:root {
  --sidebar-width: 260px;
}

body {
  background: #f4f7fb;
  min-height: 100vh;
}

.app-shell {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr;
  min-height: 100vh;
}

.app-sidebar {
  background: #0f172a;
  color: #fff;
  padding: 1.2rem 1rem;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.app-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.app-brand img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.app-brand-title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 700;
}

.app-nav .nav-link {
  color: #cbd5e1;
  border-radius: 0.5rem;
  margin-bottom: 0.3rem;
}

.app-nav .nav-link:hover,
.app-nav .nav-link.active {
  color: #fff;
  background: #1d4ed8;
}

.app-main {
  padding: 1rem 1.25rem 2rem;
  overflow-x: auto;
}

.app-header {
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 0.75rem;
  padding: 0.85rem 1rem;
  margin-bottom: 1rem;
}

@media (max-width: 991px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .app-sidebar {
    position: static;
    height: auto;
  }
}