As previously mentioned, you need to add the tilde when you're importing inside your css.
@import 'bootstrap/scss/bootstrap.scss';
Second, the bootstrap css file is loading fonts along with the stylesheet, resulting in the error you're having because it's using relatives paths webpack doesn't know where to pickup.
To fix that, you could either change the path of the folder to the correct one like the following as seen from here:
$icon-font-path: "~bootstrap-sass/assets/fonts/bootstrap";
@import "~bootstrap-sass/assets/stylesheets/bootstrap";
And add the fonts loader to your webpack configuration:
{
test: /\.(eot|svg|ttf|woff|woff2)$/,
loader: 'url-loader',
}
But the easiest way for you to get around the problem would be to remove the style import you are doing, remove the bootstrap-sass
dependency and use the cdn instead.
@import url('https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css');
The advantage of doing this is that clients that have already downloaded bootstrap using this cdn will get the cached version. Since a lot of websites theses days use it, It's very likely they won't have to download it again, and it also saves you the trouble of hosting it or incorporating into your bundle.