.menu-bar {
  height: 40px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 0 16px;
  border-bottom: 1px solid #fff;
  position: relative;
  z-index: 40; /* ドロップダウンがキャンバスの背面に回らないようにする */
}

.app-title {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  font-weight: bold;
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
}

.menu-item {
  cursor: pointer;
  user-select: none;
  position: relative;
}

/* 親要素にopacityをかけると重なり順が変わりちらつく/透けるため、ラベルのみに適用 */
.menu-item:hover > .menu-label {
  opacity: 0.7;
}

.menu-dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  margin-top: 8px;
  background: #111;
  border: 1px solid #fff;
  border-radius: 4px;
  min-width: 170px;
  flex-direction: column;
  z-index: 30;
  overflow: hidden;
}

.menu-dropdown.open {
  display: flex;
}

.menu-dropdown button {
  background: transparent;
  border: none;
  color: #fff;
  text-align: left;
  padding: 8px 14px;
  font-size: 13px;
  cursor: pointer;
}

.menu-dropdown button:hover {
  background: #fff;
  color: #000;
}

#timeline-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: block;
}

.transport-bar {
  height: 48px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 16px;
  border-top: 1px solid #fff;
}