/* ============================================
   导航栏样式 - Blueprint 工控导航
   ============================================ */

.navbar {
  position: fixed;
  inset: 0 0 auto 0;
  background: linear-gradient(90deg, rgba(13, 29, 50, 0.95), rgba(12, 24, 41, 0.95));
  border-bottom: 1px solid rgba(124, 199, 255, 0.25);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  z-index: 1000;
  padding: 0 var(--spacing-lg);
  backdrop-filter: blur(10px);
}

.navbar::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, #7cc7ff, transparent);
  opacity: 0.9;
}

.navbar-content {
  max-width: var(--container-max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 78px;
}

.navbar-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  color: #E8EDF1;
  font-weight: 800;
  font-size: var(--font-size-lg);
  letter-spacing: 0.4px;
}

.navbar-logo-icon {
  width: 46px; height: 46px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, #7cc7ff, #3d6a99);
  color: #0D1A1F;
  border-radius: 12px;
  font-weight: 800;
  box-shadow: 0 8px 22px rgba(124, 199, 255, 0.45);
}

.navbar-menu { display: flex; list-style: none; margin: 0; padding: 0; }
.navbar-item { position: relative; }

.navbar-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-lg) var(--spacing-xl);
  color: rgba(232, 237, 241, 0.82);
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--transition-fast), background var(--transition-fast);
}

.navbar-link:hover { color: white; }

.navbar-link.active {
  color: white;
  background: linear-gradient(180deg, rgba(124, 199, 255, 0.12), transparent);
  border-bottom: 2px solid #7cc7ff;
}

.navbar-arrow { font-size: 12px; transition: transform var(--transition-fast); }
.navbar-item:hover .navbar-arrow { transform: rotate(180deg); }

.navbar-submenu {
  position: absolute;
  top: 100%; left: 0;
  min-width: 230px;
  background: #0f1d30;
  border: 1px solid rgba(124, 199, 255, 0.25);
  border-radius: var(--radius-lg);
  list-style: none;
  padding: var(--spacing-sm) 0;
  margin: 0;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.35);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-base);
  z-index: 10;
  backdrop-filter: blur(8px);
}

.navbar-item:hover .navbar-submenu { opacity: 1; visibility: visible; transform: translateY(0); }

.navbar-submenu-item { border-bottom: 1px solid rgba(124, 199, 255, 0.12); }
.navbar-submenu-item:last-child { border-bottom: none; }

.navbar-submenu-link {
  display: block;
  padding: var(--spacing-md) var(--spacing-xl);
  color: rgba(232, 237, 241, 0.82);
  font-weight: 500;
  transition: all var(--transition-fast);
}

.navbar-submenu-link:hover {
  background: rgba(124, 199, 255, 0.12);
  color: white;
  padding-left: calc(var(--spacing-xl) + 6px);
}

.navbar-toggle {
  display: none;
  background: none;
  border: 1px solid rgba(232, 237, 241, 0.16);
  border-radius: var(--radius-md);
  padding: var(--spacing-sm);
  cursor: pointer;
}

.navbar-toggle-icon { width: 24px; height: 24px; display: grid; gap: 4px; }
.navbar-toggle-icon span { display: block; height: 2px; background: white; border-radius: 2px; }

@media (max-width: 900px) {
  .navbar-toggle { display: block; }
  .navbar-menu {
    position: absolute;
    top: 78px; left: 0; right: 0;
    flex-direction: column;
    background: #0f1d30;
    border-bottom: 1px solid rgba(124, 199, 255, 0.18);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
  }
  .navbar.active .navbar-menu { max-height: 720px; }
  .navbar-item { border-bottom: 1px solid rgba(124, 199, 255, 0.12); }
  .navbar-link { padding: var(--spacing-lg) var(--spacing-xl); }
  .navbar-link.active { background: rgba(124, 199, 255, 0.12); border-bottom: none; }
  .navbar-submenu {
    position: static;
    transform: none;
    opacity: 0;
    visibility: hidden;
    max-height: 0;
    border: none;
    border-top: 1px solid rgba(124, 199, 255, 0.12);
    border-radius: 0;
    box-shadow: none;
  }
  .navbar-item.active .navbar-submenu { opacity: 1; visibility: visible; max-height: 560px; }
}

@media (max-width: 480px) {
  .navbar-content { height: 64px; padding: 0 var(--spacing-md); }
  .navbar-logo { font-size: var(--font-size-base); }
  .navbar-logo-icon { width: 38px; height: 38px; }
  .navbar-link { padding: var(--spacing-md) var(--spacing-lg); font-size: var(--font-size-sm); }
  .navbar-submenu-link { padding: var(--spacing-sm) var(--spacing-lg); }
}

/* 页面内容需要 top padding 来避免被导航栏覆盖 */
body { padding-top: 78px; }
@media (max-width: 900px) { body { padding-top: 66px; } }
@media (max-width: 480px) { body { padding-top: 60px; } }