:root {
  --bg-dark:        #1e1e1e;
  --bg-sidebar:     #252526;
  --bg-panel:       #2d2d2d;
  --bg-editor:      #1e1e1e;
  --bg-tab:         #2d2d30;
  --bg-tab-active:  #1e1e1e;
  --bg-input:       #3c3c3c;
  --bg-hover:       #2a2d2e;
  --bg-selected:    #094771;
  --bg-statusbar:   #007acc;
  --bg-titlebar:    #323233;
  --bg-button:      #0e639c;
  --bg-button-hov:  #1177bb;
  --bg-modal:       #252526;
  --bg-overlay:     rgba(0,0,0,0.6);
  --fg-primary:     #cccccc;
  --fg-secondary:   #969696;
  --fg-muted:       #6d6d6d;
  --fg-link:        #9cdcfe;
  --fg-string:      #ce9178;
  --fg-comment:     #6a9955;
  --fg-number:      #b5cea8;
  --fg-type:        #4ec9b0;
  --fg-function:    #dcdcaa;
  --fg-heading:     #569cd6;
  --border:         #3e3e3e;
  --accent:         #007acc;
  --accent-green:   #4ec9b0;
  --sidebar-w:      260px;
  --titlebar-h:     35px;
  --tab-h:          35px;
  --statusbar-h:    22px;
  --font-ui:        'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono:      'Cascadia Code', 'Fira Code', 'Consolas', 'Courier New', monospace;
  --radius:         4px;
  --transition:     0.15s ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  scrollbar-width: thin;
  scrollbar-color: #424242 transparent;
}

/* ===== AUTH SCREEN ===== */
#auth-screen {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: #111;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-ui);
}

#auth-screen.hidden {
  display: none;
}

.auth-box {
  background: var(--bg-modal);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 40px 36px;
  width: 380px;
  max-width: 92vw;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  box-shadow: 0 24px 64px rgba(0,0,0,0.7);
}

.auth-logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.auth-logo h1 {
  font-size: 24px;
  font-weight: 300;
  color: var(--fg-primary);
}

.auth-logo span {
  color: var(--accent);
  font-weight: 700;
}

.auth-subtitle {
  font-size: 12px;
  color: var(--fg-muted);
  text-align: center;
  line-height: 1.5;
}

.auth-field {
  width: 100%;
  position: relative;
}

.auth-label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  color: var(--fg-secondary);
  margin-bottom: 5px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.auth-input-wrap {
  position: relative;
  width: 100%;
}

.auth-field input {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 40px 10px 14px;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 14px;
  outline: none;
  transition: border-color 0.15s;
}

.auth-field input:focus {
  border-color: var(--accent);
}

.auth-field input.err {
  border-color: #f44747;
  animation: shake 0.3s ease;
}

.auth-eye {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  cursor: pointer;
  color: var(--fg-muted);
  font-size: 14px;
  padding: 2px;
}

.auth-eye:hover {
  color: var(--fg-primary);
}

.auth-submit {
  width: 100%;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  padding: 10px;
  font-family: var(--font-ui);
  font-size: 14px;
  cursor: pointer;
  font-weight: 600;
  transition: background 0.15s;
}

.auth-submit:hover {
  background: var(--bg-button-hov);
}

.auth-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.auth-error {
  font-size: 12px;
  color: #f44747;
  min-height: 16px;
  text-align: center;
}

.auth-session {
  font-size: 11px;
  color: var(--fg-muted);
  text-align: center;
}

.view-badge {
  display: none;
  background: #4ec9b0;
  color: #000;
  border-radius: 3px;
  padding: 1px 7px;
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.view-badge.visible {
  display: inline-block;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}

/* ===== BASE & APP GRID ===== */
html, body {
  height: 100%;
  overflow: hidden;
  background: var(--bg-dark);
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 13px;
  line-height: 1.5;
}

::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #424242; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #5a5a5a; }

#app {
  display: grid;
  grid-template-rows: var(--titlebar-h) 1fr var(--statusbar-h);
  grid-template-columns: var(--sidebar-w) 1fr;
  grid-template-areas:
    "titlebar titlebar"
    "sidebar  main"
    "statusbar statusbar";
  height: 100vh;
  height: 100dvh;
  width: 100vw;
}

