.site-header {
  position: fixed;
  top: 0;
  inset-inline: 0;
  height: var(--header-h);
  z-index: 100;
  transition: background var(--dur-mid), border-color var(--dur-mid);
}


.site-header.is-home {
  background: transparent;
  border-bottom: 2px solid transparent;
}


.site-header:not(.is-home) {
  background: var(--c-bg);
  border-bottom: 2px solid var(--c-ink);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}


.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--c-ink);
  min-height: 44px;
  flex-shrink: 0;
}
.logo:hover {
  text-decoration: none;
  color: var(--c-ink);
}
.logo .logo-toho {
  color: var(--c-ink);
}
.logo .logo-viro {
  color: var(--c-blue);
}
.logo svg {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}


.desktop-nav {
  display: none;
}
@media (min-width: 861px) {
  .desktop-nav {
    display: flex;
  }
}

.desktop-nav ul {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.desktop-nav a {
  display: inline-flex;
  align-items: center;
  height: 44px;
  padding-inline: 14px;
  font-family: var(--font-display);
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--c-ink);
  text-decoration: none;
  border-radius: var(--r-sm);
  transition: background var(--dur-fast), color var(--dur-fast);
  white-space: nowrap;
}
.desktop-nav a:hover {
  background: var(--c-blue-tint);
  color: var(--c-blue-dark);
}
.desktop-nav a[aria-current="page"] {
  background: var(--c-sun);
  color: var(--c-ink);
  box-shadow: 2px 2px 0 var(--c-ink);
}


.hamburger {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: var(--r-sm);
  color: var(--c-ink);
  transition: background var(--dur-fast);
}
.hamburger:hover {
  background: var(--c-blue-tint);
}
@media (min-width: 861px) {
  .hamburger {
    display: none;
  }
}

.hamburger-icon,
.hamburger-icon::before,
.hamburger-icon::after {
  display: block;
  width: 22px;
  height: 2.5px;
  background: var(--c-ink);
  border-radius: var(--r-pill);
  transition: transform var(--dur-fast) var(--ease-out), opacity var(--dur-fast);
}
.hamburger-icon {
  position: relative;
}
.hamburger-icon::before,
.hamburger-icon::after {
  content: '';
  position: absolute;
  left: 0;
}
.hamburger-icon::before {
  top: -7px;
}
.hamburger-icon::after {
  top: 7px;
}


.hamburger[aria-expanded="true"] .hamburger-icon {
  background: transparent;
}
.hamburger[aria-expanded="true"] .hamburger-icon::before {
  transform: translateY(7px) rotate(45deg);
}
.hamburger[aria-expanded="true"] .hamburger-icon::after {
  transform: translateY(-7px) rotate(-45deg);
}


.mobile-nav-panel {
  position: fixed;
  inset: 0;
  background: var(--c-bg);
  z-index: 99;
  display: flex;
  flex-direction: column;
  visibility: hidden;
  opacity: 0;
  transition: opacity var(--dur-mid) var(--ease-out), visibility 0s var(--dur-mid);
  overflow-y: auto;
}
.mobile-nav-panel.is-open {
  visibility: visible;
  opacity: 1;
  transition: opacity var(--dur-mid) var(--ease-out), visibility 0s;
}
@media (min-width: 861px) {
  .mobile-nav-panel {
    display: none !important;
  }
}

.mobile-nav-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100%;
  padding: 80px var(--gutter) 40px;
  gap: 12px;
}

.mobile-nav-close {
  position: absolute;
  top: 12px;
  right: 16px;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--c-ink-soft);
  border-radius: var(--r-sm);
  transition: background var(--dur-fast), color var(--dur-fast);
}
.mobile-nav-close:hover {
  background: var(--c-line);
  color: var(--c-ink);
}

.mobile-nav-panel a {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
  padding-inline: 32px;
  width: 100%;
  max-width: 320px;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 6vw, 2.2rem);
  font-weight: 800;
  color: var(--c-ink);
  text-decoration: none;
  border-radius: var(--r-md);
  text-align: center;
  transition: background var(--dur-fast), color var(--dur-fast);
}
.mobile-nav-panel a:hover,
.mobile-nav-panel a:focus-visible {
  background: var(--c-blue-tint);
  color: var(--c-blue);
}
.mobile-nav-panel a[aria-current="page"] {
  background: var(--c-sun);
  color: var(--c-ink);
  box-shadow: 3px 3px 0 var(--c-ink);
}