/* ============================================================
   Mobile / tablet layer (loaded after app.css)
   ≤1024  off-canvas sidebar + hamburger
   ≤768   stacked layouts, scrolling tables, compact topbar
   ≤640   bottom-sheet modals, full-width controls
   ============================================================ */
.menu-btn, .search-btn { display: none; }
html { -webkit-text-size-adjust: 100%; }
img, video, canvas, svg { max-width: 100%; }
.main, .content { min-width: 0; }
.content { overflow-x: clip; padding-bottom: calc(24px + env(safe-area-inset-bottom)); }
.tabs-nav { overflow-x: auto; -webkit-overflow-scrolling: touch; }

@media (max-width: 1024px) {
    .sidebar { transform: translateX(-102%); width: min(86vw, 300px); transition: transform .25s ease; padding-bottom: env(safe-area-inset-bottom); z-index: 400; }
    .sidebar.open { transform: translateX(0); box-shadow: var(--shadow-lg); }
    .sidebar-overlay { position: fixed; inset: 0; background: var(--overlay); z-index: 390; display: block; opacity: 0; pointer-events: none; transition: opacity .2s; }
    .sidebar-overlay.show { opacity: 1; pointer-events: auto; }
    body.nav-open { overflow: hidden; }
    .main { margin-left: 0 !important; }
    .menu-btn { display: grid; }
    .stats-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .content { padding: 20px; }
}

@media (max-width: 900px) {
    .auth-wrap { grid-template-columns: 1fr; }
    .auth-left { display: none; }
    .auth-right { padding: 24px 16px; align-items: start; }
    .chat-wrap { grid-template-columns: 1fr !important; }
    .chat-wrap .chat-main { display: none; }
    .chat-wrap.chat-open .conv-list { display: none; }
    .chat-wrap.chat-open .chat-main { display: flex; }
    .chat-back { display: grid !important; }
    .chat-wrap { height: calc(100vh - 120px); height: calc(100dvh - 120px); }
    .msg-bubble { max-width: 85%; }
}

@media (max-width: 768px) {
    :root { --topbar-h: 58px; }
    .topbar { padding: 0 10px; gap: 6px; }
    .topbar .search { display: none; position: fixed; left: 10px; right: 10px; top: calc(var(--topbar-h) + 6px); max-width: none; z-index: 120; }
    .topbar.search-open .search { display: block; }
    .topbar.search-open .search input { box-shadow: var(--shadow-lg); }
    .search-btn { display: grid; }
    .user-menu .um-text { display: none; }
    .user-menu { padding: 4px; }
    .topbar-actions { gap: 2px; }
    .lang-switch a { padding: 7px 8px; }
    .content { padding: 14px; }
    .page-header { flex-direction: column; align-items: stretch; gap: 10px; margin-bottom: 16px; }
    .page-header > div:last-child:not(:first-child) { display: flex; flex-wrap: wrap; gap: 8px; }
    .page-header .btn { justify-content: center; }
    .page-title { font-size: 20px; }
    .card-header { flex-wrap: wrap; gap: 8px; padding: 14px 16px; }
    .card-body { padding: 16px; }
    /* Any inline multi-column grid collapses to a single column */
    [style*="grid-template-columns"]:not(.cal-grid):not(.cal-summary):not(.stats-grid) { grid-template-columns: minmax(0, 1fr) !important; }
    [style*="display:flex"][style*="gap"], .flex { flex-wrap: wrap; }
    .form-row { grid-template-columns: minmax(0, 1fr) !important; }
    .table-wrap, .card-body:has(> .table), .card:has(> .table) { overflow-x: auto; -webkit-overflow-scrolling: touch; }
    .table { min-width: 560px; }
    .table th, .table td { padding: 10px 12px; }
    .detail-row { flex-direction: column; gap: 2px; }
    .auth-card { padding: 22px 18px; }
    .face-auth-box video, video { max-width: 100%; height: auto; }
    .toast-container { left: 10px; right: 10px; top: 10px; }
    .toast { min-width: 0; width: 100%; }
    .notif-panel { left: 10px; right: 10px; width: auto; top: calc(var(--topbar-h) + 4px); }
    .profile-hero { flex-direction: column; align-items: flex-start; }
    .meeting-shell { padding: 10px; }
}

@media (max-width: 640px) {
    body { font-size: 15px; }
    .stats-grid { grid-template-columns: 1fr; gap: 12px; }
    .stat-card { padding: 16px; }
    .btn { min-height: 42px; }
    .btn-sm { min-height: 36px; }
    .icon-btn { width: 42px; height: 42px; }
    input, select, textarea, .form-control { font-size: 16px !important; }
    .modal-backdrop { align-items: flex-end; padding: 0; }
    .modal { max-width: none; width: 100%; margin: 0; border-radius: 16px 16px 0 0; max-height: 92vh; max-height: 92dvh; padding-bottom: env(safe-area-inset-bottom); }
    .modal-body { padding: 18px 16px; }
    .modal-footer { flex-wrap: wrap; }
    .modal-footer .btn { flex: 1 1 auto; justify-content: center; }
    .brand-text { display: none; }
    .lightbox img { max-width: 96vw; }
}

@media (max-width: 380px) {
    .content { padding: 10px; }
    .topbar .lang-switch { display: none; }
}

@media (hover: none) { .stat-card:hover { transform: none; box-shadow: none; } }
@media print { .sidebar, .topbar, .toast-container, .sidebar-overlay { display: none !important; } .main { margin: 0 !important; } }