/* =====================================================================
 * Cursor-like three-column workspace
 *
 *   [left file explorer] | [middle document reader] | [right chat]
 *
 * Loaded after product.css — this file owns the final layout for the
 * new columns and the generic expandable directory tree. Older layout
 * rules that target removed markup (#action-rail, #doc-columns,
 * workspace modes, ...) simply go unused.
 * ===================================================================== */

:root {
  --sidebar-width-default: clamp(210px, 18vw, 300px);
  --doc-content-font-size: var(--md-font-size, 15px);
}

/* ---------- body / shell ---------- */

body {
  min-width: 0;
}

.boot-placeholder {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 13px;
}

#sidebar {
  flex: 0 0 auto;
  width: var(--sidebar-width-default);
  min-width: 180px;
  max-width: 360px;
}

#sidebar.collapsed {
  width: 44px !important;
  min-width: 44px !important;
  max-width: 44px !important;
  flex-basis: auto !important;
}

#explorer-resize {
  width: 6px;
  flex: 0 0 6px;
  cursor: col-resize;
  background: linear-gradient(
    to right,
    transparent 0,
    transparent 2px,
    var(--resize-divider) 2px,
    var(--resize-divider) 4px,
    transparent 4px
  );
}

#explorer-resize:hover,
#explorer-resize.dragging {
  background: linear-gradient(
    to right,
    transparent 0,
    transparent 2px,
    var(--accent) 2px,
    var(--accent) 4px,
    transparent 4px
  );
}

/* ---------- sidebar / left explorer ---------- */

#sidebar-header {
  padding: var(--space-3) var(--space-2) var(--space-3);
  grid-template-columns: minmax(0, 1fr) 32px;
  gap: var(--space-2);
}

#file-explorer {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
}



.file-root-tab:hover {
  background: var(--hover-bg);
  color: var(--text);
}

.file-root-tab.active {
  background: var(--toolbar-menu-selected-bg);
  color: var(--text1);
  font-weight: 500;
}

#file-root-tabs {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  gap: 2px;
  padding: 6px 8px 5px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  overflow: hidden;
}

.file-root-tab {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  min-width: 0;
  flex: 0 1 auto;
  height: 24px;
  padding: 0 6px;
  border: 1px solid transparent;
  border-radius: 6px;
  background: transparent;
  color: var(--text2);
  font-size: 11.5px;
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  transition: background 0.12s ease, color 0.12s ease;
}

.file-root-tab:hover {
  background: var(--hover-bg);
  color: var(--text);
}

.file-root-tab.active {
  background: var(--toolbar-menu-selected-bg);
  color: var(--text1);
  font-weight: 500;
}

.file-root-tab-icon {
  width: 12px;
  height: 12px;
  flex: 0 0 auto;
  color: inherit;
  opacity: 0.85;
}

.file-root-tab-label {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-refresh-btn {
  margin-left: auto;
  width: 26px;
  height: 26px;
}

#file-tree {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 6px 6px 14px;
}

.file-tree-empty {
  padding: 18px 8px;
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}

.file-tree-row {
  display: flex;
  align-items: center;
  gap: 5px;
  height: 27px;
  padding: 0 8px 0 6px;
  border-radius: 7px;
  cursor: pointer;
  font-size: 12.5px;
  color: var(--text2);
  white-space: nowrap;
  user-select: none;
  transition: background 0.12s ease, color 0.12s ease;
}

.file-tree-row:hover {
  background: var(--hover-bg);
  color: var(--text);
}

.file-tree-row.active {
  background: var(--toolbar-menu-selected-bg);
  color: var(--text1);
  font-weight: 500;
}

.tree-chevron {
  width: 14px;
  height: 14px;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  transition: transform 0.12s ease;
}

.tree-chevron i {
  width: 13px;
  height: 13px;
}

.tree-chevron.open {
  transform: rotate(90deg);
}

.tree-chevron-placeholder {
  visibility: hidden;
}

.tree-icon {
  width: 15px;
  height: 15px;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
}

.tree-icon i {
  width: 15px;
  height: 15px;
}

.file-tree-row.active .tree-icon,
.file-tree-row:hover .tree-icon {
  color: var(--text2);
}

.tree-label {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}

#sidebar.collapsed #file-explorer,
#sidebar.collapsed .sidebar-brand h1 {
  display: none;
}

