#header {
  height: 132px;
}

#header::after {
  clear: both;
  display: table;
  content: " ";
}

/* 全局：回到顶部按钮（滚动超过阈值后显示） */
.hnbq-backtotop {
  position: fixed;
  right: 18px;
  bottom: 22px;
  z-index: 9999;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 10px;
  background: rgba(56, 108, 190, 0.92);
  color: #fff;
  font-size: 18px;
  line-height: 44px;
  text-align: center;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.22);
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity 160ms ease, transform 160ms ease, background 160ms ease;
}

.hnbq-backtotop:hover {
  background: rgba(56, 108, 190, 1);
}

.hnbq-backtotop.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

@media (max-width: 768px) {
  .hnbq-backtotop {
    right: 12px;
    bottom: 14px;
    width: 42px;
    height: 42px;
    line-height: 42px;
    border-radius: 12px;
  }
}