.sidebar-scroll::-webkit-scrollbar { width: 6px; }
.sidebar-scroll::-webkit-scrollbar-thumb { background: #e5e7eb; border-radius: 999px; }
.act-btn { position: relative; }
.act-btn::after {
  content: attr(data-tip);
  position: absolute; left: 50%; bottom: calc(100% + 8px); transform: translateX(-50%);
  padding: 4px 8px; border-radius: 4px; background: #1f2937; color: #fff;
  font-size: 12px; line-height: 1.2; white-space: nowrap; opacity: 0; pointer-events: none;
  transition: opacity 0.15s ease; z-index: 40;
}
.act-btn:hover::after { opacity: 1; }