/* Shared app shell — left navigation + main content */
.app-shell {
  display: flex;
  min-height: 100vh;
  position: relative;
}

.side-nav {
  width: 220px;
  flex-shrink: 0;
  background: #1a2332;
  border-right: 1px solid #334155;
  display: flex;
  flex-direction: column;
  transition: width 0.2s ease, margin 0.2s ease, opacity 0.2s ease;
  overflow: hidden;
}

.app-shell.side-nav-collapsed .side-nav {
  width: 0;
  border-right-width: 0;
  opacity: 0;
  pointer-events: none;
}

.side-nav-toggle {
  position: absolute;
  left: 220px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 20;
  width: 18px;
  height: 52px;
  padding: 0;
  border: 1px solid #475569;
  border-left: none;
  border-radius: 0 6px 6px 0;
  background: #1e293b;
  color: #cbd5e1;
  font-size: 11px;
  line-height: 1;
  cursor: pointer;
  transition: left 0.2s ease, background 0.15s ease;
}

.side-nav-toggle:hover {
  background: #334155;
  color: #fff;
}

.app-shell.side-nav-collapsed .side-nav-toggle {
  left: 0;
  border-left: 1px solid #475569;
  border-radius: 0 6px 6px 0;
}

.side-nav-toggle:focus-visible {
  outline: 2px solid #38bdf8;
  outline-offset: 1px;
}

.side-nav-brand {
  padding: 1rem 1rem 0.75rem;
  border-bottom: 1px solid #334155;
}

.side-nav-brand h2 {
  margin: 0;
  font-size: 1rem;
  color: #f1f5f9;
}

.side-nav-brand p {
  margin: 0.25rem 0 0;
  font-size: 0.72rem;
  color: #94a3b8;
}

.side-nav-site {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid #334155;
}

.side-nav-site label {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: #cbd5e1;
}

.side-nav-site select {
  font: inherit;
  font-size: 0.8rem;
  padding: 0.4rem 0.5rem;
  border: 1px solid #475569;
  border-radius: 4px;
  background: #0f172a;
  color: #f1f5f9;
}

.side-nav-menu {
  flex: 1;
  padding: 0.5rem 0;
  overflow-y: auto;
}

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

.nav-group-title {
  display: block;
  padding: 0.5rem 1rem 0.25rem;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #64748b;
}

.nav-link {
  display: block;
  padding: 0.45rem 1rem 0.45rem 1.25rem;
  font-size: 0.85rem;
  color: #cbd5e1;
  text-decoration: none;
  border-left: 3px solid transparent;
}

.nav-link:hover {
  background: #243044;
  color: #fff;
}

.nav-link.active {
  background: #2d3a52;
  color: #38bdf8;
  border-left-color: #38bdf8;
  font-weight: 600;
}

.nav-link.sub {
  padding-left: 1.75rem;
  font-size: 0.82rem;
}

.side-nav-footer {
  padding: 0.75rem 1rem;
  border-top: 1px solid #334155;
  font-size: 0.72rem;
}

.side-nav-footer a {
  color: #94a3b8;
  text-decoration: none;
}

.side-nav-footer a:hover {
  color: #38bdf8;
}

.app-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.app-main > header.compact-header {
  padding: 0.75rem 1.25rem;
  background: linear-gradient(135deg, #1e3a5f, #312e81);
  border-bottom: 1px solid #334155;
}

.app-main > header.compact-header h1 {
  margin: 0;
  font-size: 1.15rem;
}

.app-main > header.compact-header .tagline {
  margin: 0.2rem 0 0;
  font-size: 0.8rem;
  color: #cbd5e1;
}

.app-main > .tabs {
  padding-left: 1.25rem;
}

.app-main > main {
  max-width: none;
  flex: 1;
}

@media (max-width: 900px) {
  .app-shell {
    flex-direction: column;
  }
  .side-nav {
    width: 100%;
    max-height: none;
    opacity: 1;
    pointer-events: auto;
  }
  .app-shell.side-nav-collapsed .side-nav {
    display: none;
  }
  .side-nav-toggle {
    left: auto;
    right: 0.5rem;
    top: 0.5rem;
    transform: none;
    height: 32px;
    width: 32px;
    border-radius: 6px;
    border: 1px solid #475569;
  }
  .app-shell.side-nav-collapsed .side-nav-toggle {
    left: auto;
    right: 0.5rem;
  }
  .side-nav-menu {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
    padding: 0.5rem;
  }
  .nav-group-title { display: none; }
  .nav-link { border-left: none; border-radius: 4px; padding: 0.4rem 0.65rem; }
  .nav-link.sub { padding-left: 0.65rem; }
}