/* ═══════════════════════════════════════════════════════════════
   shell.css — App shell: icon nav + topbar
   Canonical .app-* class names, uses tokens.css variables only.
   Shared by all app-shell pages (index.html, user_management.html,
   and any future standalone pages).
   ═══════════════════════════════════════════════════════════════ */

/* ── Icon Nav ── */
.app-nav {
  --app-nav-bg: var(--bg);
  --app-nav-btn-fg: #64748B;
  --app-nav-btn-hover-bg: #1A1F2E;
  --app-nav-btn-hover-fg: #94A3B8;
  --app-nav-btn-active-bg: #1E2A4A;
  --app-nav-btn-active-fg: #60A5FA;
  width: 3.428571rem;
  background: var(--app-nav-bg);
  border-right: 1px solid var(--bd);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0.714286rem 0;
  gap: 1rem;
  flex-shrink: 0;
  z-index: 10;
  transition: background .2s, border-color .2s;
}
.app-nav-body {
  display: flex;
  flex-direction: column;
  flex: 1;
  width: 100%;
  align-items: center;
}
.app-nav-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.142857rem;
  flex: 1;
  width: 100%;
}
.app-nav-bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.142857rem;
  padding-bottom: 0.285714rem;
  width: 100%;
}

.app-nav-logo {
  width: 2rem;
  height: 2rem;
  border-radius: 0.428571rem;
  background: transparent;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  cursor: default;
}
.app-nav-logo svg { width: 2rem; height: 2rem; }

.app-nav-btn {
  width: 2.571429rem;
  height: 2.571429rem;
  border-radius: 0.571429rem;
  border: none;
  background: transparent;
  color: var(--app-nav-btn-fg);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background .15s, color .15s;
  flex-shrink: 0;
  text-decoration: none;
  position: relative;
}
.app-nav-btn svg { width: 1.285714rem; height: 1.285714rem; }

/* Dark mode states */
.app-nav-btn:hover  { background: var(--app-nav-btn-hover-bg); color: var(--app-nav-btn-hover-fg); }
.app-nav-btn.active { background: var(--app-nav-btn-active-bg); color: var(--app-nav-btn-active-fg); }

/* Light mode states */
[data-mode="light"] .app-nav {
  --app-nav-bg: var(--sur);
  --app-nav-btn-fg: #94A3B8;
  --app-nav-btn-hover-bg: #F1F5F9;
  --app-nav-btn-hover-fg: #475569;
  --app-nav-btn-active-bg: #EFF6FF;
  --app-nav-btn-active-fg: #2563EB;
}

.app-nav-sep {
  width: 1.714286rem;
  height: 1px;
  background: var(--bd);
  margin: 0.285714rem 0;
  opacity: .6;
  flex-shrink: 0;
}

/* ── App Topbar ── */
.app-topbar {
  display: flex;
  align-items: center;
  padding: 0 1.142857rem;
  height: 3.571429rem;
  border-bottom: 1px solid var(--bd);
  background: var(--sur);
  flex-shrink: 0;
  gap: 0.714286rem;
  transition: background .2s, border-color .2s;
}
.app-topbar-title-group {
  display: flex;
  align-items: baseline;
  gap: 0.571429rem;
  flex: 1;
  min-width: 0;
}
.app-topbar-title {
  font-size: 1.142857rem;
  font-weight: 700;
  color: var(--t1);
  white-space: nowrap;
}
.app-topbar-sub {
  font-size: 0.928571rem;
  color: var(--t3);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.app-topbar-actions {
  display: flex;
  align-items: center;
  gap: 0.285714rem;
  flex-shrink: 0;
}
/* Bordered text button (A−, A+) */
.top-btn {
  height: 2rem;
  padding: 0 0.714286rem;
  border-radius: 0.428571rem;
  border: 1px solid var(--bd);
  background: var(--sur2);
  color: var(--t3);
  font-family: var(--f, inherit);
  font-size: 0.785714rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color .15s, color .15s;
}
.top-btn:hover { border-color: var(--bd2, var(--bd)); color: var(--t2); }

