Twitter Bootstrap中的所有按钮都悬停样式

我想更改悬停按钮的默认样式（Bootstrap v3.2）。默认情况下，它变得更暗。假设我想减轻重量。

I would like to change default styling for hover buttons (Bootstrap v3.2). By default it's becoming darker. Let's assume I would like to make it lighter.

我看着按钮的变量较少，但是我没有看到按钮悬停样式选项。

I looked at Buttons Less variables but I don't see button hover styling option.

在SASS中，我可以这样做：

In SASS I can do:

@import "packages/stylesheets/bootstrap/bootstrap";

.btn {
  &:hover {
    background: yellow;
  }
}

，但是它将所有按钮背景更改为定义的颜色（在这种情况下为黄色）。

but it changes all button background to defined color (in this case yellow).

是否可以对所有按钮进行操作？

Is it possible to do it for all buttons?

我找到的唯一解决方案是id可以为每种类型的按钮做到这一点，但是我希望可以为所有按钮做些简单的事情：

The only solution I found id to do it this for each type of button this way but I hope it can be done for all buttons a bit simpler:

@import "packages/stylesheets/bootstrap/bootstrap";

.btn-primary {
  &:hover {
    background: lighten($btn-primary-bg, 5%);
  }
}
.btn-success {
  &:hover {
    background: lighten($btn-success-bg, 5%);
  }
}