:root {
  --color-bg: rgba(255, 255, 255, 0.92);
  --color-border: #dbeafe;
  --color-accent: #2563eb;
  --color-accent-2: #3b82f6;
  --color-text: #0f172a;
  --color-muted: #64748b;
  --radius: 14px;
  --transition: all 0.25s ease;
  --shadow: 0 10px 26px rgba(37, 99, 235, 0.12);
}

/* ====== CABECERA PRINCIPAL ====== */
.topbar {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px) saturate(180%);
  -webkit-backdrop-filter: blur(12px) saturate(180%);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow);
}

.topbar__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 7px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

/* ====== LOGO ====== */
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.brand__logo {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  object-fit: contain;
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid var(--color-border);
}

.brand__name {
  font-weight: 700;
  font-size: 18px;
  color: var(--color-text);
  letter-spacing: 0.3px;
}

/* ====== NAVEGACIÓN ====== */
.nav {
  display: flex;
}

.nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav__item {
  position: relative;
}

.nav__link {
  display: inline-block;
  padding: 10px 16px;
  border-radius: var(--radius);
  color: var(--color-text);
  text-decoration: none;
  transition: var(--transition);
  font-weight: 500;
}

.nav__link:hover {
  background: #eff6ff;
  color: var(--color-accent);
  transform: translateY(-1px);
}

.nav__link.is-active {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-2) 100%);
  color: #fff;
  box-shadow: 0 10px 18px rgba(37, 99, 235, 0.22);
}

.nav__submenu {
  list-style: none;
  margin: 0;
  padding: 8px;
  min-width: 220px;
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  background: #fff;
  border: 1px solid #bfdbfe;
  border-radius: 12px;
  box-shadow: var(--shadow);
  display: none;
  z-index: 120;
}

.nav__item--dropdown:hover .nav__submenu {
  display: block;
}

.nav__sublink {
  display: block;
  padding: 9px 10px;
  border-radius: 10px;
  text-decoration: none;
  color: var(--color-text);
  font-size: 14px;
  transition: var(--transition);
}

.nav__sublink:hover {
  background: #eff6ff;
  color: var(--color-accent);
}

/* ====== BOTÓN HAMBURGUESA ====== */
.nav-toggle {
  display: none;
  background: #ffffff;
  border: 1px solid #bfdbfe;
  border-radius: var(--radius);
  width: 42px;
  height: 42px;
  cursor: pointer;
  font-size: 22px;
  color: var(--color-text);
  transition: var(--transition);
}

.nav-toggle:hover {
  background: #eff6ff;
  color: var(--color-accent);
  transform: translateY(-1px);
}

/* ====== RESPONSIVE ====== */
@media (max-width: 820px) {
  .nav-toggle {
    display: block;
  }

  .nav {
    position: absolute;
    right: 16px;
    top: 70px;
    display: none;
    flex-direction: column;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid #bfdbfe;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 10px;
  }

  .nav.is-open {
    display: flex;
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    min-width: 200px;
  }

  .nav__link {
    text-align: left;
    font-size: 15px;
  }

  .nav__submenu {
    position: static;
    display: block;
    margin-top: 4px;
    padding: 4px;
    box-shadow: none;
    border: 1px dashed #bfdbfe;
  }
}

/* ====== ANIMACIÓN SUTIL ====== */
@media (prefers-reduced-motion: no-preference) {
  .topbar__inner,
  .nav__link,
  .nav-toggle {
    transition: var(--transition);
  }
}