feat: Update homepage announcement and community images

less/page_css_file/homepage.less

@@ -406,7 +406,10 @@
             width: 100%;
             height: 100%;
             object-fit: cover;
-            filter: grayscale(100%);
+
+            @media (min-width: @screen-sm-min) {
+                position: absolute;
+            } 
         }
     }