#app.sidebar-collapsed {
  grid-template-columns: 0px 1fr;
}

/* ===== TITLE BAR ===== */
#titlebar {
  grid-area: titlebar;
  background: var(--bg-titlebar);
  border-bottom: 1px solid #111;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 0 12px;
  user-select: none;
  position: relative;
}

.tb-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 14px;
  color: var(--fg-primary);
  margin-right: 12px;
}

.tb-btn {
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--fg-secondary);
  font-size: 12px;
  font-family: var(--font-ui);
  padding: 4px 10px;
  border-radius: var(--radius);
  transition: background var(--transition), color var(--transition);
  display: flex;
  align-items: center;
  gap: 5px;
  white-space: nowrap;
}

.tb-btn:hover {
  background: rgba(255,255,255,0.08);
  color: var(--fg-primary);
}

.tb-sep {
  width: 1px;
  height: 18px;
  background: var(--border);
  margin: 0 4px;
}

.tb-spacer {
  flex: 1;
}

.tb-path {
  color: var(--fg-muted);
  font-size: 11px;
}

/* ===== SIDEBAR ===== */
#sidebar {
  grid-area: sidebar;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px 4px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg-secondary);
  user-select: none;
}

.sidebar-header-btns {
  display: flex;
  gap: 2px;
}

.icon-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--fg-secondary);
  padding: 3px 5px;
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), color var(--transition);
  font-size: 12px;
}

.icon-btn:hover {
  background: rgba(255,255,255,0.1);
  color: var(--fg-primary);
}

#search-box-wrap {
  padding: 6px 8px;
  border-bottom: 1px solid var(--border);
}

#search-box {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 4px 8px;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 12px;
  outline: none;
  transition: border-color var(--transition);
}

#search-box:focus {
  border-color: var(--accent);
}

#search-box::placeholder {
  color: var(--fg-muted);
}

#filetree {
  flex: 1;
  overflow-y: auto;
  padding: 4px 0;
}

.tree-empty {
  padding: 16px 12px;
  color: var(--fg-muted);
  font-size: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tree-empty p {
  line-height: 1.6;
}

/* ===== TREE NODES ===== */
.tree-item {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 3px 4px 3px 6px;
  cursor: pointer;
  user-select: none;
  color: var(--fg-primary);
  font-size: 13px;
  white-space: nowrap;
  overflow: hidden;
}

.tree-item:hover {
  background: var(--bg-hover);
}

.tree-item.active {
  background: var(--bg-selected);
}

.tree-item .item-label {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
}

.tree-item .item-actions {
  display: none;
  gap: 2px;
  padding-right: 4px;
  flex-shrink: 0;
}

.tree-item:hover .item-actions {
  display: flex;
}

.tree-item .item-action-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--fg-secondary);
  padding: 1px 4px;
  border-radius: 2px;
  font-size: 11px;
}

.tree-item .item-action-btn:hover {
  background: rgba(255,255,255,0.12);
  color: var(--fg-primary);
}

.tree-folder-children {
  display: none;
}

.tree-folder-children.open {
  display: block;
}

/* ===== MAIN AREA & TABS ===== */
#main {
  grid-area: main;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-editor);
}

#tabs-bar {
  height: var(--tab-h);
  background: var(--bg-tab);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: flex-end;
  overflow-x: auto;
  overflow-y: hidden;
  flex-shrink: 0;
}

#tabs-bar::-webkit-scrollbar {
  height: 3px;
}

.tab {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0 14px;
  height: 35px;
  min-width: 80px;
  max-width: 200px;
  background: var(--bg-tab);
  border-right: 1px solid var(--border);
  color: var(--fg-secondary);
  font-size: 12px;
  cursor: pointer;
  user-select: none;
  white-space: nowrap;
  overflow: hidden;
  flex-shrink: 0;
  transition: background var(--transition), color var(--transition);
}

.tab:hover {
  background: var(--bg-hover);
  color: var(--fg-primary);
}

.tab.active {
  background: var(--bg-tab-active);
  color: var(--fg-primary);
  border-top: 1px solid var(--accent);
}

