fixed resizing bugs with chartjs in index.html

index.html

@@ -1217,7 +1217,7 @@
                 </div>
               </div>
               <div class="card-body">
-                <canvas class="chart" id="line-chart" style="height: 250px;"></canvas>
+                <canvas class="chart" id="line-chart" style="min-height: 250px; height: 250px; max-height: 250px; max-width: 100%;"></canvas>
               </div>
               <!-- /.card-body -->
               <div class="card-footer bg-transparent">