Drupal 8 Custom Module Libraries
<p>I have the following 2 files in 2 different directoties in a custom module directory. </p>

<p>modules/custom/calculator</p>

<p>This is my info.yml file (calculator.info.yml)</p>

<pre><code>name: calculator
type: module
description: Calculator
core: 8.x
package: Custom
</code></pre>

<p>My css is in  the directory modules/custom/calculator/css and js in the modules/custom/calculator/js directory</p>

<p>My libaries file is this: (calculator.libraries.yml)</p>

<pre><code>base-style:
  version: VERSION
  css:
    component:
      css/wunderpage.css: {}
  js:
    js/wunderpage.js: {}
    js/jquery.matchHeight-min.js: {}
</code></pre>

<p>I also have a calculator.module file :</p>

<pre><code>&lt;?php

/**
 * @file
 * Contains calculator.module..
 */

use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Implements hook_help().
 */
function calculator_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    // Main module help for the calculator module.
    case 'help.page.calculator':
      $output = '';
      $output .= '&lt;h3&gt;' . t('About') . '&lt;/h3&gt;';
      $output .= '&lt;p&gt;' . t('Calculator') . '&lt;/p&gt;';
      return $output;

    default:
  }

  function calculator_preprocess_page(&amp;$variables) {
    $variables['#attached']['library'][] = 'calculator/base-style';
  }
}
</code></pre>

<p>Still my css and js etc is not being loaded. </p>

<p>Somebody knows why my libraries are not being loaded?</p>