Modify el-select background image style

1. Original picture------------Rendering picture

 2.  css

/***********大的背景图***************/
.el-popper.is-pure {
    background: url(/src/assets/imgList/memuBG.png) no-repeat;
    border: none;
    background-size: 100% 100%;
}


/*********选中行的字体***********/
.el-select-dropdown__item.selected {
    color: #ffffff;
    font-weight: 700;
}

/*************选中行的背景色****************/
.el-select-dropdown__item.hover, .el-select-dropdown__item:hover {
    background-color: #5793e1;
}