.dia-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 1000;
  height: var(--dia-header-height);
  background: rgba(32, 39, 40, 0);
  transition:
    background-color 0.32s ease,
    backdrop-filter 0.32s ease,
    box-shadow 0.32s ease;
}

.dia-header.is-scrolled {
  background: rgba(32, 39, 40, 0.74);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.14);
}

.dia-header-inner {
  height: var(--dia-header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.dia-header-logo-link {
  display: inline-flex;
  align-items: center;
  width: 92px;
  min-width: 92px;
  text-decoration: none;
}

.dia-header-logo {
  width: 92px;
  height: auto;
  opacity: 0.94;
  transition: opacity 0.28s ease, transform 0.28s ease;
}

.dia-header-logo-link:hover .dia-header-logo {
  opacity: 1;
  transform: translateY(-1px);
}

.dia-header-nav {
  display: flex;
  align-items: center;
  gap: 30px;
}

.dia-header-nav a {
  position: relative;
  font-family: var(--dia-font-ui);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  text-decoration: none;
  color: rgba(255, 255, 255, 0.9);
}

.dia-header-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -8px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.25s ease;
}

.dia-header-nav a:hover::after,
.dia-header-nav a:focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}

@media (max-width: 640px) {
  :root {
    --dia-header-height: 76px;
  }

  .dia-container {
    width: min(calc(100% - 32px), var(--dia-container));
  }

  .dia-header-logo-link,
  .dia-header-logo {
    width: 76px;
    min-width: 76px;
  }

  .dia-header-nav {
    gap: 18px;
  }

  .dia-header-nav a {
    font-size: 0.64rem;
    letter-spacing: 0.17em;
  }
}