style tweaks. always load sh_bright. overflow on pre only if needed. black pre background in dark mode.

static/css/style.css

-@import "sh_bright.min.css" (prefers-color-scheme: light);
+@import "sh_bright.min.css";
 @import "sh_darkness.min.css" (prefers-color-scheme: dark);
 
 body {
 
 pre {
     max-height: 300px;
-    overflow: scroll;
+    overflow: auto;
     font-size: 0.9em;
     padding: 10px;
     margin: 1em;
     #footer, #footer a:link, #footer a:visited {
         color: #B0B0B0;
     }
+
+    pre {
+        background-color: #000000;
+    }
 }