/* ============================================
   VTU PLATFORM — LAYOUT
   Top bar, bottom nav, sidebar, page structure
   ============================================ */


/* ─── TOP BAR ───────────────────────────────
   ─────────────────────────────────────────── */

.top-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--top-bar-height);
  background: var(--bg-base);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--page-padding-x);
  z-index: var(--z-sticky);
  max-width: var(--max-content-width);
  margin: 0 auto;

  /* Subtle blur for depth */
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

/* Full-width top bar (admin) */
.top-bar--full {
  max-width: 100%;
  left: var(--sidebar-width);
}

.top-bar__left {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.top-bar__logo {
  height: 28px;
  width: auto;
}

.top-bar__title {
  font-size: var(--text-md);
  font-weight: var(--font-semi);
  color: var(--text-primary);
}

.top-bar__back {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color var(--transition-fast);
  margin-left: -6px;
}
.top-bar__back:hover {
  background: var(--bg-hover);
}

.top-bar__right {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.top-bar__icon-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  cursor: pointer;
  transition:
    background-color var(--transition-fast),
    color var(--transition-fast);
  position: relative;
}
.top-bar__icon-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* Notification badge on icon */
.top-bar__badge {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 8px;
  height: 8px;
  background: var(--danger);
  border-radius: var(--radius-full);
  border: 1.5px solid var(--bg-base);
}

/* Number badge */
.top-bar__badge--count {
  width: auto;
  min-width: 16px;
  height: 16px;
  padding: 0 4px;
  font-size: 9px;
  font-weight: var(--font-bold);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  top: 2px;
  right: 2px;
}


/* ─── BOTTOM NAVIGATION ─────────────────────
   ─────────────────────────────────────────── */

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--bottom-nav-height);
  background: var(--bg-base);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  z-index: var(--z-sticky);
  max-width: var(--max-content-width);
  margin: 0 auto;
  padding: 0 var(--space-xs);

  /* Safe area for notched phones */
  padding-bottom: env(safe-area-inset-bottom);
}

.bottom-nav__item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: var(--space-xs);
  cursor: pointer;
  border-radius: var(--radius-md);
  transition:
    background-color var(--transition-fast),
    color var(--transition-fast);
  color: var(--text-muted);
  -webkit-tap-highlight-color: transparent;
  position: relative;
}
.bottom-nav__item:hover {
  background: var(--bg-hover);
}
.bottom-nav__item.is-active {
  color: var(--text-primary);
}

.bottom-nav__icon {
  width: 22px;
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Active indicator dot */
.bottom-nav__item.is-active::before {
  content: '';
  position: absolute;
  top: 6px;
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
}

.bottom-nav__label {
  font-size: 10px;
  font-weight: var(--font-medium);
  letter-spacing: 0.2px;
}

/* Middle action button (AI chat) */
.bottom-nav__item--center {
  position: relative;
}
.bottom-nav__item--center .bottom-nav__icon {
  width: 44px;
  height: 44px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
  color: var(--bg-base);
  font-size: 20px;
  margin-top: -8px;
}
.bottom-nav__item--center.is-active::before {
  display: none;
}


/* ─── SIDEBAR (Admin / Desktop) ─────────────
   ─────────────────────────────────────────── */

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--sidebar-width);
  background: var(--bg-card);
  border-right: 1px solid var(--border-soft);
  display: flex;
  flex-direction: column;
  z-index: var(--z-sticky);
  overflow-y: auto;
}

.sidebar__header {
  padding: var(--space-lg) var(--space-md);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.sidebar__logo {
  height: 28px;
}

.sidebar__nav {
  flex: 1;
  padding: var(--space-md) var(--space-sm);
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar__section-label {
  font-size: var(--text-xs);
  font-weight: var(--font-semi);
  color: var(--text-muted);
  letter-spacing: 0.8px;
  text-transform: uppercase;
  padding: var(--space-md) var(--space-sm) var(--space-xs);
}

.sidebar__item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 10px var(--space-sm);
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  transition:
    background-color var(--transition-fast),
    color var(--transition-fast);
}
.sidebar__item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}
.sidebar__item.is-active {
  background: var(--bg-elevated);
  color: var(--text-primary);
}
.sidebar__item .icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.sidebar__footer {
  padding: var(--space-md);
  border-top: 1px solid var(--border-subtle);
}


/* ─── PAGE SECTIONS ─────────────────────────
   ─────────────────────────────────────────── */

.page-section {
  margin-bottom: var(--space-lg);
}

/* Stack layout */
.stack {
  display: flex;
  flex-direction: column;
}
.stack--xs  { gap: var(--space-xs); }
.stack--sm  { gap: var(--space-sm); }
.stack--md  { gap: var(--space-md); }
.stack--lg  { gap: var(--space-lg); }
.stack--xl  { gap: var(--space-xl); }

