You’re using a CSS minifier plugin so I can’t tell exactly which line it’s coming from since the CSS is all mixed in together. If you temporarily deactivate the CSS minifier plugin then I can tell you the exact line you’ll need to adjust.
Other than that, if you search for this in your style.css file, you’ll see the part you’ll need to change –
.site-inner {
background-color: #fff;
clear: both;
margin-top: 170px;
position: relative;
z-index: 9;
-word-wrap: break-word;
}
You can also add in your own Custom CSS inside the Customizer page (use the Additional CSS tab/page) and add this –
.site-inner {
margin-top: 300px;
}
When you add in the code, make sure and click your Reload button on your Browser so it instantly clears your Browser Cache….which means you’ll see the latest changes to your CSS file show up immediately.
Let me know if that helps or if you need assistance.