html, body {
  margin: 0;
  height: 100%;
  background: transparent;
  overflow: hidden;
  user-select: none;
  -webkit-user-select: none;
  cursor: default;
  font-family: "Segoe UI", "Microsoft JhengHei", "PingFang TC", system-ui, sans-serif;
}

#stage {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-end;
  padding-bottom: 8px;
}

#bubble {
  position: relative;
  max-width: calc(100% - 12px);
  margin-bottom: 10px;
  padding: 6px 11px;
  background: rgba(255, 255, 255, 0.97);
  color: #222;
  border-radius: 12px;
  font-size: 13px;
  line-height: 1.35;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.28);
  overflow: hidden;
  transition: opacity 0.18s ease, transform 0.18s ease;
  cursor: pointer;
}

/* 標題與內文各自佔一行，各自省略；沒有標題時整行收起來 */
#bubble-title,
#bubble-text {
  display: block;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

#bubble-title {
  font-size: 11px;
  line-height: 1.3;
  color: #6b7280;
}

#bubble-title:empty {
  display: none;
}

#bubble::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -6px;
  transform: translateX(-50%);
  border: 6px solid transparent;
  border-top-color: rgba(255, 255, 255, 0.97);
  border-bottom: 0;
}

#bubble.hidden {
  opacity: 0;
  transform: translateY(4px);
  pointer-events: none;
}

#sprite {
  display: block;
}

#sprite.grab {
  cursor: grab;
}

#sprite.grabbing {
  cursor: grabbing;
}