/* Borderless icon button */
.top-icon-btn {
  width: 2.142857rem;
  height: 2.142857rem;
  border-radius: 0.428571rem;
  border: none;
  background: transparent;
  color: var(--t3);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background .15s, color .15s;
}
.top-icon-btn:hover { background: var(--sur2); color: var(--t2); }

/* Model selector */
.model-selector {
  display: block;
  height: 2rem;
  padding: 0 0.714286rem;
  border-radius: 0.428571rem;
  border: 1px solid var(--bd);
  background: var(--sur2);
  color: var(--t2);
  font-family: var(--f, inherit);
  font-size: 0.785714rem;
  font-weight: 600;
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
  transition: border-color .15s, color .15s;
}
.model-selector:hover { border-color: var(--bd2, var(--bd)); color: var(--t1); }
.model-selector option { background: var(--sur2); color: var(--t1); }

/* ── User Avatar & Dropdown ── */
.user-avatar-wrap {
  --shell-user-avatar-start: #7C3AED;
  --shell-user-avatar-end: #2563EB;
  --shell-user-avatar-fg: var(--w);
  --shell-user-menu-shadow: var(--sh-md);
  position: relative;
}
.user-avatar-wrap.is-loading .user-menu { display: none !important; }
.user-avatar {
  width: 2.142857rem;
  height: 2.142857rem;
  border-radius: 0.571429rem;
  background: linear-gradient(135deg, var(--shell-user-avatar-start), var(--shell-user-avatar-end));
  color: var(--shell-user-avatar-fg);
  font-size: .7rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  user-select: none;
}
.user-avatar-wrap.is-loading .user-avatar {
  position: relative;
  overflow: hidden;
  color: transparent;
  background: var(--sur2);
  cursor: default;
}
.user-avatar-wrap.is-loading .user-avatar::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, color-mix(in srgb, var(--sur2) 92%, transparent) 0%, color-mix(in srgb, var(--sur3, var(--sur2)) 100%, transparent) 50%, color-mix(in srgb, var(--sur2) 92%, transparent) 100%);
  background-size: 200% 100%;
  animation: shellSkeletonPulse 1.15s ease-in-out infinite;
}
@keyframes shellSkeletonPulse {
  0%, 100% { background-position: 100% 50%; opacity: 0.72; }
  50% { background-position: 0% 50%; opacity: 1; }
}
.user-menu {
  position: absolute;
  top: calc(100% + 0.571429rem);
  right: 0;
  width: 12.857143rem;
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 0.714286rem;
  box-shadow: var(--shell-user-menu-shadow);
  z-index: 200;
  overflow: hidden;
}
.user-menu-profile {
  display: flex;
  align-items: center;
  gap: 0.642857rem;
  padding: 0.857143rem 0.857143rem 0.714286rem;
}
.user-menu-avatar {
  width: 2.285714rem;
  height: 2.285714rem;
  border-radius: 0.571429rem;
  background: linear-gradient(135deg, var(--shell-user-avatar-start), var(--shell-user-avatar-end));
  color: var(--shell-user-avatar-fg);
  font-size: .75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.user-menu-info  { min-width: 0; }
.user-menu-name  { font-size: 0.857143rem; font-weight: 600; color: var(--t1); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.user-menu-role  { font-size: 0.714286rem; color: var(--t3); margin-top: 1px; }
.user-menu-sep   { height: 1px; background: var(--bd); margin: 0 0 4px; }
.user-menu-item {
  display: flex;
  align-items: center;
  gap: 0.642857rem;
  width: 100%;
  padding: 0.642857rem 0.857143rem;
  border: none;
  background: transparent;
  color: var(--t2);
  font-size: 0.857143rem;
  font-family: var(--f, inherit);
  cursor: pointer;
  text-align: left;
  transition: background .12s, color .12s;
}
.user-menu-item:hover { background: var(--sur2); color: var(--t1); }
.user-menu-item:last-child { border-radius: 0 0 0.714286rem 0.714286rem; margin-bottom: 0.285714rem; }
.user-menu-item svg { flex-shrink: 0; }

