Changed button color in web tool

Author: stephenchouca

_includes/demo.html

@@ -42,7 +42,7 @@ <h6 style="margin-bottom: 0px; margin-top: 18px">Input a tensor algebra expressi
           <input id="prefix" class="mdl-textfield__input" style="font-family: monospace" spellcheck="false" autocomplete="off" autocorrect="false" autocapitalize="false">
           <label class="mdl-textfield__label">Prefix (Optional)</label>
         </div>
-        <button id="btnGetKernel" class="button demo-btn">Generate Kernel</button>
+        <button id="btnGetKernel" class="button is-primary demo-btn">Generate Kernel</button>
       </div>
     </div>
   </div>
@@ -119,10 +119,10 @@ <h6 style="margin-bottom: 0px; margin-top: 18px">Input a tensor algebra expressi
 <div class="mdl-grid" style="padding-top: 8px; padding-bottom: 0px">
   <div class="mdl-cell mdl-cell--12-col">
     <div align="right" style="padding-right: 0px">
-      <button id="btnCPU" class="button sample-button">
+      <button id="btnCPU" class="button is-primary sample-button">
         Sample CPU Schedule
       </button>
-      <button id="btnGPU" class="button sample-button">
+      <button id="btnGPU" class="button is-primary sample-button">
         Sample GPU Schedule
       </button>
     </div>
@@ -166,7 +166,7 @@ <h6 style="margin-bottom: 0px; margin-top: 18px">Input a tensor algebra expressi
             </div>
           </td>
           <td id="cellBtnDownload" align="right">
-            <button id="btnDownload" class="button" style="width: 100%">Download</button>
+            <button id="btnDownload" class="button is-primary" style="width: 100%">Download</button>
           </td>
         </tr>
       </table>

javascripts/demo.js

@@ -829,7 +829,7 @@ function demo() {
         var reorderId = "reorder" + row;
         parameters += "<li class=\"add-reorder\" id=\"";
         parameters += reorderId;
-        parameters += "\"><button class=\"button\" style=\"width: 200px; ";
+        parameters += "\"><button class=\"button is-primary\" style=\"width: 200px; ";
         parameters += "margin-top: 13.5px\">Add IndexVar</button></li>";
       }