Google is a lot more complicated than just reading the tags inside your page. Content and user behavior during a user's stay on a website are tracked too. It doesn't matter if it's one page or multiple pages, the important thing is that the crawlers can read the contents and links of your page, which they can't, so it's not just a matter of each layout on it's own page. You want text to be text in html, and not text like games to be embedded.
If you're not familiar with html and css and are set on working this way, then do with what you've got. On the other hand, having a fully working mockup would make it very very very easy and quick for a web designer to put together the actual thing for you.
As a compromise, I believe the contents of form elements and the html element in Construct WOULD be accessible to Google, so that could be an option.