/* ==========================================================================
   AIRH App Shell Layout — CSS Grid
   ========================================================================== */

/* ---------------------------------------------------------------------------
   App Layout Container
   --------------------------------------------------------------------------- */
.app-layout {
  min-height: 100vh;
  min-height: 100dvh;
  width: 100%;
}

/* Main content offset by fixed sidebar */
.app-layout > .main-content {
  margin-left: var(--sidebar-width);
  transition: margin-left var(--transition-panel);
}

/* Sidebar collapsed state */
.app-layout.sidebar-collapsed > .main-content {
  margin-left: var(--sidebar-collapsed);
}

/* ---------------------------------------------------------------------------
   Main Content Area
   --------------------------------------------------------------------------- */
.main-content {
  display: grid;
  grid-template-rows: var(--topbar-height) 1fr;
  min-height: 100vh;
  min-height: 100dvh;
  overflow: hidden;
}

/* ---------------------------------------------------------------------------
   Content Scrollable Area
   --------------------------------------------------------------------------- */
.content-area {
  overflow-y: auto;
  overflow-x: hidden;
  padding: var(--space-8);
  background-color: var(--color-bg-secondary);
}

.content-area--flush {
  padding: 0;
}

/* ---------------------------------------------------------------------------
   Page Container
   --------------------------------------------------------------------------- */
.page-container {
  width: 100%;
  max-width: var(--content-max-width);
  margin: 0 auto;
}

.page-container--narrow {
  max-width: var(--form-max-width);
}

.page-container--wide {
  max-width: 100%;
}

/* ---------------------------------------------------------------------------
   Page Header
   --------------------------------------------------------------------------- */
.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  margin-bottom: var(--space-8);
  flex-wrap: wrap;
}

.page-header__title-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.page-header__title {
  font-size: var(--text-2xl);
  font-weight: var(--weight-bold);
  color: var(--color-text-primary);
  letter-spacing: var(--tracking-tight);
}

.page-header__subtitle {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.page-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

/* ---------------------------------------------------------------------------
   Section
   --------------------------------------------------------------------------- */
.section {
  margin-bottom: var(--space-8);
}

.section__title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  color: var(--color-text-primary);
  margin-bottom: var(--space-5);
}

.section__description {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-5);
}

/* ---------------------------------------------------------------------------
   Grid Systems
   --------------------------------------------------------------------------- */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid--2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid--3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid--4 {
  grid-template-columns: repeat(4, 1fr);
}

.grid--auto-fill {
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
}

.grid--auto-fit {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

/* ---------------------------------------------------------------------------
   Responsive — Tablet (< 1024px)
   --------------------------------------------------------------------------- */
@media (max-width: 1023px) {
  .app-layout > .main-content {
    margin-left: 0;
  }

  .app-layout.sidebar-collapsed > .main-content {
    margin-left: 0;
  }

  .main-content {
    grid-template-rows: var(--topbar-height) 1fr var(--bottom-nav-height);
  }

  .content-area {
    padding: var(--space-6) var(--space-4);
    padding-bottom: calc(var(--space-6) + var(--bottom-nav-height));
  }

  .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid--3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ---------------------------------------------------------------------------
   Responsive — Mobile (< 640px)
   --------------------------------------------------------------------------- */
@media (max-width: 639px) {
  .content-area {
    padding: var(--space-4) var(--space-4);
    padding-bottom: calc(var(--space-4) + var(--bottom-nav-height));
  }

  .page-header {
    flex-direction: column;
    gap: var(--space-3);
    margin-bottom: var(--space-6);
  }

  .page-header__actions {
    width: 100%;
  }

  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: 1fr;
  }

  .grid--auto-fill,
  .grid--auto-fit {
    grid-template-columns: 1fr;
  }
}