Re-instate light/dark mode for icons

Author: insectengine

_includes/about.html

@@ -9,22 +9,26 @@ <h2>Open Source Utterly and Absolutely</h2>
       <h2>What Makes Quarkus Different?</h2>
     </div>
     <div class="width-3-12 width-12-12-m">
-      <img src="{{site.baseurl}}/assets/images/about/icon-developerjoy.svg">
+      <img class="light-only" src="{{site.baseurl}}/assets/images/about/icon-developerjoy.svg">
+      <img class="dark-only" src="{{site.baseurl}}/assets/images/about/icon-developerjoy-dark.svg">
       <h3>Developer Joy</h3>
       <p>Developers are critical to the success of almost every organization and they need the tools to build cloud-native applications quickly and efficiently. Quarkus provides a frictionless development experience through a combination of tools, libraries, extensions, and more. Quarkus makes developers more efficient with tools to improve the inner loop development cycle while in dev mode. <br><a href="/developer-joy/">Learn more about Developer Joy</a></p>
     </div>
     <div class="width-3-12 width-12-12-m">
-      <img src="{{site.baseurl}}/assets/images/about/icon-kube-native.svg">
+      <img class="light-only" src="{{site.baseurl}}/assets/images/about/icon-kube-native.svg">
+      <img class="dark-only" src="{{site.baseurl}}/assets/images/about/icon-kube-native-dark.svg">
       <h3>Kubernetes-native</h3>
       <p>Quarkus was built from the ground up for Kubernetes making it easy to deploy applications without having to understand all of the complexities of the platform. Quarkus allows developers to automatically generate Kubernetes resources including building and deploying container images without having to manually create YAML files. <br><a href="/kubernetes-native/">Learn more about Kubernetes-native</a></p>
     </div>
     <div class="width-3-12 width-12-12-m">
-      <img src="{{site.baseurl}}/assets/images/about/icon-standards.svg">
+      <img class="light-only" src="{{site.baseurl}}/assets/images/about/icon-standards.svg">
+      <img class="dark-only" src="{{site.baseurl}}/assets/images/about/icon-standards-dark.svg">
       <h3>Best of Breed Libraries and Standards</h3>
       <p>Quarkus provides a cohesive, fun to use, full-stack framework by leveraging a growing list of hundreds of best-of-breed libraries that you love and use. All wired on a standard backbone. <br><a href="/standards/">Learn more about Standards</a></p>
     </div>
     <div class="width-3-12 width-12-12-m">
-      <img src="{{site.baseurl}}/assets/images/about/icon-reactive.svg">
+      <img class="light-only" src="{{site.baseurl}}/assets/images/about/icon-reactive.svg">
+      <img class="dark-only" src="{{site.baseurl}}/assets/images/about/icon-reactive-dark.svg">
       <h3>Imperative and reactive code</h3>
       <p>Quarkus is designed to seamlessly combine the familiar imperative style code and the non-blocking, reactive style when developing applications.</p>
       <p>This is helpful for both Java developers who are used to working with the imperative model and don’t want to switch things up, and those working with a cloud-native/reactive approach. The Quarkus development model can adapt itself to whatever app you’re developing. <br><a href="/continuum/">Learn more about Reactive</a></p>