/* ---------- main shell: document | chat ---------- */

#main-shell {
  display: flex;
  min-width: 0;
  min-height: 0;
}

/* ---------- middle: document reader ---------- */

#document-panel {
  flex: 1;
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
  background: var(--bg);
}

#document-panel #doc-tabs {
  flex: 0 0 auto;
  border: 0;
  border-bottom: 1px solid var(--border);
  border-radius: 0;
}

#document-panel #doc-preview-toolbar {
  flex: 0 0 auto;
  height: 38px;
  min-height: 38px;
  border: 0;
  border-bottom: 1px solid var(--border);
  border-radius: 0;
  padding: 5px 12px;
  background: var(--bg4);
}

#doc-preview-content {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 26px 34px 48px;
  font-family: var(--md-font-family);
  font-size: var(--md-font-size);
  line-height: 1.7;
  white-space: pre-wrap;
  background: var(--bg);
  color: var(--text);
}

#doc-preview-content.markdown-body {
  white-space: normal;
}

#doc-preview-content.image-preview {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 18px;
  user-select: none;
}

#doc-preview-content.unsupported {
  color: var(--muted);
}

#doc-preview-content .doc-edit-textarea {
  display: block;
  width: 100%;
  height: 100%;
  border: none;
  outline: none;
  resize: none;
  padding: 0;
  font-family: var(--md-font-family);
  font-size: var(--md-font-size);
  line-height: 1.7;
  color: var(--text1);
  background: transparent;
  white-space: pre-wrap;
  tab-size: 2;
}

.doc-empty-state {
  height: 100%;
  min-height: 240px;
}

.doc-toolbar-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

#doc-refresh-btn,
#doc-edit-btn,
#doc-save-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  height: 26px;
  padding: 0 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text2);
  font-size: 12px;
  cursor: pointer;
  flex-shrink: 0;
  transition: background 0.12s ease, color 0.12s ease, border-color 0.12s ease;
}

#doc-refresh-btn .lucide,
#doc-edit-btn .lucide,
#doc-save-btn .lucide {
  width: 14px;
  height: 14px;
}

#doc-refresh-btn:hover:not(:disabled),
#doc-edit-btn:hover:not(:disabled),
#doc-save-btn:hover:not(:disabled) {
  background: var(--hover-bg);
  color: var(--text1);
  border-color: var(--border-strong);
}

#doc-refresh-btn:disabled,
#doc-edit-btn:disabled,
#doc-save-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

#doc-edit-btn.editing,
#doc-save-btn {
  color: var(--success);
  border-color: color-mix(in srgb, var(--success) 45%, var(--border));
}

#doc-save-btn:hover:not(:disabled) {
  background: var(--success-soft);
}

/* ---------- chat column ---------- */

#chat-rail-resize {
  width: 6px;
  flex: 0 0 6px;
  cursor: col-resize;
  background: linear-gradient(
    to right,
    transparent 0,
    transparent 2px,
    var(--resize-divider) 2px,
    var(--resize-divider) 4px,
    transparent 4px
  );
}

#chat-rail-resize:hover,
#chat-rail-resize.dragging {
  background: linear-gradient(
    to right,
    transparent 0,
    transparent 2px,
    var(--accent) 2px,
    var(--accent) 4px,
    transparent 4px
  );
}

#chat-panel {
  flex: 0 0 auto;
  width: 440px;
  min-width: 320px;
  background: var(--bg);
  border-left: 0;
}

#chat-header {
  min-height: 52px;
  padding: 8px 10px 8px 12px;
  gap: 6px;
}

#chat-meta {
  flex: 1;
  min-width: 0;
  max-width: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

#chat-meta #new-session-btn {
  flex: 0 0 auto;
  width: auto;
  height: 30px;
  min-height: 30px;
  margin: 0;
  padding: 0 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: 999px;
  background: var(--accent);
  color: var(--accent-text);
  font-size: 12.5px;
  box-shadow: none;
}

#chat-meta #new-session-btn:hover {
  background: var(--accent-hover);
}

#chat-meta #new-session-btn .lucide {
  width: 14px;
  height: 14px;
}

#chat-title {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-size: 13px;
  font-weight: var(--weight-semibold);
  color: var(--text1);
}

#chat-title.is-placeholder {
  color: var(--muted);
  font-weight: var(--weight-normal);
}

#chat-toolbar {
  margin-left: 0;
}

.header-icon-btn {
  width: 30px;
  height: 30px;
}

#chat-body {
  position: relative;
  flex: 1;
  min-width: 0;
  min-height: 0;
  display: flex;
}

