效果图：

下拉菜单距离顶部有一定的距离，为了避免鼠标滑到二级菜单的过程中，二级菜单意外收起。可以在二级菜单的外部在包裹一层div，然后二级菜单距离外部包裹的div有一定的距离即可。

.right {
    display: flex;
    align-items: center;

    i {
        margin: 0 12px;
        font-style: normal;
    }

    .tj,
    .fbsj {
        position: relative;
        span {
            color: #333;
            font-size: 16px;
            cursor: pointer;
        }

        &:hover .submenu{
            display: block;
        }

        // 二级菜单包裹层
        .submenu{
            display: none;
            position: absolute;
            top: 100%;
            right: 0;
            z-index: 99;
        }
        
        ul {
            width: 92px;
            background-color: #ffffff;
            box-shadow: 0px 0px 10px 0px rgba(0, 0, 0, 0.25);
            border-radius: 4px;
            margin-top: 10px;  //距离父div高度
            li{
                text-align: center;
                height: 36px;
                line-height: 36px;
                font-size: #999;
                cursor: pointer;

                &:hover{
                    background-color: #f1f1f1;
                    color: #333;
                }
            }
        }
    }
}