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

.app-header {
  grid-area: header;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-md);
  padding: 0 var(--spacing-lg);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 30;
}

.app-header .brand-mobile {
  display: none;
  font-weight: 600;
  color: var(--color-text-primary);
}

.header-search {
  max-width: 360px;
  width: 100%;
}

.header-user {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: var(--touch-min);
  height: var(--touch-min);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  cursor: pointer;
}

.app-sidebar {
  grid-area: sidebar;
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  padding: var(--spacing-lg) var(--spacing-md);
  position: sticky;
  top: 0;
  height: 100vh;
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 8px 24px;
  color: var(--color-text-primary);
  font-weight: 600;
  font-size: 15px;
}

.sidebar-brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--color-primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 700;
  flex-shrink: 0;
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex: 1;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: var(--touch-min);
  padding: 0 12px;
  border-radius: var(--radius-sm);
  color: var(--color-text-secondary);
  font-weight: 500;
  transition: background var(--transition), color var(--transition);
}

.nav-link svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.nav-link:hover {
  background: var(--color-surface-muted);
  color: var(--color-text-primary);
}

.nav-link.is-active {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}

.sidebar-footer {
  border-top: 1px solid var(--color-border);
  padding-top: var(--spacing-md);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sidebar-user {
  padding: 8px 12px;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.app-main {
  grid-area: main;
  padding: var(--spacing-lg);
  max-width: calc(var(--content-max) + var(--spacing-xl) * 2);
  width: 100%;
}

.sidebar-backdrop {
  display: none;
}

.login-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: var(--spacing-md);
  background:
    radial-gradient(ellipse at top, rgba(101, 33, 55, 0.06), transparent 55%),
    var(--color-background);
}

.login-card {
  width: min(400px, 100%);
  padding: 36px 32px;
}

.login-card .login-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 28px;
  font-weight: 600;
}

.login-card h1 {
  font-size: 26px;
  font-weight: 600;
  margin-bottom: 6px;
}

.login-card .login-sub {
  color: var(--color-text-secondary);
  margin-bottom: 28px;
}

@media (max-width: 1023px) {
  .app-shell {
    grid-template-columns: 1fr;
    grid-template-areas:
      "header"
      "main";
  }

  .app-sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: min(280px, 86vw);
    z-index: 50;
    transform: translateX(-105%);
    transition: transform 200ms ease;
    box-shadow: var(--shadow-md);
  }

  .app-shell.nav-open .app-sidebar {
    transform: translateX(0);
  }

  .sidebar-backdrop {
    display: block;
    position: fixed;
    inset: 0;
    background: rgba(47, 47, 47, 0.35);
    z-index: 40;
    opacity: 0;
    pointer-events: none;
    transition: opacity 200ms ease;
  }

  .app-shell.nav-open .sidebar-backdrop {
    opacity: 1;
    pointer-events: auto;
  }

  .menu-toggle,
  .app-header .brand-mobile {
    display: inline-flex;
  }

  .header-search {
    display: none;
  }

  .app-main {
    padding: var(--spacing-md);
  }
}