update css

static/css/style.css

@@ -1068,6 +1068,12 @@
     image-rendering: -webkit-optimize-contrast;
 }
 
+@media (max-width: 991px) {
+    .blog-traffic .add-img {
+        margin: 0 auto;
+    }
+}
+
 @media (max-width: 767px) {
     .blog-traffic .add-img {
         margin: 10px auto -25px;