Add smooth value to image-rendering property (#2883)

Author: skyclouds2001

live-examples/css-examples/images/image-rendering.html

@@ -6,6 +6,13 @@
     </button>
   </div>
 
+  <div class="example-choice">
+    <pre><code class="language-css">image-rendering: smooth;</code></pre>
+    <button type="button" class="copy hidden" aria-hidden="true">
+      <span class="visually-hidden">Copy to Clipboard</span>
+    </button>
+  </div>
+
   <div class="example-choice">
     <pre><code class="language-css">image-rendering: crisp-edges;</code></pre>
     <button type="button" class="copy hidden" aria-hidden="true">