.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;

  background: rgba(10, 10, 10, 0.55);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);

  border-bottom: 1px solid rgba(255,255,255,0.06);

  transition: transform 0.35s ease, background 0.25s ease;
}

.header.hidden {
  transform: translateY(-100%);
}

.header-content {
  min-height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* LOGO */
.logo {
  display: flex;
  align-items: center;
}

.main-logo-img {
  filter: invert(1);
  height: 38px;
  width: auto;
  object-fit: contain;
  mix-blend-mode: screen;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.main-logo-img:hover {
  transform: scale(1.04);
  opacity: 0.9;
}

/* NAV WRAPPER */
.nav-and-selector-wrapper {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex: 1;
  gap: 22px;
  min-width: 0;
}

/* NAV */
.main-nav {
  display: flex;
  align-items: center;
  gap: 18px;

  padding: 0;
  border-radius: 0;

  background: transparent;
  border: none;
}

.nav-link {
  position: relative;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  color: rgba(255,255,255,0.65);
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: #fff;
}

/* clean underline (no card feel) */
.nav-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -6px;

  width: 0%;
  height: 2px;
  border-radius: 999px;

  background: #3b82f6;

  transition: width 0.25s ease;
}

.nav-link:hover::after {
  width: 100%;
}

.nav-link.active {
  color: #fff;
}

.nav-link.active::after {
  width: 100%;
}

/* SITE SLIDER */
.site-slider {
  display: flex;
  align-items: center;
  gap: 16px;

  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;

  padding: 4px 6px;
  max-width: 620px;
}

.site-slider::-webkit-scrollbar {
  display: none;
}

.site-slider-item {
  display: flex;
  align-items: center;
  gap: 10px;

  flex-shrink: 0;
  cursor: pointer;

  opacity: 0.65;

  transition: transform 0.2s ease, opacity 0.2s ease;
}

.site-slider-item:hover {
  opacity: 1;
  transform: translateY(-1px);
}

.site-slider-item img {
  width: 30px;
  height: 30px;

  object-fit: cover;
  border-radius: 50%;
}

.site-slider-item span {
  font-size: 0.8rem;
  font-weight: 600;
  color: rgba(255,255,255,0.7);

  white-space: nowrap;
}

.site-slider-item.active {
  opacity: 1;
}

.site-slider-item.active img {
  box-shadow: 0 0 0 2px rgba(59,130,246,0.35);
}

/* RESPONSIVE */
body {
  padding-top: 80px;
}

@media (max-width: 900px) {
  .main-nav {
    display: none;
  }

  .nav-and-selector-wrapper {
    justify-content: flex-end;
  }

  .site-slider {
    max-width: 100%;
  }
}

@media (max-width: 768px) {
  .header-content {
    min-height: 64px;
    gap: 14px;
  }

  .main-logo-img {
    height: 32px;
  }

  .site-slider {
    gap: 12px;
  }

  .site-slider-item img {
    width: 26px;
    height: 26px;
  }

  body {
    padding-top: 74px;
  }
}

@media (max-width: 480px) {
  .header-content {
    min-height: 58px;
  }

  .main-logo-img {
    height: 28px;
  }

  .site-slider-item span {
    font-size: 0.7rem;
  }

  body {
    padding-top: 68px;
  }
}