platform-bi-web/app/components/chartDesigner/sections/barConfigForm.less

.barconfig-yaxis {
    .ant-cascader-picker-label {
        height: 100%;
        padding: 0 6px;
        .cascader-label {
            margin-left: 6px;
        }
        .empty-label {
            color: #bfbfbf;
        }
    }
}