/* ===========================================================
   Vertx Pharmaceuticals — Shared Site Navigation
   Included on every page via <link rel="stylesheet" href="nav.css">
   Namespaced with "vtx-" prefixes so it never collides with
   each page's own local styles (e.g. existing .nav-container
   divison filters on the product pages).
   =========================================================== */

:root {
  --vtx-primary: #005eb8;
  --vtx-primary-dark: #004a8f;
  --vtx-secondary: #00a9e0;
  --vtx-dark: #1a1a2e;
  --vtx-white: #ffffff;
  --vtx-text: #23262f;
  --vtx-border: #eef0f3;
  --vtx-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
}

.vtx-nav {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(10px);
  z-index: 2000;
  box-shadow: var(--vtx-shadow);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

.vtx-nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0.85rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.vtx-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--vtx-primary);
  text-decoration: none;
  white-space: nowrap;
}

.vtx-logo-icon {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--vtx-primary), var(--vtx-secondary));
  color: var(--vtx-white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1rem;
  flex-shrink: 0;
}

.vtx-nav-links {
  display: flex;
  align-items: center;
  gap: 1.6rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.vtx-nav-links > li {
  position: relative;
}

.vtx-nav-links > li > a {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  text-decoration: none;
  color: var(--vtx-text);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 0;
  transition: color 0.2s ease;
  cursor: pointer;
}

.vtx-nav-links > li > a:hover,
.vtx-nav-links > li > a.vtx-active {
  color: var(--vtx-primary);
}

.vtx-caret {
  font-size: 0.65rem;
  transition: transform 0.2s ease;
  margin-top: 2px;
}

.vtx-dropdown:hover .vtx-caret,
.vtx-dropdown.vtx-open .vtx-caret {
  transform: rotate(180deg);
}

.vtx-dropdown-menu {
  list-style: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 250px;
  background: var(--vtx-white);
  border-radius: 10px;
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.14);
  padding: 0.5rem;
  margin: 0.5rem 0 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease;
}

.vtx-dropdown:hover .vtx-dropdown-menu,
.vtx-dropdown.vtx-open .vtx-dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.vtx-dropdown-menu li a {
  display: block;
  padding: 0.65rem 0.85rem;
  border-radius: 6px;
  color: var(--vtx-text);
  text-decoration: none;
  font-size: 0.9rem;
  white-space: nowrap;
}

.vtx-dropdown-menu li a:hover,
.vtx-dropdown-menu li a.vtx-active {
  background: #eef6fd;
  color: var(--vtx-primary);
}

.vtx-mobile-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--vtx-primary);
  cursor: pointer;
  line-height: 1;
}

@media (max-width: 860px) {
  .vtx-nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--vtx-white);
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.25rem 1.25rem 1rem;
    box-shadow: 0 14px 34px rgba(0, 0, 0, 0.14);
    max-height: 80vh;
    overflow-y: auto;
  }

  .vtx-nav-links.vtx-mobile-open {
    display: flex;
  }

  .vtx-nav-links > li {
    width: 100%;
  }

  .vtx-nav-links > li > a {
    padding: 0.85rem 0.1rem;
    justify-content: space-between;
    border-bottom: 1px solid var(--vtx-border);
  }

  .vtx-dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    display: none;
    margin: 0;
    padding: 0 0 0 1rem;
  }

  .vtx-dropdown.vtx-open .vtx-dropdown-menu {
    display: block;
  }

  .vtx-mobile-btn {
    display: block;
  }
}