/* ============================================================================
   Page — Layout Skeleton
   BEM block: .page
   Replaces: *-page, *-header, *-layout, *-sidebar, *-main, *-content,
             *-fab, *-sidebar-backdrop per-page patterns
   Mobile-first: single column base, sidebar + content at md (768px)
   ============================================================================ */

/* -- Block ---------------------------------------------------------------- */

.page {
  display: flex;
  flex-direction: column;
  height: calc(100vh - 53px);
  overflow: hidden;
  width: 100%;
  max-width: 100%;
  position: relative;
}

/* -- Header --------------------------------------------------------------- */

.page__header {
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

.page__title {
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  color: var(--color-text);
  margin: 0;
  line-height: 1.2;
}

.page__subtitle {
  font-size: var(--text-sm);
  color: var(--color-muted);
  margin: 0;
}

/* -- Toolbar (below header, above content) -------------------------------- */

.page__toolbar {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

/* -- Layout (sidebar + content wrapper) ----------------------------------- */
/* On mobile: single column, sidebar hidden off-screen                       */

.page__layout {
  display: flex;
  flex: 1;
  overflow: hidden;
  min-height: 0;
  position: relative;
}

/* -- Sidebar -------------------------------------------------------------- */
/* Mobile: fixed drawer, slides in from left                                 */

.page__sidebar {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 260px;
  max-width: 85vw;
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  z-index: var(--z-dropdown);
  transform: translateX(-100%);
  transition: transform 0.25s ease;
  box-shadow: 2px 0 10px rgba(0, 0, 0, 0.3);
}

.page__sidebar.is-open {
  transform: translateX(0);
}

/* -- Content -------------------------------------------------------------- */

.page__content {
  flex: 1;
  min-width: 0;
  overflow-y: auto;
  overflow-x: hidden;
  display: flex;
  flex-direction: column;
}

/* -- Backdrop (mobile sidebar overlay) ------------------------------------ */

.page__backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: calc(var(--z-dropdown) - 1);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.page__backdrop.is-visible {
  display: block;
  opacity: 1;
}

/* -- FAB (floating action button, mobile only) ---------------------------- */

.page__fab {
  display: flex;
  position: absolute;
  bottom: 80px;
  right: 20px;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #fff;
  border: none;
  box-shadow: 0 4px 12px rgba(74, 158, 255, 0.4);
  cursor: pointer;
  z-index: var(--z-base);
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.page__fab:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 16px rgba(74, 158, 255, 0.5);
}

.page__fab:active {
  transform: scale(0.95);
}

/* ============================================================================
   Desktop: sidebar visible inline, FAB + backdrop hidden
   ============================================================================ */

@media (min-width: 768px) {
  .page__sidebar {
    position: static;
    transform: none;
    box-shadow: none;
    max-width: none;
    z-index: auto;
    transition: none;
  }

  .page__backdrop {
    display: none !important;
  }

  .page__fab {
    display: none;
  }
}