.tab-label {
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 1;
}

.tab-close {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--fg-muted);
  font-size: 16px;
  padding: 0 2px;
  border-radius: 2px;
  line-height: 1;
  flex-shrink: 0;
  transition: background var(--transition), color var(--transition);
  margin-left: 2px;
}

.tab-close:hover {
  background: rgba(255,255,255,0.12);
  color: var(--fg-primary);
}

.tab.modified .tab-label::after {
  content: ' \25CF';
  font-size: 9px;
  color: #e2c08d;
}

/* ===== EDITOR TOOLBAR ===== */
#editor-toolbar {
  min-height: 34px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 2px 8px;
  flex-shrink: 0;
  flex-wrap: wrap;
}

.toolbar-group {
  display: flex;
  gap: 2px;
  align-items: center;
  flex-wrap: wrap;
}

.toolbar-sep {
  width: 1px;
  height: 18px;
  background: var(--border);
  margin: 0 6px;
}

.toolbar-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--fg-secondary);
  padding: 3px 7px;
  border-radius: var(--radius);
  font-size: 11px;
  font-family: var(--font-ui);
  display: flex;
  align-items: center;
  gap: 3px;
  transition: background var(--transition), color var(--transition);
  white-space: nowrap;
}

.toolbar-btn:hover {
  background: rgba(255,255,255,0.08);
  color: var(--fg-primary);
}

.toolbar-btn.active {
  background: rgba(0,122,204,0.25);
  color: var(--accent);
}

.toolbar-spacer {
  flex: 1;
}

/* ===== CONTENT AREA & WELCOME ===== */
#content-area {
  flex: 1;
  display: flex;
  overflow: hidden;
}

#welcome-screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 40px;
  background: var(--bg-editor);
}

.welcome-logo {
  display: flex;
  align-items: center;
  gap: 16px;
}

.welcome-logo h1 {
  font-size: 30px;
  font-weight: 300;
  color: var(--fg-primary);
}

.welcome-logo span {
  color: var(--accent);
  font-weight: 700;
}

.welcome-sub {
  color: var(--fg-secondary);
  font-size: 13px;
  text-align: center;
  max-width: 480px;
  line-height: 1.8;
}

.welcome-actions {
  display: flex;
  gap: 12px;
}

.w-btn {
  padding: 9px 20px;
  border-radius: var(--radius);
  font-family: var(--font-ui);
  font-size: 13px;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition);
}

.w-btn-primary {
  background: var(--accent);
  color: #fff;
}

.w-btn-primary:hover {
  background: var(--bg-button-hov);
}

.w-btn-secondary {
  background: transparent;
  color: var(--fg-secondary);
  border-color: var(--border);
}

.w-btn-secondary:hover {
  border-color: var(--fg-secondary);
  color: var(--fg-primary);
}

kbd {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 1px 5px;
  font-size: 10px;
  font-family: var(--font-mono);
  color: var(--fg-primary);
}

.shortcut-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 5px 16px;
  font-size: 12px;
}

.shortcut-grid span:nth-child(odd) {
  color: var(--fg-muted);
}

/* ===== EDITOR & PREVIEW PANES ===== */
#editor-pane {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

#editor-pane.split {
  flex: 0 0 50%;
  border-right: 1px solid var(--border);
}

#editor-textarea {
  flex: 1;
  width: 100%;
  resize: none;
  background: var(--bg-editor);
  color: var(--fg-primary);
  border: none;
  outline: none;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.65;
  padding: 20px 24px;
  tab-size: 2;
  overflow-y: auto;
}

#preview-pane {
  flex: 1;
  overflow-y: auto;
  padding: 24px 40px;
  background: var(--bg-editor);
  display: none;
  position: relative;
  scroll-behavior: smooth;
}

#preview-pane.visible {
  display: block;
}

#preview-pane.split {
  flex: 1;
  display: block;
}

/* ===== TREE INDEX (OUTLINE) ===== */
#preview-toc {
  width: 250px;
  background: var(--bg-sidebar);
  border-left: 1px solid var(--border);
  display: none;
  flex-direction: column;
  overflow: hidden;
  flex-shrink: 0;
  user-select: none;
}

