Here is a diff of the dark mode started by Omar.  The diff below
results in some differences from the screenshots I sent in the matrix
chat.  I ended up removing the borders on the footer and opted for
lines to separate each project.

diff /home/kyle/src/got
commit - 2bde3e78a5bd6619af838df19eec530e23783c0b
path + /home/kyle/src/got
blob - 67b8328cafa8a92842599b49698d625a536119bd
file + gotwebd/files/htdocs/gotwebd/gotweb.css
--- gotwebd/files/htdocs/gotwebd/gotweb.css
+++ gotwebd/files/htdocs/gotwebd/gotweb.css
@@ -459,3 +459,101 @@ dd {
     padding-bottom: 5px;
     padding-left: 10px;
 }
+
+/* dark theme */
+@media (prefers-color-scheme: dark) {
+    body {
+        color: #eee;
+        background-color: #282A36;
+    }
+
+    #index_header, #summary_wrapper, #diff_header_wrapper,
+    #blame_header_wrapper, #tree_header {
+        background-color:#BD93F9;
+        color: #222;
+    }
+
+    .commits_header_wrapper {
+        background-color:#BD93F9;
+        color: #222;
+    }
+
+    #got_link {
+        filter: brightness(0) saturate(100%)
+            invert(68%) sepia(73%) saturate(2771%)
+            hue-rotate(213deg) brightness(104%)
+            contrast(95%);
+    }
+
+    #header {
+        background-image: unset;
+    }
+
+    .index_project a {
+        color: #8BE9FD;
+        text-decoration: none;
+    }
+    .index_project a:hover {
+        color: #FFFFA5;
+        text-decoration: none;
+    }
+
+    .index_wrapper {
+        border-bottom-style: solid;
+        border-bottom-width: 1px;
+        border-image: linear-gradient(90deg, #FF79C6, #BD93F9 50%) 1;
+    }
+
+    a {
+        color: #FF79C6;
+    }
+
+    .diff_minus, .diff_submodule {
+        color: #FF5555;
+    }
+    .diff_plus, .diff_symlink, .diff_author {
+        color: #50FA7B;
+    }
+    .diff_chunk_header, .diff_date {
+        background-color: unset;
+        color: #FFB86C;
+    }
+    .diff_meta, .diff_executable, .diff_commit {
+        color: #6272A4;
+    }
+
+    .blame_code {
+        color: #eee;
+    }
+
+    .blame_wrapper {
+        color: #6272A4;
+    }
+
+    .blame_author {
+        color: #8BE9FD;
+        text-decoration: none;
+    }
+
+    #site_owner_wrapper, #np_wrapper {
+        background-color: unset;
+    }
+
+    .page_header_wrapper {
+        background-color: unset;
+    }
+
+    .navs_wrapper {
+        background-color: #282A36;
+    }
+
+    .tree_wrapper:nth-child(even) {
+        background-color: #282A36;
+    }
+
+    .tree_wrapper:nth-child(odd) {
+        background-color: #3e3e3e;
+    }
+
+}
+