website: news: Highlight Scheme syntax.

* website/www/news.scm (%default-special-prefixes, lex-scheme/guix): New
variables.
(syntax-highlight): New procedure.
(post->sxml): Use it.
* website/static/base/css/code.css: New file.
* website/static/base/css/news.css: Import it.
* website/posts/running-services-in-containers.md: Use ```scheme for the
Scheme snippet.

1 files changed, 1 insertions, 0 deletions

diff --git a/website/static/base/css/news.css b/website/static/base/css/news.css
index f0383e2..e2c49ba 100644
--- a/website/static/base/css/news.css
+++ b/website/static/base/css/news.css
@@ -4,6 +4,7 @@
 */
 
 @import url("article.css");
+@import url("code.css");
 
 .example {
     border-style: none;