#preview-toc.visible {
  display: flex;
}

#btn-unhide-toc {
  position: sticky;
  top: 0;
  float: right;
  margin: -12px -24px 0 0;
  z-index: 20;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  color: var(--fg-primary);
  border-radius: 999px;
  padding: 4px 10px;
  font-size: 11px;
  font-family: var(--font-ui);
  cursor: pointer;
  display: none;
  align-items: center;
  gap: 4px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

#btn-unhide-toc:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 10px 6px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg-secondary);
  border-bottom: 1px solid var(--border);
}

.toc-header-btns {
  display: flex;
  gap: 2px;
}

.toc-search-wrap {
  padding: 6px 8px;
  border-bottom: 1px solid var(--border);
}

.toc-search {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 4px 8px;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 12px;
  outline: none;
}

.toc-search:focus {
  border-color: var(--accent);
}

.toc-tree {
  flex: 1;
  overflow-y: auto;
  padding: 6px 0;
  font-size: 12.5px;
}

.toc-node {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 3px 8px 3px 6px;
  cursor: pointer;
  color: var(--fg-primary);
  white-space: nowrap;
  overflow: hidden;
  border-left: 2px solid transparent;
}

.toc-node:hover {
  background: var(--bg-hover);
}

.toc-node.active {
  background: var(--bg-selected);
  border-left-color: var(--accent);
  color: #fff;
  font-weight: 600;
}

.toc-toggle {
  width: 14px;
  height: 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 9px;
  color: var(--fg-secondary);
  flex-shrink: 0;
  border-radius: 2px;
}

.toc-toggle:hover {
  background: rgba(255,255,255,0.12);
  color: var(--fg-primary);
}

.toc-label {
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 1;
}

.toc-children {
  display: none;
  margin-left: 11px;
  border-left: 1px solid var(--border);
}

.toc-children.open {
  display: block;
}

.toc-empty {
  padding: 14px 12px;
  color: var(--fg-muted);
  font-size: 12px;
}

/* ===== MARKDOWN STYLES ===== */
.md-body {
  max-width: 760px;
  margin: 0 auto;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.8;
}

.md-body h1, .md-body h2, .md-body h3, .md-body h4, .md-body h5, .md-body h6 {
  color: var(--fg-heading);
  font-weight: 600;
  margin: 1.4em 0 0.5em;
  line-height: 1.3;
}

.md-body h1 {
  font-size: 2em;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.3em;
}

.md-body h2 {
  font-size: 1.5em;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.2em;
}

.md-body h3 {
  font-size: 1.25em;
}

.md-body p {
  margin: 0.8em 0;
}

.md-body a {
  color: var(--fg-link);
  text-decoration: none;
}

.md-body a:hover {
  text-decoration: underline;
}

.md-body ul, .md-body ol {
  padding-left: 2em;
  margin: 0.6em 0;
}

.md-body li {
  margin: 0.3em 0;
}

.md-body blockquote {
  border-left: 3px solid var(--accent);
  margin: 1em 0;
  padding: 8px 16px;
  background: rgba(0,122,204,0.08);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--fg-secondary);
}

.md-body hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 1.5em 0;
}

.md-body table {
  border-collapse: collapse;
  width: 100%;
  margin: 1em 0;
}

.md-body th {
  background: var(--bg-panel);
  font-weight: 600;
}

.md-body th, .md-body td {
  border: 1px solid var(--border);
  padding: 8px 12px;
  text-align: left;
}

.md-body tr:nth-child(even) td {
  background: rgba(255,255,255,0.02);
}

.md-body img {
  max-width: 100%;
  border-radius: var(--radius);
  margin: 0.5em 0;
}

.md-body code {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 1px 5px;
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--fg-string);
}

.md-body pre {
  background: #0d0d0d;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  overflow-x: auto;
  margin: 1em 0;
  position: relative;
}

.md-body pre code {
  background: none;
  border: none;
  padding: 0;
  color: var(--fg-primary);
  font-size: 13px;
}

.md-body pre .lang-label {
  position: absolute;
  top: 6px;
  right: 10px;
  font-size: 10px;
  color: var(--fg-muted);
  font-family: var(--font-mono);
  text-transform: uppercase;
}

