Add indications for hyperlinks to external websites.

portfolio/css/custom.css

@@ -2,6 +2,10 @@
   font-size: 0.8rem;
 }
 
+a.external::after {
+  content: " ↗";
+}
+
 footer {
   font-size: 0.7rem;
   text-align: center;

portfolio/templates/model-kits.html

@@ -9,7 +9,7 @@
               <p class="card-text">
                 $model_name$ <span class="badge rounded-pill text-bg-secondary ms-4">$scale$</span><br/>
                 Series: $series$<br/>
-                $manufacturer$, $release$ - <a href="https://www.scalemates.com/search.php?fkSECTION%5B%5D=All&q=$number$*">$number$</a><br/>
+                $manufacturer$, $release$ - <a class="external" aria-label="scalemates dot com (opens external site in new tab)" href="https://www.scalemates.com/search.php?fkSECTION%5B%5D=All&q=$number$*" target="_blank" rel="noopener noreferrer">$number$</a><br/>
                 Bought at $purchase_store$ for $price$ <em>($purchase_date$)</em><br/>
               </p>
               <p class="card-text"><em class="text-body-secondary">$date$</em></p>