Added stuff.

index.php

@@ -1 +1,33 @@
-<?php echo "hi" ?>
+<?php
+
+$sites = file("sites.txt", FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
+
+$current = $_GET['site'] ?? '';
+
+if (!$current) {
+    echo "No site specified.";
+    exit;
+}
+
+$index = array_search($current, $sites);
+
+if ($index === false) {
+    echo "Site not in ring.";
+    exit;
+}
+
+$total = count($sites);
+
+$prevIndex = ($index - 1 + $total) % $total;
+$nextIndex = ($index + 1) % $total;
+
+$prev = $sites[$prevIndex];
+$next = $sites[$nextIndex];
+
+?>
+
+<div class="webring">
+    <a href="<?= htmlspecialchars($prev) ?>">← Previous</a>
+    |
+    <a href="<?= htmlspecialchars($next) ?>">Next →</a>
+</div>