.tok-keyword { color: #c586c0; }
.tok-string  { color: #ce9178; }
.tok-comment { color: #6a9955; font-style: italic; }
.tok-number  { color: #b5cea8; }

.md-body input[type=checkbox] {
  margin-right: 6px;
  accent-color: var(--accent);
}

.md-body li.task-item {
  list-style: none;
  margin-left: -1.5em;
}

/* ===== TEXT COLOR & HIGHLIGHT PALETTE ===== */
.md-body mark, .md-bg-yellow {
  background: rgba(242,204,96,0.22);
  color: #f2cc60;
  padding: 1px 6px;
  border-radius: 4px;
  border: 1px solid rgba(242,204,96,0.35);
}
.md-c-red    { color: #ff6b6b; }
.md-c-blue   { color: #58a6ff; }
.md-c-green  { color: #3fb950; }
.md-c-yellow { color: #f2cc60; }
.md-c-orange { color: #ffa657; }
.md-c-purple { color: #d2a8ff; }
.md-c-cyan   { color: #56d4dd; }
.md-c-pink   { color: #ff7b9c; }

.md-bg-red    { background: rgba(255,107,107,0.18); color: #ff8787; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(255,107,107,0.35); }
.md-bg-blue   { background: rgba(88,166,255,0.18);  color: #79c0ff; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(88,166,255,0.35); }
.md-bg-green  { background: rgba(63,185,80,0.18);   color: #56d364; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(63,185,80,0.35); }
.md-bg-orange { background: rgba(255,166,87,0.18);  color: #ffb77c; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(255,166,87,0.35); }
.md-bg-purple { background: rgba(210,168,255,0.18); color: #e2c5ff; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(210,168,255,0.35); }
.md-bg-cyan   { background: rgba(86,212,221,0.18);  color: #76e3ea; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(86,212,221,0.35); }
.md-bg-pink   { background: rgba(255,123,156,0.18); color: #ff9bce; padding: 1px 6px; border-radius: 4px; border: 1px solid rgba(255,123,156,0.35); }

.color-dot-btn {
  padding: 3px 5px !important;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.color-dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
  display: inline-block;
  border: 1px solid rgba(255,255,255,0.25);
}

/* ===== STATUS BAR ===== */
#statusbar {
  grid-area: statusbar;
  background: var(--bg-statusbar);
  color: rgba(255,255,255,0.9);
  display: flex;
  align-items: center;
  font-size: 11px;
  user-select: none;
  overflow: hidden;
}

.sb-item {
  padding: 0 10px;
  height: 100%;
  display: flex;
  align-items: center;
  white-space: nowrap;
}

.sb-item:hover {
  background: rgba(0,0,0,0.15);
  cursor: default;
}

.sb-item.left {
  border-right: 1px solid rgba(255,255,255,0.15);
}

.sb-spacer {
  flex: 1;
}

.sb-item.right {
  border-left: 1px solid rgba(255,255,255,0.15);
}

/* ===== MODAL ===== */
#modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
}

#modal-overlay.visible {
  display: flex;
}

.modal {
  background: var(--bg-modal);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  min-width: 360px;
  box-shadow: 0 16px 48px rgba(0,0,0,0.6);
}

.modal h2 {
  font-size: 15px;
  margin-bottom: 12px;
}

.modal input {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 7px 10px;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 13px;
  outline: none;
  transition: border-color var(--transition);
}

.modal input:focus {
  border-color: var(--accent);
}

.modal-actions {
  display: flex;
  gap: 8px;
  justify-content: flex-end;
  margin-top: 16px;
}

.modal-btn {
  padding: 6px 16px;
  border-radius: var(--radius);
  cursor: pointer;
  font-family: var(--font-ui);
  font-size: 12px;
  border: 1px solid transparent;
  transition: all var(--transition);
}

.modal-btn-primary {
  background: var(--accent);
  color: #fff;
}

.modal-btn-primary:hover {
  background: var(--bg-button-hov);
}

.modal-btn-cancel {
  background: transparent;
  color: var(--fg-secondary);
  border-color: var(--border);
}

