This one is rather easy. You do not have a description meta-tag. Search engine result page (SERP) snippets generally come from the description meta-tag though another closer matching content snippet can be used instead to satisfy the searchers intent.
While the site does look good, you have made some fundamental SEO mistakes.
title tag is too simplistic. It does not include the top 2-3 most important keywords for your site.
Title tags should not be over 50 characters. The actual limit is 512 pixels where wider characters such as Q, W, M, G, and so on will limit the actual number of characters. The range you want to hit is 45-50 characters keeping it to less than 512 pixels.
You are missing a
description meta-tag. This should contain the top 2-3 most important keywords plus a few more that searchers will likely use to find your site. This is crucial. While it is argued that
description meta-tag keywords do not carry much weight, it is absolutely true that keyword matches are made against the
description meta-tag likely more times than most tags.
You are also missing an
h1 tag. This is important. The
h1 tag supports the
title tag and should contain the top 2-3 most important keywords for your site and should not be a duplicate of the
title tag though it can be somewhat similar.
You are not using other header tags (
h4, ...) These are important to contain the other more important keywords for your site.
Without these elements, this site can never rank.
As well, the single page design is terrible for SEO unless it can appear as several real pages to the search engine. In this case, you will want to use parameters that make each relative page of content look like a separate page. The reason is simple. Search engines still favor old-school pages of content.
This does not mean that a one page site cannot rank. It can.
However, search engines will not effectively index your site. I did a site: search against your domain name and only one SERP listing comes up.
Lastly, search engines like sites that have content. This is no secret these days. You are far better off creating helpful content to attract users and using carefully selected keywords for each page to cover the topic spectrum. We can discuss this at another time when you get to that point.