fix(css): improve wrapping when right sidebar has more than two items (#762)

* improve wrapping when right sidebar has more than two items, particularly on mobile

* Adjusted min-width

quartz/styles/base.scss

@@ -171,9 +171,11 @@ a {
 
     & .sidebar.right {
       right: calc(calc(100vw - $pageWidth) / 2 - $sidePanelWidth);
+      flex-wrap: wrap;
       & > * {
         @media all and (max-width: $fullPageWidth) {
           flex: 1;
+          min-width: 140px;
         }
       }
     }