.modal-btn-cancel:hover {
  border-color: var(--fg-secondary);
  color: var(--fg-primary);
}

/* ===== CONTEXT MENU ===== */
#ctx-menu {
  position: fixed;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 4px 0;
  min-width: 180px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.5);
  z-index: 999;
  display: none;
}

#ctx-menu.visible {
  display: block;
}

.ctx-item {
  padding: 6px 16px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--fg-primary);
  font-size: 13px;
  transition: background var(--transition);
}

.ctx-item:hover {
  background: var(--bg-selected);
}

.ctx-item.danger {
  color: #f44747;
}

.ctx-item.danger:hover {
  background: rgba(244,71,71,0.15);
}

.ctx-sep {
  height: 1px;
  background: var(--border);
  margin: 4px 0;
}

/* ===== NOTIFICATIONS ===== */
#notifications {
  position: fixed;
  bottom: 30px;
  right: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  z-index: 2000;
}

.notif {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 8px 14px;
  font-size: 12px;
  color: var(--fg-primary);
  box-shadow: 0 4px 12px rgba(0,0,0,0.4);
  animation: notif-in 0.2s ease;
  max-width: 280px;
}

.notif.success {
  border-left-color: #4ec9b0;
}

.notif.error {
  border-left-color: #f44747;
}

@keyframes notif-in {
  from { opacity: 0; transform: translateX(20px); }
  to { opacity: 1; transform: translateX(0); }
}

/* ===== HELP ===== */
#help-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
}

#help-overlay.hidden {
  display: none;
}

/* ===== USER MANAGEMENT CONTROL PANEL ===== */
#users-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.72);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
  z-index: 1050;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

#users-overlay.hidden {
  display: none;
}

.um-modal {
  background: var(--bg-modal);
  border: 1px solid var(--border);
  border-radius: 10px;
  width: 920px;
  max-width: 96vw;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.65);
  overflow: hidden;
}

.um-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 22px;
  background: var(--bg-titlebar);
  border-bottom: 1px solid var(--border);
}

.um-header-title {
  display: flex;
  align-items: center;
  gap: 12px;
}

.um-icon {
  font-size: 24px;
  background: rgba(0, 122, 204, 0.18);
  border: 1px solid rgba(0, 122, 204, 0.4);
  width: 42px;
  height: 42px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.um-header h2 {
  font-size: 16px;
  font-weight: 600;
  color: var(--fg-primary);
}

.um-header p {
  font-size: 12px;
  color: var(--fg-secondary);
  margin-top: 2px;
}

.um-close-btn {
  background: none;
  border: none;
  color: var(--fg-secondary);
  font-size: 24px;
  cursor: pointer;
  line-height: 1;
  padding: 4px 8px;
  border-radius: 4px;
}

.um-close-btn:hover {
  background: var(--bg-hover);
  color: var(--fg-primary);
}

.um-body {
  padding: 18px 22px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.um-stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.um-stat-card {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  padding: 10px 14px;
}

.um-stat-card.role-admin { border-left-color: #f2cc60; }
.um-stat-card.role-editor { border-left-color: #4ec9b0; }
.um-stat-card.role-viewer { border-left-color: #58a6ff; }

.um-stat-val {
  font-size: 20px;
  font-weight: 700;
  color: var(--fg-primary);
}

.um-stat-lbl {
  font-size: 11px;
  color: var(--fg-secondary);
  margin-top: 2px;
}

.um-card {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}

.um-card-hdr {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: rgba(0, 0, 0, 0.2);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-secondary);
}

.um-btn-link {
  background: none;
  border: 1px solid var(--border);
  color: var(--fg-primary);
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 4px;
  cursor: pointer;
}

.um-btn-link:hover {
  background: var(--bg-hover);
}

.um-form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1.2fr 1.3fr auto;
  gap: 12px;
  padding: 14px 16px;
  align-items: end;
}

.um-field label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  color: var(--fg-secondary);
  margin-bottom: 5px;
}

.um-field input,
.um-field select {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 7px 10px;
  color: var(--fg-primary);
  font-size: 12px;
  outline: none;
}

.um-field select {
  -webkit-appearance: menulist;
  appearance: menulist;
  cursor: pointer;
}

