Fix wave overlay ratio

Author: steph1111

_includes/comp-showcase.html

@@ -7,5 +7,7 @@
                 </div>
             </div>
         </div>
-        <div class="wave-overlay" style="background: url('{{page.hero-overlay}}') no-repeat bottom center;"></div>
+        <div class="wave-overlay">
+            <img src="{{page.hero-overlay}}" alt="Wave Graphic">
+        </div>
 </section>