Fixed paths for GitHub Pages

Update index.php, intro.php, and sidebar.php

htdocs/index.php

@@ -7,10 +7,10 @@
     <!--<meta name="viewport" content="width=device-width"/>-->
     <meta name="author" content="Herwin Bozet">
     <meta name="robots" content="index, follow">
-    <link rel="icon" type="image/svg+xml" href="/favicon.svg">
-    <link rel="alternate icon" href="/favicon.ico">
-    <link rel="stylesheet" href="/css/nibblepoker.min.css">
-    <link rel="stylesheet" href="/css/debugger.min.css">
+    <link rel="icon" type="image/svg+xml" href="./favicon.svg">
+    <link rel="alternate icon" href="./favicon.ico">
+    <link rel="stylesheet" href="./css/nibblepoker.min.css">
+    <link rel="stylesheet" href="./css/debugger.min.css">
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.6.0/css/all.min.css"
           crossorigin="anonymous"
           referrerpolicy="no-referrer" />
@@ -124,8 +124,8 @@
     </a>
 </footer>
 
-<script src="/js/sidebar.js"></script>
-<script src="/js/text-direction-switch.js"></script>
-<script src="/js/anchor-fix.js"></script>
+<script src="./js/sidebar.js"></script>
+<script src="./js/text-direction-switch.js"></script>
+<script src="./js/anchor-fix.js"></script>
 </body>
 </html>

htdocs/parts/intro.php

@@ -7,6 +7,7 @@ if(basename(__FILE__) == basename($_SERVER["SCRIPT_FILENAME"])) {
 global $root_path;
 ?>
 
+<a id="intro"></a>
 <div class="p-xs b r-s bkgd-grid">
     <h2 class="t-w-500 t-size-14">Introduction</h2>
 </div>

htdocs/parts/sidebar.php

@@ -8,9 +8,9 @@ if(basename(__FILE__) == basename($_SERVER["SCRIPT_FILENAME"])) {
 <nav id="sidebar" class="sidebar">
 
     <div class="p-m pt-l">
-        <a href="/" class="no-select">
+        <a href="#intro" class="no-select">
             <img class="logo-sidebar-v2"
-                 src="/img/logo-large-fluent-unshaded.svg"
+                 src="./img/logo-large-fluent-unshaded.svg"
                  alt="Website's logo"
                  draggable="false">
         </a>