fix: change imageblock, can apply invert without affecting shadows

The problem was that if we tried to apply invert to invert to
colors of svg in dark mode that the shadows were also inverted.
By changing the css this way we keep the old style with the added
benefit of being to apply invert on the img tag

assets/css/main.css

@@ -51,6 +51,12 @@
     .prose :where(code):not(:where([class~="not-prose"] *)) {
         @apply bg-gray-300 dark:bg-gray-900 dark:text-gray-300 text-gray-800 py-1 px-2 rounded font-normal;
     }
+
+    .sect1 + #footnotes {
+        hr {
+            @apply hidden;
+        }
+    }
 }
 
 @layer components {
@@ -74,15 +80,16 @@
     }
 
     .imageblock {
-        @apply px-4 my-2;
+        @apply px-4 my-2 flex justify-center flex-col;
         &.thumb{
             @apply lg:max-w-md md:max-w-sm sm:max-w-full;
         }
 
         .content{
+            @apply my-1 shadow-md dark:shadow-slate-900 mx-auto;
 
             img {
-                @apply my-1 shadow-md dark:shadow-slate-900 mx-auto;
+                @apply m-0;
             }
         }