el-menu弹出菜单样式不生效的问题及解决方法

<template>
    <el-menu
        :default-active="activeMenu"
        :collapse="false"
        :unique-opened="true"
        class="container"
        :collapse-transition="true"
        mode="horizontal"
    >
        <sidebar-item
            v-for="(route, index) in sidebarRouters"
            :key="route.path  + index"
            :item="route"
            :base-path="route.path"
        />
    </el-menu>
</template>

 .container {
    box-shadow: 0px 1px 4px 0px rgba(0,0,0,0.1);
    float: left;
    height:  100%;
    width: 200px;
    background-color: transparent !important;
    overflow: hidden;
    -webkit-transition: width .28s;
    transition: width 0.28s;
    -webkit-box-shadow: 2px 0 6px rgba(0,21,41,.35);
    box-shadow: 2px 0 6px rgba(0,21,41,.35);
    .svg-icon {
        margin-right: 10px;
        margin-left: 3px;
    }
    // menu hover
   .el-submenu__title {
        font-size: 17px;
        color: white !important;
        &:hover {
            background-color: transparent !important;
        }
    }
}

.el-menu--popup {
    .el-submenu__title{
        background-color: #0B1423 !important;
        color: #FFF !important;
    }
    .el-menu-item{
        background-color: #0B1423 !important;
        color: #FFF !important;
    }
    .el-menu-item:hover {
        background-color: #FFF !important;
        color: #0B1423 !important;
    }
    .el-menu-item.is-active {
        background-color: #FFF !important;
        color: #0B1423 !important;
    }
    .svg-icon {
        margin-right: 10px;
        margin-left: 3px;
    }  
}