.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 70;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(7, 8, 10, 0.62);
  backdrop-filter: blur(18px);
  transition: background 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.site-header.scrolled {
  border-color: rgba(0, 0, 0, 0.08);
  background: rgba(7, 8, 10, 0.92);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.18);
}

.nav {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: #fff;
  font-weight: 950;
  letter-spacing: -0.02em;
}

.brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 78px;
  height: 48px;
  overflow: visible;
  border-radius: 0;
  background: transparent;
}

.brand__mark img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.brand__text {
  white-space: nowrap;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 22px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 0.94rem;
  font-weight: 800;
}

.nav-menu a:not(.btn):hover {
  color: #fff;
}

.nav-toggle {
  display: none;
  width: 46px;
  height: 46px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px auto;
  border-radius: 999px;
  background: currentColor;
}

@media (max-width: 920px) {
  .nav {
    min-height: 68px;
  }

  .brand__mark {
    width: 68px;
    height: 42px;
  }

  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    left: 16px;
    right: 16px;
    top: 78px;
    display: grid;
    gap: 2px;
    padding: 16px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 18px;
    background: rgba(7, 8, 10, 0.98);
    box-shadow: var(--dcm-shadow);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-12px);
    transition: opacity 0.2s ease, transform 0.2s ease;
  }

  .nav-menu.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav-menu a {
    padding: 14px;
    border-radius: 12px;
  }

  .nav-menu .btn {
    margin-top: 8px;
  }
}