.um-field input:focus,
.um-field select:focus {
  border-color: var(--accent);
}

.um-pass-wrap {
  display: flex;
  gap: 6px;
}

.um-gen-btn {
  background: var(--bg-titlebar);
  border: 1px solid var(--border);
  color: var(--fg-primary);
  border-radius: 4px;
  padding: 0 9px;
  font-size: 11px;
  cursor: pointer;
  white-space: nowrap;
}

.um-gen-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.um-submit-btn {
  background: var(--bg-button);
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 8px 16px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}

.um-submit-btn:hover {
  background: var(--bg-button-hov);
}

.um-hdr-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

#um-search {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  color: var(--fg-primary);
  font-size: 12px;
  outline: none;
  width: 180px;
}

#um-search:focus {
  border-color: var(--accent);
}

.um-refresh-btn {
  background: var(--bg-titlebar);
  border: 1px solid var(--border);
  color: var(--fg-primary);
  border-radius: 4px;
  padding: 4px 10px;
  font-size: 11px;
  cursor: pointer;
}

.um-refresh-btn:hover {
  border-color: var(--accent);
}

.um-table-wrap {
  overflow-x: auto;
}

.um-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12.5px;
}

.um-table th,
.um-table td {
  padding: 10px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.um-table th {
  font-size: 11px;
  font-weight: 600;
  color: var(--fg-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: rgba(0, 0, 0, 0.12);
}

.um-table tr:last-child td {
  border-bottom: none;
}

.um-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.um-user-cell {
  display: flex;
  align-items: center;
  gap: 10px;
}

.um-avatar {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--bg-selected);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 12px;
  flex-shrink: 0;
}

.um-user-name {
  font-weight: 600;
  color: var(--fg-primary);
}

.um-user-sub {
  font-size: 11px;
  color: var(--fg-muted);
}

.um-role-select {
  background: var(--bg-input);
  border: 1px solid var(--border);
  color: var(--fg-primary);
  border-radius: 4px;
  padding: 4px 8px;
  font-size: 12px;
  font-weight: 600;
  -webkit-appearance: menulist;
  appearance: menulist;
  cursor: pointer;
}

.um-role-select.role-admin { border-color: rgba(242, 204, 96, 0.5); color: #f2cc60; }
.um-role-select.role-editor { border-color: rgba(78, 201, 176, 0.5); color: #4ec9b0; }
.um-role-select.role-viewer { border-color: rgba(88, 166, 255, 0.5); color: #58a6ff; }

.um-status-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
}

.um-status-badge.active {
  background: rgba(63, 185, 80, 0.16);
  color: #3fb950;
  border-color: rgba(63, 185, 80, 0.35);
}

.um-status-badge.disabled {
  background: rgba(244, 71, 71, 0.16);
  color: #f44747;
  border-color: rgba(244, 71, 71, 0.35);
}

.um-action-btns {
  display: flex;
  justify-content: flex-end;
  gap: 6px;
}

.um-act-btn {
  background: var(--bg-titlebar);
  border: 1px solid var(--border);
  color: var(--fg-primary);
  border-radius: 4px;
  padding: 4px 8px;
  font-size: 11px;
  cursor: pointer;
}

.um-act-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.um-act-btn.danger:hover {
  border-color: #f44747;
  color: #f44747;
}

@media (max-width: 820px) {
  .um-stats-row { grid-template-columns: repeat(2, 1fr); }
  .um-form-grid { grid-template-columns: 1fr 1fr; }
}

.hidden {
  display: none !important;
}

/* ===== CROSS-BROWSER & TOUCH DEVICE COMPATIBILITY ===== */
#titlebar, #sidebar, #tabs-bar, #editor-toolbar, #statusbar, #preview-toc, #ctx-menu {
  -webkit-user-select: none;
  user-select: none;
}

input, textarea, button {
  -webkit-appearance: none;
  appearance: none;
  font-family: inherit;
}

select {
  font-family: inherit;
}

@media (hover: none), (pointer: coarse) {
  .tree-item .item-actions {
    display: flex;
  }
  .tab .tab-close {
    opacity: 0.85;
  }
}