index.html: Add demo video

Not committing the video files. They're only 3 & 4 megabytes each, but
that still seems a bit too much to keep in version control.

Add the video to the home page and center it in the content area. We
give it a negative margin to center it since it's wider than the
container.

1 files changed, 4 insertions, 0 deletions

diff --git a/assets/stylesheets/layout.hcss b/assets/stylesheets/layout.hcss
index 28c1d40..e06fc88 100644
--- a/assets/stylesheets/layout.hcss
+++ b/assets/stylesheets/layout.hcss
@@ -80,6 +80,10 @@ ul {
 	margin-left: auto;
 }
 
+.margin-left-neg-12\.5\% {
+	margin-left: -12.5%;
+}
+
 .padding-top-9 {
 	padding-top: 9px;
 }