Subjunctive mood fix

docs/start/customelements.md

@@ -11,7 +11,7 @@ subtitle: Learn about the foundation of Polymer-based apps
 
 ## Introduction
 
-If HTML was reinvented tomorrow, it would provide more features and greater capability than today's built-in elements. For example, imagine you're building a photo booth app to capture snapshots, display thumbnails, and cycle through recent photos. If HTML provided the `<camera>`, `<carousel>`, or `<tabs>` element, you wouldn't think twice about using them. You'd accept the functionality and start writing markup!
+If HTML were reinvented tomorrow, it would provide more features and greater capability than today's built-in elements. For example, imagine you're building a photo booth app to capture snapshots, display thumbnails, and cycle through recent photos. If HTML provided the `<camera>`, `<carousel>`, or `<tabs>` element, you wouldn't think twice about using them. You'd accept the functionality and start writing markup!
 
 Fortunately, [Custom Elements](/platform/custom-elements.html) pave a path to {{site.project_title}}'s "[Everything is an element](/docs/start/everything.html#everythingis)" philosophy. Embracing the philosophy means a web app becomes a collection of well-defined, reusable components. You create applications by assembling custom elements: either ones provided by {{site.project_title}}, [ones you create](/docs/start/creatingelements.html) yourself, or third-party elements.