#app {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

/* ── Title Bar ── */
#title-bar {
  display: flex;
  align-items: center;
  height: var(--titlebar-h);
  background: var(--bg-titlebar);
  color: var(--text-on-accent);
  padding: 0 8px;
  flex-shrink: 0;
  gap: 8px;
  user-select: none;
}
#title-bar-left  { display: flex; align-items: center; gap: 8px; min-width: 200px; }
#title-bar-center { flex: 1; display: flex; justify-content: center; }
#title-bar-right { display: flex; align-items: center; gap: 4px; min-width: 200px; justify-content: flex-end; }

#app-logo { width: 22px; height: 22px; flex-shrink: 0; }
#doc-name {
  font-size: 13px;
  font-weight: 600;
  color: #fff;
  outline: none;
  border-bottom: 1px solid transparent;
  padding: 2px 4px;
  max-width: 300px;
  white-space: nowrap;
  overflow: hidden;
  cursor: text;
}
#doc-name:focus { border-bottom-color: rgba(255,255,255,0.6); }

.title-btn {
  width: 28px; height: 28px;
  border-radius: 4px;
  color: #fff;
  font-size: 14px;
  display: flex; align-items: center; justify-content: center;
  transition: background var(--tr);
}
.title-btn:hover { background: rgba(255,255,255,0.15); }

/* ── Menu Bar inside title bar ── */
#menu-bar { display: flex; gap: 2px; }
.menu-item {
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 12.5px;
  color: rgba(255,255,255,0.92);
  cursor: pointer;
  position: relative;
  transition: background var(--tr);
}
.menu-item:hover, .menu-item.open { background: rgba(255,255,255,0.18); }

.menu-dropdown {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  background: var(--bg-dialog);
  border: 1px solid var(--border);
  border-radius: 4px;
  box-shadow: var(--shadow-popup);
  min-width: 180px;
  z-index: 1000;
  display: none;
  padding: 4px 0;
}
.menu-item.open .menu-dropdown { display: block; }

.menu-dropdown-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  font-size: 13px;
  color: var(--text-primary);
  cursor: pointer;
  white-space: nowrap;
}
.menu-dropdown-item:hover { background: var(--accent-light); }
.menu-dropdown-item .menu-shortcut { margin-left: auto; color: var(--text-muted); font-size: 11px; }
.menu-dropdown-sep { height: 1px; background: var(--border); margin: 4px 0; }

/* ── Ribbon ── */
#ribbon {
  background: var(--bg-ribbon);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  user-select: none;
}
#ribbon-tabs {
  display: flex;
  padding: 0 8px;
  border-bottom: 1px solid var(--border);
  background: #EEF0F5;
}
.rtab {
  padding: 6px 14px;
  font-size: 12.5px;
  color: var(--text-secondary);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: color var(--tr);
}
.rtab:hover { color: var(--accent); }
.rtab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
  background: var(--bg-ribbon-tab-active);
  font-weight: 600;
}

#ribbon-panels { padding: 4px 8px; }
.rpanel { display: none; gap: 4px; align-items: stretch; }
.rpanel.active { display: flex; flex-wrap: wrap; }

.rgroup {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  border-right: 1px solid var(--border);
  padding: 0 8px;
  min-width: fit-content;
}
.rgroup:last-child { border-right: none; }
.rgroup-label {
  font-size: 10px;
  color: var(--text-muted);
  text-align: center;
  margin-top: 2px;
  letter-spacing: 0.03em;
}
.rgroup-buttons { display: flex; gap: 2px; flex-wrap: wrap; align-items: center; }

/* Toolbar Buttons */
.tbtn {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  min-width: 28px; height: 52px;
  border-radius: 3px;
  padding: 2px 4px;
  font-size: 13px;
  color: var(--text-primary);
  cursor: pointer;
  transition: background var(--tr);
  position: relative;
}
.tbtn:hover  { background: var(--bg-toolbar-hover); }
.tbtn.active { background: var(--bg-toolbar-active); }
.tbtn.pressed { background: var(--bg-toolbar-active); box-shadow: inset 0 1px 2px rgba(0,0,0,0.15); }

.tbtn .tbtn-icon  { font-size: 16px; line-height: 1; }
.tbtn .tbtn-label { font-size: 9.5px; color: var(--text-secondary); margin-top: 2px; white-space: nowrap; }

/* Small inline buttons */
.tbtn-sm {
  display: flex; align-items: center; justify-content: center;
  width: 24px; height: 24px;
  border-radius: 3px;
  font-size: 12px;
  color: var(--text-primary);
  cursor: pointer;
  transition: background var(--tr);
}
.tbtn-sm:hover  { background: var(--bg-toolbar-hover); }
.tbtn-sm.active { background: var(--bg-toolbar-active); }

/* Font controls */
.font-family-wrap, .font-size-wrap { display: flex; align-items: center; gap: 2px; }
#font-family {
  width: 130px; height: 24px;
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 0 4px;
  font-size: 12px;
  background: #fff;
  cursor: pointer;
}
#font-family:focus { outline: none; border-color: var(--border-focus); }

#font-size-display {
  width: 44px; height: 24px;
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 0 4px;
  font-size: 12px;
  text-align: center;
  background: #fff;
  cursor: pointer;
}
#font-size-display:focus { outline: none; border-color: var(--border-focus); }

/* Color buttons with swatch */
.color-btn-wrap { display: flex; flex-direction: column; align-items: center; }
.color-swatch-bar {
  height: 3px; width: 18px; border-radius: 1px; margin-top: 1px;
}

/* Ruler Wrapper */
#ruler-wrapper {
  display: flex;
  height: var(--ruler-h);
  background: #E8E8E8;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  position: relative;
}
#ruler-corner {
  width: 22px;
  height: var(--ruler-h);
  background: #E0E0E0;
  border-right: 1px solid var(--border);
  flex-shrink: 0;
  cursor: pointer;
}
#ruler-horizontal {
  flex: 1;
  position: relative;
  overflow: hidden;
}
#ruler-canvas { display: block; width: 100%; height: 100%; }

/* Workspace */
#workspace {
  display: flex;
  flex: 1;
  overflow: hidden;
}

#page-area {
  flex: 1;
  overflow-y: auto;
  overflow-x: auto;
  background: var(--bg-app);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--page-gap) 0 60px;
}