/* Navigation Sidebar */
.app-nav {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.app-brand {
  padding: 1.5rem 1rem;
  border-bottom: 1px solid var(--border);
}

.brand-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-heading);
  margin: 0;
}

.brand-subtitle {
  font-size: 0.75rem;
  color: var(--text-tertiary);
  margin-top: 0.25rem;
}

/* Navigation Menu */
.nav-menu {
  flex: 1;
  padding: 1rem 0;
  list-style: none;
}

.nav-item {
  margin-bottom: 0.25rem;
}

.nav-link {
  display: flex;
  align-items: center;
  padding: 0.75rem 1rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s ease;
  border-left: 3px solid transparent;
  position: relative;
}

.nav-link:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  text-decoration: none;
}

.nav-link.is-active {
  background-color: var(--primary-light);
  color: var(--primary);
  border-left-color: var(--primary);
  font-weight: 500;
}

.nav-icon {
  width: 20px;
  height: 20px;
  margin-right: 0.75rem;
  flex-shrink: 0;
}

.nav-text {
  flex: 1;
}

/* Navigation Footer */
.nav-footer {
  margin-top: auto;
  padding: 1rem;
  border-top: 1px solid var(--border);
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0.5rem 0.75rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 0.875rem;
}

.theme-toggle:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
}

.theme-icon {
  width: 18px;
  height: 18px;
}

/* Mobile Styles */
@media (max-width: 768px) {
  .nav-link {
    padding: 1rem 1.5rem;
  }
}

.nav-logout {
  margin-top: 0.5rem;
  color: var(--text-tertiary);
}

@media (min-width: 1025px) {
  .nav-panel.is-collapsed .app-brand {
    display: none;
  }

  .nav-panel.is-collapsed .nav-menu {
    padding: 0.75rem 0;
  }

  .nav-panel.is-collapsed .nav-footer {
    padding: 0.75rem;
  }

  .nav-panel.is-collapsed .nav-link {
    justify-content: center;
    margin: 0 0.625rem;
    padding: 0.75rem 0;
    border-left-color: transparent;
    border-radius: 12px;
  }

  .nav-panel.is-collapsed .nav-link.is-active {
    border-left-color: transparent;
    box-shadow: inset 3px 0 0 var(--primary);
  }

  .nav-panel.is-collapsed .nav-icon {
    margin-right: 0;
  }

  .nav-panel.is-collapsed .nav-text {
    display: none;
  }

  .nav-panel.is-collapsed .theme-toggle {
    width: 44px;
    height: 44px;
    padding: 0;
    justify-content: center;
    margin: 0 auto;
  }

  .nav-panel.is-collapsed .theme-toggle span {
    display: none;
  }

  .nav-panel.is-collapsed .nav-link::before,
  .nav-panel.is-collapsed .nav-link::after,
  .nav-panel.is-collapsed .theme-toggle::before,
  .nav-panel.is-collapsed .theme-toggle::after {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.18s ease, transform 0.18s ease;
    position: absolute;
  }

  .nav-panel.is-collapsed .nav-link::before,
  .nav-panel.is-collapsed .theme-toggle::before {
    content: '';
    top: 50%;
    left: calc(100% + 12px);
    width: 10px;
    height: 10px;
    background: var(--bg-primary);
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    transform: translateY(-50%) rotate(45deg);
    z-index: 9;
  }

  .nav-panel.is-collapsed .nav-link::after,
  .nav-panel.is-collapsed .theme-toggle::after {
    content: attr(data-nav-label);
    top: 50%;
    left: calc(100% + 16px);
    transform: translateY(-50%) translateX(-4px);
    padding: 0.5rem 0.75rem;
    border-radius: 10px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    color: var(--text-primary);
    font-size: 0.8125rem;
    font-weight: 600;
    white-space: nowrap;
    z-index: 10;
  }

  .nav-panel.is-collapsed .nav-link:hover::before,
  .nav-panel.is-collapsed .nav-link:hover::after,
  .nav-panel.is-collapsed .nav-link:focus-visible::before,
  .nav-panel.is-collapsed .nav-link:focus-visible::after,
  .nav-panel.is-collapsed .theme-toggle:hover::before,
  .nav-panel.is-collapsed .theme-toggle:hover::after,
  .nav-panel.is-collapsed .theme-toggle:focus-visible::before,
  .nav-panel.is-collapsed .theme-toggle:focus-visible::after {
    opacity: 1;
  }

  .nav-panel.is-collapsed .nav-link:hover::after,
  .nav-panel.is-collapsed .nav-link:focus-visible::after,
  .nav-panel.is-collapsed .theme-toggle:hover::after,
  .nav-panel.is-collapsed .theme-toggle:focus-visible::after {
    transform: translateY(-50%) translateX(0);
  }
}