/*使屏幕变暗  */
.background_screen {
  width: 100%;
  height: 100%;
  position: fixed;
  top: 0;
  left: 0;
  background: #000;
  opacity: 0.4;
  overflow: hidden;
  z-index: 99;
  color: #fff;
}
/*对话框 */
.attr_box {
  width: 100%;
  max-height: 80vh;
  position: fixed;
  bottom: 0;
  left: 0;
  z-index: 99;
  border-radius: 40px 40px 0 0;
  border-radius: 40px 40px 0px 0px;
  border-top-left-radius: 30rpx;
  border-top-right-radius: 30rpx;
  box-sizing: border-box;
  /*兼容 IOS<11.2*/
  /*兼容 IOS>11.2*/
}
