Restore custom CSS version and fixed version

HTML_Custom_Dir has been added to take the custom CSS file, but it is not
used by my gnatdoc version.

asfml.gpr

@@ -101,6 +101,7 @@ library project ASFML is
     for Custom_Tags_Definition use "tools/sfml-doc-tags.py";
     --  GNATdoc loads provided file on startup to process custom tags
     for Image_Dir use "images";
+    for HTML_Custom_Dir use "tools/gnatdoc_html";
   end Documentation;
 
 end ASFML;

doc/gnatdoc.css

@@ -46,15 +46,15 @@ td {
     width: 30%;
 
     overflow: auto;
-    background-color: #111;
+    background-color: #2f3237;
 }
 
 #toc p.projectName {
     margin-top: 20px;
     margin-left: 20px;
     margin-bottom: 0;
     color: #bbb;
-    font-size: 150%;
+    font-size: 400%;
 }
 
 #toc p.documentationTimestamp {
@@ -85,7 +85,9 @@ td {
 }
 
 #tocMenu li.current {
-    background-color: #222;
+    background-color: #155799;
+    border-bottom-left-radius: 5px;
+    border-top-left-radius: 5px;
 }
 
 #tocMenu a {
@@ -104,7 +106,11 @@ td {
     color: #bbb;
     font-weight: 300;
     display: inline-block;
-    background-color: #222;
+    background-color: #155799;
+    padding-top: 10px;
+    padding-bottom: 10px;
+    border-bottom-left-radius: 5px;
+    border-top-left-radius: 5px;
 }
 
 #tocView ul {
@@ -135,7 +141,7 @@ td {
 }
 
 #tocView li a:hover {
-    background-color: #111;
+    background-color: #2f3237;
 }
 
 #tocView h1,
@@ -244,7 +250,7 @@ h2 {
 }
 
 #body h2 {
-    text-transform: uppercase;
+    font-weight: bold;
     padding: 20px 0 15px 0;
 }
 

doc/index.js

@@ -1,4 +1,4 @@
 GNATdoc.Index = {
   "project": "ASFML",
-  "timestamp": "2022-08-09 14:04:03"
+  "timestamp": "2022-08-09 17:29:16"
 };

doc/srcs/sf.ads.js

@@ -899,7 +899,7 @@ GNATdoc.SourceFile = {
         {
           "kind": "span",
           "cssClass": "number",
-          "text": "2"
+          "text": "3"
         },
         {
           "kind": "span",