#chat-content {
  flex: 1;
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
}

#chat-body.show-home #chat-content {
  display: none;
}

/* ---------- chat home (session history view) ---------- */

#chat-home {
  position: absolute;
  inset: 0;
  z-index: 6;
  display: none;
  flex-direction: column;
  background: var(--bg);
}

#chat-body.show-home #chat-home {
  display: flex;
}

.chat-home-scroll {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  padding: 26px 20px 20px;
}

.chat-home-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 6px;
  padding: 10px 0 22px;
}

.chat-home-brand {
  width: 46px;
  height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  background: var(--empty-state-icon-bg);
  border-radius: 14px;
  margin-bottom: 8px;
}

.chat-home-brand .lucide {
  width: 22px;
  height: 22px;
}

.chat-home-title {
  font-size: 15px;
  font-weight: var(--weight-semibold);
  color: var(--text1);
}

.chat-home-copy {
  font-size: 12.5px;
  color: var(--muted);
  max-width: 260px;
  line-height: 1.55;
}

.chat-home-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
}

#chat-home-new-btn {
  height: 32px;
  padding: 0 16px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border-radius: 999px;
  border: 1px solid var(--accent);
  background: var(--accent);
  color: var(--accent-text);
  font-size: 13px;
  cursor: pointer;
}

#chat-home-new-btn:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

#chat-home-new-btn .lucide {
  width: 15px;
  height: 15px;
}

#chat-home-resume-btn {
  height: 32px;
  padding: 0 14px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text2);
  font-size: 13px;
  cursor: pointer;
}

#chat-home-resume-btn:hover {
  background: var(--hover-bg);
  color: var(--text1);
}

.chat-home-history {
  padding-top: 10px;
  border-top: 1px solid var(--border);
}

.chat-home-history-title {
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-transform: uppercase;
  padding: 4px 4px 8px;
}

#chat-home #session-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

#chat-home .session-item {
  min-height: 44px;
  margin-bottom: 0;
}

/* ---------- composer inside the narrower chat column ---------- */

#input-area {
  padding: 10px 12px 14px;
}

#composer {
  width: 100%;
  max-width: 100%;
}

#messages {
  --conversation-content-max-width: 720px;
}

#messages .message,
#messages .message.user {
  max-width: min(100%, var(--conversation-content-max-width, 720px));
}

/* ---------- small screen guards ---------- */

@media (max-width: 900px) {
  #sidebar:not(.collapsed) {
    width: min(46vw, var(--sidebar-width-default, 240px)) !important;
    min-width: 160px;
    flex-basis: auto;
  }
  #chat-panel {
    width: min(46vw, 420px) !important;
    min-width: 300px;
  }
  #doc-preview-content {
    padding: 18px 20px 40px;
  }
}

#workspace-switch {
  display: flex;
  gap: 2px;
  padding: 0 8px 6px;
  flex-shrink: 0;
}

#sidebar.collapsed #workspace-switch {
  display: none;
}

#workspace-switch button,
#people-toolbar button,
.people-panes button {
  border: 1px solid var(--line, #ddd);
  background: transparent;
  border-radius: 8px;
  padding: 2px 8px;
}

#workspace-switch button.active,
#people-toolbar button.active,
.people-panes button.active,
.people-row.active {
  background: var(--surface-2, #f3f0e8);
}

body.people-workspace #file-root-tabs,
body.people-workspace #file-tree,
body.people-workspace #doc-view-tabs,
body.people-workspace #doc-preview-toolbar,
body.people-workspace #doc-preview-content {
  display: none;
}

#people-browser[hidden] {
  display: none;
}

#people-browser:not([hidden]) {
  display: flex;
  flex-direction: column;
  min-height: 0;
  flex: 1;
}

#people-list {
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 8px;
}

.people-row {
  text-align: left;
  border: 0;
  background: transparent;
  padding: 8px;
}

.people-row span,
.people-entry header,
.people-day {
  color: var(--muted);
  font-size: 12px;
}

#people-stage {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 0;
  flex: 1;
  overflow: auto;
  padding: 12px;
}

.people-entry {
  max-width: 70%;
  margin: 6px 0;
  padding: 8px 10px;
  border-radius: 12px;
  background: var(--surface-2, #f3f0e8);
}

.people-entry.mine {
  margin-left: auto;
}

#people-profile,
#people-text,
.people-doc {
  width: 100%;
  white-space: pre-wrap;
}