Add tooltips to show what companies sponsor

Author: yasulab

app/views/custom_widget/show.html.erb

@@ -113,15 +113,28 @@
 <div id="sponsors">
   <section class='detail-introduction sponsors_logo text-center'>
     <h2>スポンサー</h2>
+    <script type="text/javascript">
+    $(function () {
+      $('[data-toggle="tooltip"]').tooltip();
+    })
+    </script>
     <ul>
-      <li><a href="https://case-shinjuku.com/">
-          <%= image_tag "logos/case-shinjuku.png"%></a></li>
-      <li><a href="http://www.osscafe.net/">
-          <%= image_tag "logos/osscafe.png"%></a></li>
-      <li><a href="https://scrivito.com/">
-	  <%= image_tag "logos/scrivito.png"%></a></li>
-      <li><a href="https://yasslab.jp/">
-          <%= image_tag "logos/yasslab.png"%></a></li>
+      <li><%= link_to image_tag('logos/case-shinjuku.png', alt: 'CASE Shinjuku',
+			    data: { toggle: 'tooltip', placement: 'bottom' },
+			    title: 'オフィス提供'),
+	      'https://case-shinjuku.com/' %></li>
+      <li><%= link_to image_tag("logos/osscafe.png", alt: "下北沢オープンソースCafe",
+			    data: { toggle: 'tooltip', placement: 'bottom' },
+			    title: 'ドメイン代の支援'),
+	      'http://www.osscafe.net/' %></li>
+      <li><%= link_to image_tag('logos/scrivito.png', alt: 'Scrivito',
+			    data: { toggle: 'tooltip', placement: 'bottom' },
+			    title: 'Cloud-Based CMS の提供'),
+	      'https://scrivito.com/' %></li>
+      <li><%= link_to image_tag('logos/yasslab.png', alt: 'YassLab',
+			    data: { toggle: 'tooltip', placement: 'bottom' },
+			    title: 'Web開発およびDNS代の支援'),
+	      'https://yasslab.jp/' %></li>
     </ul>
   </section>
 </div>