/* 滚动到顶部按钮 */
.scroll-to-top {
  position: fixed;
  bottom: 20px;
  right: 20px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: linear-gradient(135deg, #2563eb 0%, #f59e0b 100%);
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.4);
  transition: all 0.3s ease;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 9998;
  opacity: 0;
  transform: translateY(20px);
}

.scroll-to-top.show {
  display: flex;
  opacity: 1;
  transform: translateY(0);
}

.scroll-to-top:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 30px rgba(37, 99, 235, 0.6);
}

.scroll-to-top svg {
  width: 24px;
  height: 24px;
  fill: #fff;
}

@media (max-width: 768px) {
  .scroll-to-top {
    bottom: 140px;
    right: 15px;
    width: 45px;
    height: 45px;
  }
  
  .scroll-to-top svg {
    width: 20px;
    height: 20px;
  }
}