::after {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-left: var(--space-2);
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: translateY(-2px) rotate(45deg);
  transition: transform var(--duration-fast) var(--ease-out);
}

.header-nav .nav-item--has-sub:hover > .nav-link::after,
.header-nav .nav-item--has-sub:focus-within > .nav-link::after {
  transform: translateY(0) rotate(-135deg);
}

/* Dropdown panel */
.header-nav .nav-submenu {
  position: absolute;
  top: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  min-width: 220px;
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-lg, 12px);
  box-shadow: var(--shadow-lg);
  padding: var(--space-3);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity var(--duration-fast) var(--ease-out),
              transform var(--duration-fast) var(--ease-out),
              visibility var(--duration-fast) var(--ease-out);
  z-index: 1;
}

.header-nav .nav-submenu::before {
  content: '';
  position: absolute;
  top: -10px;
  left: 0;
  right: 0;
  height: 10px;
}

.header-nav .nav-item--has-sub:hover > .nav-submenu,
.header-nav .nav-item--has-sub:focus-within > .nav-submenu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.header-nav .nav-submenu ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.header-nav .nav-submenu a {
  display: block;
  padding: 10px var(--space-4);
  font-family: var(--font-ja);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-dark);
  border-radius: var(--radius-md, 8px);
  transition: background-color var(--duration-fast) var(--ease-out),
              color var(--duration-fast) var(--ease-out);
  text-decoration: none;
  white-space: nowrap;
}

.header-nav .nav-submenu a:hover {
  background-color: var(--color-gray-100, #f5f5f5);
  color: var(--color-primary);
}

/* Hide legacy hamburger entirely (replaced by .header-menu-btn) */
.hamburger {
  display: none !important;
}

/* ========== Fullscreen menu overlay (mobile / small screens) ========== */
.menu-overlay {
  position: fixed;
  inset: 0;
  background-color: var(--color-white);
  z-index: var(--z-overlay);
  opacity: 0;
  visibility: hidden;
  transition: all var(--duration-slow) var(--ease-out);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-20) var(--space-6);
  overflow-y: auto;
}

.menu-overlay.is-open {
  opacity: 1;
  visibility: visible;
}

.menu-overlay-nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  width: 100%;
  max-width: 520px;
}

.menu-overlay-link,
.menu-overlay-parent {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--space-3) 0;
  font-family: var(--font-en);
  font-size: var(--text-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-dark);
  background: none;
  border: none;
  border-bottom: 1px solid var(--color-gray-200);
  text-align: left;
  cursor: pointer;
  transition: color var(--duration-fast) var(--ease-out);
}

.menu-overlay-link:hover,
.menu-overlay-parent:hover {
  color: var(--color-primary);
}

.menu-overlay-parent-icon {
  position: relative;
  display: inline-block;
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.menu-overlay-parent-icon::before,
.menu-overlay-parent-icon::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  background-color: currentColor;
  transition: transform var(--duration-fast) var(--ease-out);
}

.menu-overlay-parent-icon::before {
  width: 16px;
  height: 2px;
  transform: translate(-50%, -50%);
}

.menu-overlay-parent-icon::after {
  width: 2px;
  height: 16px;
  transform: translate(-50%, -50%);
}

.menu-overlay-parent[aria-expanded="true"] .menu-overlay-parent-icon::after {
  transform: translate(-50%, -50%) scaleY(0);
}

.menu-overlay-sub {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--duration-normal) var(--ease-out);
  display: flex;
  flex-direction: column;
}

.menu-overlay-parent[aria-expanded="true"] + .menu-overlay-sub {
  max-height: 600px;
}

.menu-overlay-sub a {
  display: block;
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-ja);
  font-size: var(--text-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-600, #555);
  border-bottom: 1px solid var(--color-gray-100, #f0f0f0);
  transition: color var(--duration-fast) var(--ease-out);
}

.menu-overlay-sub a:hover {
  color: var(--color-primary);
}

/* ========== BUTTONS ========== */
.btn-more {
  display: inline-flex;
  align-items: center;
  gap: var(--space-4);
  padding: 0;
  background: none;
  border: none;
  color: var(--color-dark);
  font-family: var(--font-ja);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  transition: opacity var(--duration-fast) var(--ease-out);
}

.btn-more:hover {
  opacity: 0.7;
}

.btn-more::after {
  content: '→';
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border: 1px solid var(--color-gray-300);
  border-radius: 50%;
  font-family: var(--font-en);
  font-size: var(--text-base);
  color: var(--color-primary);
  transition: all var(--duration-normal) var(--ease-out);
}

.btn-more:hover::after {
  background-color: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
  transform: translateX(4px);
}

/* Circle CTA button - icon on left, text on right */
.btn-circle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-4);
  background: none;
  border: none;
  color: var(--color-dark);
  font-family: var(--font-ja);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  transition: opacity var(--duration-fast) var(--ease-out);
}

.btn-circle:hover {
  opacity: 0.75;
}

.btn-circle-arrow {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 64px;
  height: 64px;
  border: 1px solid var(--color-gray-300);
  border-radius: 50%;
  font-family: var(--font-en);
  font-size: var(--text-lg);
  color: var(--color-primary);
  transition: all var(--duration-normal) var(--ease-out);
}

.btn-circle:hover .btn-circle-arrow {
  background-color: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
  transform: translateX(4px);
}

/* Contact button on header (legacy fallback) */
.btn-contact {
  display: inline-block;
  font-family: var(--font-en);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  letter-spacing: var(--tracking-wide);
  color: var(--color-white);
  background-color: var(--color-primary);
  padding: 14px var(--space-8);
  border-radius: var(--radius-full);
  transition: all var(--duration-normal) var(--ease-out);
}

.btn-contact:hover {
  background-color: var(--color-primary-dark);
  box-shadow: var(--shadow-lg);
}