/* ── App shell grid ──
   3 columns × 2 rows, defined once on body.
   col 1 = app nav  |  col 2 = page sidebar  |  col 3 = topbar + content
   ──────────────────────────────────────────────────────────────────── */
.app-shell-page {
  --sidebar-w: 0px;
  display: grid;
  grid-template-columns: 48px var(--sidebar-w) 1fr;
  grid-template-rows: 50px 1fr;
  height: 100dvh;
  overflow: hidden;
  transition: grid-template-columns .25s ease;
}
.app-shell-page > .app-nav          { grid-column: 1; grid-row: 1 / 3; }
.app-shell-page > .app-page-sidebar { grid-column: 2; grid-row: 1 / 3; display: none; }
.app-shell-page > .app-topbar       { grid-column: 3; grid-row: 1; }
.app-shell-page > .app-body         { grid-column: 3; grid-row: 2; display: flex; flex-direction: column; overflow: hidden; min-width: 0; min-height: 0; background: var(--sur); }

/* Pages with a sidebar: set width + show the sidebar column */
.app-shell-page.page-has-sidebar { --sidebar-w: 210px }
.app-shell-page.page-has-sidebar > .app-page-sidebar {
  display: flex;
  flex-direction: column;
  position: relative;
  background: var(--sur);
  border-right: 1px solid var(--bd);
  overflow: visible;
}

/* Disable grid transition while resizing (avoids lag) */
.app-shell-page.sidebar-resizing { transition: none; }

/* Resize handle — hidden unless body allows it */
.app-page-sidebar-resize {
  position: absolute;
  top: 0;
  right: -2px;
  width: 4px;
  height: 100%;
  cursor: ew-resize;
  background: transparent;
  z-index: 5;
  display: none;
  transition: background .12s;
}
.app-page-sidebar-resize:hover,
.app-page-sidebar-resize.active {
  background: var(--p);
}
body.page-has-sidebar.can-resize-sidebar .app-page-sidebar-resize { display: block; }

/* Collapsed: animate back to 0 */
.app-shell-page.sidebar-collapsed { --sidebar-w: 0px; }

/* Collapsed sidebar */
.page-has-sidebar.sidebar-collapsed {
  grid-template-columns: 48px 0 1fr;
}

/* Sidebar inner — clips page content, not the toggle button */
.app-page-sidebar-inner {
  flex: 1;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.app-page-sidebar .sidebar {
  width: 100%;
  height: 100%;
  min-width: 0;
  border-right: none;
}
.app-page-sidebar .sidebarResizeHandle,
.app-page-sidebar .sidebarCollapseBtn,
.app-page-sidebar .sidebarExpandBtn {
  display: none !important;
}

/* Sidebar toggle button (brown circle in diagram) */
.app-sidebar-toggle {
  position: absolute;
  right: -14px;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 32px;
  border-radius: 0 6px 6px 0;
  border-left: none;
  background: var(--sur);
  border: 1px solid var(--bd);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 20;
  transition: background .12s, color .12s, opacity .15s;
  flex-shrink: 0;
  padding: 0;
  color: var(--t3);
  opacity: 0;
  pointer-events: none;
}
.app-page-sidebar:hover .app-sidebar-toggle,
.sidebar-collapsed .app-sidebar-toggle {
  opacity: 1;
  pointer-events: auto;
}
.app-sidebar-toggle:hover {
  background: var(--sur2);
  color: var(--t1);
}
.app-sidebar-toggle svg {
  width: 10px;
  height: 10px;
  transition: transform .25s ease;
}
/* When collapsed: flip arrow to point right */
.sidebar-collapsed .app-sidebar-toggle svg { transform: rotate(180deg); }
.app-sidebar-toggle svg { transform-origin: center; }

