Add citation utility class and improve grid naming

- Rename layout-2col grid area 'footer' to 'buffer' for clarity
- Add .cite utility class for bottom-left citations
- Include citation examples in both demo presentations
- Document citation usage in README

1 files changed, 11 insertions, 1 deletions

diff --git a/acarp.css b/acarp.css
index 6395e52..98363d7 100644
--- a/acarp.css
+++ b/acarp.css
@@ -310,6 +310,16 @@ section p > img:only-child {
   margin: 0 auto;
 }
 
+/* Citation utility - bottom left corner */
+.cite {
+  position: absolute;
+  bottom: 30px;
+  left: var(--padding);
+  font-size: 0.7em;
+  color: #888888;
+  opacity: 0.9;
+}
+
 /* ============================================================================
    LAYOUT: title
    
@@ -377,7 +387,7 @@ section.layout-2col {
   grid-template-areas:
     "title title"
     "left right"
-    "footer footer";
+    "buffer buffer";
   gap: 2em;
   padding: 0;
   height: 100%;