/* Row layout */
.row {
  display: flex;
  align-items: center;
}
.row--between { justify-content: space-between; }
.row--center  { justify-content: center; }
.row--end     { justify-content: flex-end; }
.row--xs  { gap: var(--space-xs); }
.row--sm  { gap: var(--space-sm); }
.row--md  { gap: var(--space-md); }
.row--lg  { gap: var(--space-lg); }

/* Grid */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-sm); }
.grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: var(--space-sm); }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-sm); }


/* ─── MODAL ─────────────────────────────────
   ─────────────────────────────────────────── */

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: var(--z-modal);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}
.modal-overlay.is-open {
  opacity: 1;
  pointer-events: all;
}

.modal {
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  padding: var(--space-md);
  padding-bottom: calc(var(--space-xl) + env(safe-area-inset-bottom));
  width: 100%;
  max-width: var(--max-content-width);
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(100%);
  transition: transform var(--transition-spring);
}
.modal-overlay.is-open .modal {
  transform: translateY(0);
}

.modal__handle {
  width: 36px;
  height: 4px;
  background: var(--border-soft);
  border-radius: var(--radius-full);
  margin: 0 auto var(--space-lg);
}

.modal__title {
  font-size: var(--text-md);
  font-weight: var(--font-semi);
  text-align: center;
  color: var(--text-primary);
  margin-bottom: var(--space-lg);
}

/* Center modal (for confirmations) */
.modal--center {
  border-radius: var(--radius-xl);
  margin: var(--space-lg);
  max-height: 80vh;
  transform: scale(0.95);
  transition: transform var(--transition-spring), opacity var(--transition-normal);
}
.modal-overlay--center {
  align-items: center;
}
.modal-overlay--center.is-open .modal--center {
  transform: scale(1);
}


/* ─── PIN PAD ───────────────────────────────
   ─────────────────────────────────────────── */

.pin-pad {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg) 0;
}

.pin-pad__title {
  font-size: var(--text-md);
  font-weight: var(--font-semi);
  color: var(--text-primary);
}

.pin-pad__subtitle {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-top: -var(--space-sm);
}

.pin-dots {
  display: flex;
  gap: var(--space-md);
}

.pin-dot {
  width: 14px;
  height: 14px;
  border-radius: var(--radius-full);
  border: 2px solid var(--border-active);
  background: transparent;
  transition:
    background-color var(--transition-fast),
    border-color var(--transition-fast),
    transform var(--transition-spring);
}
.pin-dot.is-filled {
  background: var(--text-primary);
  border-color: var(--text-primary);
  transform: scale(1.1);
}
.pin-dot.is-error {
  border-color: var(--danger);
  background: var(--danger);
}

.pin-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-sm);
  width: 280px;
}

.pin-key {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 72px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border-soft);
  cursor: pointer;
  transition:
    background-color var(--transition-fast),
    transform var(--transition-fast);
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}
.pin-key:hover { background: var(--bg-hover); }
.pin-key:active {
  transform: scale(0.93);
  background: var(--bg-elevated);
}
.pin-key--empty {
  background: transparent;
  border-color: transparent;
  cursor: default;
}
.pin-key--empty:hover { background: transparent; }
.pin-key--empty:active { transform: none; }

.pin-key__number {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: var(--font-semi);
  color: var(--text-primary);
  line-height: 1;
}
.pin-key__letters {
  font-size: 9px;
  color: var(--text-muted);
  letter-spacing: 1px;
  margin-top: 2px;
}
.pin-key__icon {
  font-size: 20px;
  color: var(--text-primary);
}


/* ─── RESPONSIVE ────────────────────────────
   ─────────────────────────────────────────── */

/* Tablet and up */
@media (min-width: 640px) {
  :root {
    --page-padding-x: 24px;
  }
}

/* Desktop */
@media (min-width: 1024px) {
  .bottom-nav {
    display: none; /* Use sidebar on desktop */
  }
  .page-wrapper {
    padding-bottom: var(--space-2xl);
  }
  .top-bar {
    max-width: 100%;
    left: var(--sidebar-width);
  }
}

/* Mobile only — hide sidebar */
@media (max-width: 1023px) {
  .sidebar {
    display: none;
  }
  .page-wrapper--sidebar {
    margin-left: 0;
    padding: 0 var(--page-padding-x);
    padding-bottom: calc(var(--bottom-nav-height) + var(--space-lg));
    padding-top: calc(var(--top-bar-height) + var(--space-md));
    max-width: var(--max-content-width);
  }
}


/* ─── APP SHELL VISIBILITY ──────────────────
   Controlled by JS class toggle, never style=
   ─────────────────────────────────────────── */

.app-shell--hidden {
  display: none;
}

.app-nav--hidden {
  display: none;
}

/* Page loading fade */
.page-content--loading {
  opacity: 0.6;
  pointer-events: none;
}