/* ═══════════════════════════════════════
   LatexCraft v4.0 — layout.css
   Topbar, toolbar, sidebars, editor area, statusbar
   ═══════════════════════════════════════ */

.app {
  display: flex;
  flex-direction: column;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  background: var(--bg-base);
}

/* ─── TOPBAR (52px) ─── */
.topbar {
  height: 52px;
  flex-shrink: 0;
  background: var(--bg-base);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  padding: 0 16px;
  position: relative;
  gap: 12px;
}
.topbar::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-default), transparent);
}
.topbar-logo {
  width: 30px; height: 30px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%);
  color: var(--accent-text);
  border-radius: var(--r-md);
  display: grid;
  place-items: center;
  font: 700 14px/1 var(--font-display);
  box-shadow: 0 2px 12px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,0.15);
  letter-spacing: -0.02em;
}
.topbar-brand {
  font: 600 16px/1 var(--font-ui);
  color: var(--text-primary);
  letter-spacing: -0.01em;
}
.topbar-brand .accent { color: var(--accent); }
.topbar-sep {
  width: 1px; height: 24px;
  background: var(--border-default);
  margin: 0 4px;
}
.topbar-project {
  font: 500 13px/1 var(--font-ui);
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--r-sm);
  padding: 6px 10px;
  width: 200px;
  transition: all var(--t-fast);
}
.topbar-project:hover {
  border-color: var(--border-subtle);
  color: var(--text-primary);
}
.topbar-project:focus {
  background: var(--bg-surface);
  border-color: var(--accent);
  color: var(--text-primary);
  box-shadow: 0 0 0 3px var(--accent-dim);
}
.topbar-actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 6px;
}

/* ─── TOOLBAR (76px) ─── */
.toolbar {
  flex-shrink: 0;
  background: linear-gradient(180deg, var(--bg-surface), var(--bg-void));
  position: relative;
  user-select: none;
}
.toolbar::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-default), transparent);
}
.toolbar-tabs {
  height: 32px;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 0 12px;
  overflow-x: auto;
  scrollbar-width: none;
}
.toolbar-tabs::-webkit-scrollbar { display: none; }
.toolbar-tags {
  height: 44px;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 0 12px;
  overflow-x: auto;
  scrollbar-width: none;
}
.toolbar-tags::-webkit-scrollbar { display: none; }

/* ─── MAIN BODY ─── */
.body {
  flex: 1;
  display: flex;
  min-height: 0;
}

/* ─── LEFT SIDEBAR ─── */
.sidebar {
  width: 52px;
  flex-shrink: 0;
  background: var(--bg-elevated);
  border-right: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  transition: width var(--t-slow) var(--ease-snap);
  overflow: hidden;
  position: relative;
}
.sidebar.expanded { width: 280px; }
.sidebar-tabs {
  display: flex;
  flex-direction: column;
  width: 52px;
  flex-shrink: 0;
  border-right: 1px solid var(--border-subtle);
  background: var(--bg-base);
}
.sidebar-tab {
  width: 52px; height: 52px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all var(--t-fast);
  border-left: 3px solid transparent;
  padding: 0;
}
.sidebar-tab:hover {
  background: var(--bg-hover);
  color: var(--text-secondary);
}
.sidebar-tab:hover svg { transform: scale(1.1); }
.sidebar-tab.active {
  background: var(--bg-elevated);
  color: var(--accent);
  border-left-color: var(--accent);
}
.sidebar-tab svg { transition: transform var(--t-fast); }

.sidebar-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  overflow: hidden;
}
.sidebar-header {
  height: 40px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 14px;
  border-bottom: 1px solid var(--border-subtle);
  font: 600 11px/1 var(--font-ui);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
}
.sidebar-body {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}
.sidebar-collapse {
  position: absolute;
  bottom: 8px; right: 8px;
  width: 24px; height: 24px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-base);
  color: var(--text-muted);
  border-radius: var(--r-xs);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all var(--t-fast);
}
.sidebar-collapse:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* ─── EDITOR AREA ─── */
.workspace {
  flex: 1;
  display: flex;
  min-width: 0;
  position: relative;
}

