Twitter bootstrap 使用NPM在引导4中启用Flexbox网格

我刚刚测试了Bootstrap4，由于某些原因，我无法启用Flexbox网格

以下是我的基本SCSS项目结构，以备不时之需：

styles
├── framework
│   ├── vendor
│   │   ├── _bootstrap.scss
│   │
│   ├── _custom.scss
│
├── main.scss

我正在将我的所有引导SASS文件从NPM导入一个基本的

\u Bootstrap.scss

文件：

/*!
 * Bootstrap v4.0.0-alpha.4 (http://getbootstrap.com)
 * Copyright 2011-2016 The Bootstrap Authors
 * Copyright 2011-2016 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 */

// Core variables and mixins
@import "../../../../node_modules/bootstrap/scss/custom";
@import "../../../../node_modules/bootstrap/scss/variables";
@import "../../../../node_modules/bootstrap/scss/mixins";

// Reset and dependencies
@import "../../../../node_modules/bootstrap/scss/normalize";
@import "../../../../node_modules/bootstrap/scss/print";

// Core CSS
@import "../../../../node_modules/bootstrap/scss/reboot";
@import "../../../../node_modules/bootstrap/scss/type";
@import "../../../../node_modules/bootstrap/scss/images";
@import "../../../../node_modules/bootstrap/scss/code";
@import "../../../../node_modules/bootstrap/scss/grid";
@import "../../../../node_modules/bootstrap/scss/tables";
@import "../../../../node_modules/bootstrap/scss/forms";
@import "../../../../node_modules/bootstrap/scss/buttons";

// Components
@import "../../../../node_modules/bootstrap/scss/animation";
@import "../../../../node_modules/bootstrap/scss/dropdown";
@import "../../../../node_modules/bootstrap/scss/button-group";
@import "../../../../node_modules/bootstrap/scss/input-group";
@import "../../../../node_modules/bootstrap/scss/custom-forms";
@import "../../../../node_modules/bootstrap/scss/nav";
@import "../../../../node_modules/bootstrap/scss/navbar";
@import "../../../../node_modules/bootstrap/scss/card";
@import "../../../../node_modules/bootstrap/scss/breadcrumb";
@import "../../../../node_modules/bootstrap/scss/pagination";
@import "../../../../node_modules/bootstrap/scss/tags";
@import "../../../../node_modules/bootstrap/scss/jumbotron";
@import "../../../../node_modules/bootstrap/scss/alert";
@import "../../../../node_modules/bootstrap/scss/progress";
@import "../../../../node_modules/bootstrap/scss/media";
@import "../../../../node_modules/bootstrap/scss/list-group";
@import "../../../../node_modules/bootstrap/scss/responsive-embed";
@import "../../../../node_modules/bootstrap/scss/close";

// Components w/ JavaScript
@import "../../../../node_modules/bootstrap/scss/modal";
@import "../../../../node_modules/bootstrap/scss/tooltip";
@import "../../../../node_modules/bootstrap/scss/popover";
@import "../../../../node_modules/bootstrap/scss/carousel";

// Utility classes
@import "../../../../node_modules/bootstrap/scss/utilities";

我还有一个

\u custom.scss

，它位于放置引导的供应商文件夹之外：

// Bootstrap overrides
//
// Copy variables from `_variables.scss` to this file to override default values
// without modifying source files.

$enable-flex:               true;

如您所见，

\u custom.scss

文件包含

$enable flex

变量，并设置为true

然后，我有一个

main.scss

文件，它将所有内容连接在一起，如下所示：

// Bootstrap Vendor Imported From NPM
@import "framework/vendor/bootstrap";
// Custom Variables For Bootstrap
@import "framework/custom";

当我尝试使用网格时，所有内容仍然设置为浮动，并且我的_custom.scss文件没有启用flex网格

如果我更改NPM引导包文件夹中的

\u custom.scss

，网格将启用，但是我不能将其用作解决方案，就像其他人使用我的项目并运行NPM一样，这将被覆盖

任何关于这可能不起作用的建议都将非常感谢