/* ── About Panel ── */
@keyframes aboutIn {
  from { transform: translateX(100%); opacity: 0; }
  to   { transform: translateX(0);    opacity: 1; }
}
@keyframes aboutOut {
  from { transform: translateX(0);    opacity: 1; }
  to   { transform: translateX(100%); opacity: 0; }
}
.about-panel {
  position: fixed;
  top: 50px;
  right: 0;
  bottom: 0;
  width: 280px;
  background: var(--bg);
  border-left: 1px solid var(--bd);
  box-shadow: -4px 0 20px rgba(0,0,0,.12);
  z-index: 999;
  flex-direction: column;
  overflow: hidden;
  display: none;
}
.about-panel.is-open {
  display: flex;
  animation: aboutIn .2s ease;
}
.about-panel.is-closing {
  display: flex;
  animation: aboutOut .2s ease forwards;
}
.about-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px 10px;
  border-bottom: 1px solid var(--bd);
  flex-shrink: 0;
}
.about-title {
  font-size: 0.928571rem;
  font-weight: 600;
  color: var(--t1);
}
.about-close {
  width: 24px;
  height: 24px;
  border-radius: 6px;
  border: none;
  background: transparent;
  color: var(--t3);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  padding: 0;
  transition: background .12s, color .12s;
}
.about-close:hover { background: var(--sur2); color: var(--t1); }

.about-links {
  display: flex;
  flex-direction: column;
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
  flex-shrink: 0;
}
.about-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 16px;
  font-size: 0.857143rem;
  color: var(--t2);
  text-decoration: none;
  transition: background .12s, color .12s;
}
.about-link:hover { background: var(--sur2); color: var(--t1); }
.about-link-icon {
  display: inline-block;
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
  background-color: var(--t3);
  -webkit-mask-size: contain;
  mask-size: contain;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
  -webkit-mask-position: center;
  mask-position: center;
}
.about-ext-icon {
  display: inline-block;
  width: 0.785714rem;
  height: 0.785714rem;
  margin-left: auto;
  flex-shrink: 0;
  background-color: var(--t3);
  opacity: .6;
  -webkit-mask-size: contain;
  mask-size: contain;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
  -webkit-mask-position: center;
  mask-position: center;
}

.about-footer {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 12px 14px 14px;
  margin-top: auto;
  border-top: 1px solid var(--bd);
}
.about-logo {
  height: 1.571429rem;
  width: 100%;
  margin-bottom: 0.428571rem;
  background-color: var(--t2);
  -webkit-mask-size: contain;
  mask-size: contain;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
  -webkit-mask-position: left center;
  mask-position: left center;
}
.about-logo-img {
  width: 22px;
  height: 22px;
  object-fit: contain;
  flex-shrink: 0;
}
.about-logo-text {
  font-size: 1rem;
  font-weight: 700;
  color: var(--t1);
}
.about-product {
  font-size: 0.857143rem;
  font-weight: 600;
  color: var(--t2);
}
.about-meta {
  font-size: 0.785714rem;
  font-weight: 500;
  color: var(--t3);
}
.about-description {
  font-size: 0.785714rem;
  line-height: 1.45;
  color: var(--t3);
}
.about-version {
  font-size: 0.857143rem;
  color: var(--t3);
}
.about-copy {
  font-size: 0.714286rem;
  color: var(--t4, var(--t3));
  margin-top: 2px;
}

/* Home dashboard uses a full-width presentation without shell chrome */
.home-fullwidth.app-shell-page {
  grid-template-columns: 1fr;
  grid-template-rows: 1fr;
}
.home-fullwidth.app-shell-page > .app-nav,
.home-fullwidth.app-shell-page > .app-page-sidebar,
.home-fullwidth.app-shell-page > .app-topbar {
  display: none !important;
}
.home-fullwidth.app-shell-page > .app-body {
  grid-column: 1;
  grid-row: 1;
}