/* ─── PREVIEW PANEL ─── */
.preview-panel {
  width: 480px;
  flex-shrink: 0;
  background: var(--bg-elevated);
  border-left: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  transition: width var(--t-slow) var(--ease-snap);
  overflow: hidden;
  position: relative;
}
.preview-panel.hidden { width: 0; border-left: none; }
.preview-resize {
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 6px;
  cursor: col-resize;
  z-index: 10;
}
.preview-resize:hover {
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  background-size: 200% 100%;
  animation: shimmer 1.4s linear infinite;
}
.preview-header {
  height: 40px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 14px;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-base);
}
.preview-title {
  font: 600 11px/1 var(--font-ui);
  text-transform: uppercase;
  letter-spacing: 0.10em;
  color: var(--text-secondary);
}
.preview-actions {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ─── STATUS BAR (28px) ─── */
.statusbar {
  height: 28px;
  flex-shrink: 0;
  background: var(--bg-elevated);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  padding: 0 12px;
  gap: 16px;
  font: 400 11px/1 var(--font-ui);
  color: var(--text-muted);
}
.statusbar .status-left { display: flex; gap: 12px; align-items: center; }
.statusbar .status-center { flex: 1; text-align: center; color: var(--text-secondary); }
.statusbar .status-right { display: flex; gap: 12px; align-items: center; font-family: var(--font-editor); }
.save-dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--color-success);
  display: inline-block;
  margin-right: 6px;
}
.save-dot.saving { background: var(--accent); animation: pulse 1.2s infinite; }
.save-dot.error { background: var(--color-error); }
.lint-status {
  display: flex; gap: 4px; align-items: center;
}
.lint-status.ok { color: var(--color-success); }
.lint-status.warn { color: var(--color-warning); }
.lint-status.error { color: var(--color-error); }

/* ─── FOCUS MODE ─── */
.app.focus-mode .topbar,
.app.focus-mode .toolbar,
.app.focus-mode .sidebar,
.app.focus-mode .statusbar { display: none; }
.app.focus-mode .preview-panel { display: none; }
.app.focus-mode .body { padding-top: 0; }
.app.focus-mode::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 100px;
  background: linear-gradient(180deg, var(--bg-base), transparent);
  pointer-events: none;
  z-index: 100;
}
.app.focus-mode::after {
  content: '';
  position: fixed;
  bottom: 0; left: 0; right: 0;
  height: 100px;
  background: linear-gradient(0deg, var(--bg-base), transparent);
  pointer-events: none;
  z-index: 100;
}
.focus-indicator {
  position: fixed;
  bottom: 16px; right: 16px;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--accent);
  z-index: 200;
  display: none;
}
.app.focus-mode .focus-indicator { display: block; animation: pulse 2s infinite; }

/* Typewriter mode: dim non-active lines (works alongside or independently of focus mode) */
.app.typewriter .editor-textarea {
  caret-color: var(--accent);
}
.app.typewriter .editor-highlight {
  /* Soft mask: dim everything except the line band around cursor.
     Implemented with linear-gradient mask. */
  mask-image: linear-gradient(180deg,
    rgba(0,0,0,0.25) 0%,
    rgba(0,0,0,0.25) calc(50% - 32px),
    rgba(0,0,0,1)    calc(50% - 16px),
    rgba(0,0,0,1)    calc(50% + 16px),
    rgba(0,0,0,0.25) calc(50% + 32px),
    rgba(0,0,0,0.25) 100%);
  -webkit-mask-image: linear-gradient(180deg,
    rgba(0,0,0,0.25) 0%,
    rgba(0,0,0,0.25) calc(50% - 32px),
    rgba(0,0,0,1)    calc(50% - 16px),
    rgba(0,0,0,1)    calc(50% + 16px),
    rgba(0,0,0,0.25) calc(50% + 32px),
    rgba(0,0,0,0.25) 100%);
}

/* ─── SIDEBAR LIST ITEMS ─── */
.list-item {
  padding: 8px 10px;
  border-radius: var(--r-sm);
  cursor: pointer;
  transition: background var(--t-fast);
  font: 400 13px/1.3 var(--font-ui);
  color: var(--text-secondary);
  display: flex;
  gap: 8px;
  align-items: center;
}
.list-item:hover { background: var(--bg-hover); color: var(--text-primary); }
.list-item.active {
  background: var(--accent-dim);
  color: var(--accent);
  border-left: 2px solid var(--accent);
}
.list-item.indent-1 { padding-left: 22px; }
.list-item.indent-2 { padding-left: 34px; }
.list-item.indent-3 { padding-left: 46px; }
.list-item-meta {
  margin-left: auto;
  font-family: var(--font-editor);
  font-size: 10px;
  color: var(--text-muted);
}

/* Stats panel (right sidebar style) */
.stats-panel {
  width: 320px;
  background: var(--bg-elevated);
  border-left: 1px solid var(--border-subtle);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  transition: width var(--t-slow) var(--ease-snap), opacity var(--t-base);
  overflow: hidden;
}
.stats-panel.hidden { width: 0; opacity: 0; }
.stats-panel-header {
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 14px;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-base);
  font: 600 11px/1 var(--font-ui);
  text-transform: uppercase;
  letter-spacing: 0.10em;
  color: var(--text-secondary);
}
.stats-panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 14px;
}