Error when loading CSS files from node_modules in Angular 5

I'm trying to create a template with OnsenUI 2 and I can't load the CSS files from the node_modules folder in the .angular-cli.json file. I did this as indicated on https://onsen.io/v2/guide/angular2/#angular-2

"styles": [
          "../node_modules/onsenui/css/onsenui.css",
          "../node_modules/onsenui/css/onsen-css-components.css",
          "styles.css"
        ],

I just checked the CSS files and they do exist in this folder

Then I see this error

ERROR in ./node_modules/css-loader?{"sourceMap":false,"import":false}!./node_modules/postcss-loader/lib?{"ident":"postcss","sourceMap":false}!./node_modules/onsenui/css/onsenui.css Module build failed: Error: Can't resolve 'ionicons/css/ionicons.min.css' in 'C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\onsenui\css' at onError (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:61:15) at loggingCallbackWrapper (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\createInnerCallback.js:31:19) at runAfter (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:158:4) at innerCallback (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:146:3) at loggingCallbackWrapper (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\createInnerCallback.js:31:19) at next (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\tapable\lib\Tapable.js:252:11) at C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\UnsafeCachePlugin.js:40:4 at loggingCallbackWrapper (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\createInnerCallback.js:31:19) at runAfter (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:158:4) at innerCallback (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:146:3) at loggingCallbackWrapper (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\createInnerCallback.js:31:19) at next (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\tapable\lib\Tapable.js:252:11) at innerCallback (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\Resolver.js:144:11) at loggingCallbackWrapper (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\createInnerCallback.js:31:19) at next (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\tapable\lib\Tapable.js:249:35) at resolver.doResolve.createInnerCallback (C:\Users\mauri\Documents\GitHub\IMS_MobileApps\Demos\Demos - OnsenUI\demo1\node_modules\enhanced-resolve\lib\DescriptionFilePlugin.js:44:6) @ ./node_modules/onsenui/css/onsenui.css 4:14-119 @ multi ./node_modules/onsenui/css/onsenui.css ./node_modules/onsenui/css/onsen-css-components.css ./src/styles.css