some css changes

app/templates/partials/search-bar.php

@@ -0,0 +1,22 @@
+<?php
+// search-bar.php — shared search bar partial
+// $searchValue: current search query (optional)
+$_sbValue = $searchBarValue ?? $_GET['query'] ?? '';
+?>
+<form method="GET" action="/search"
+      role="search" aria-label="Recherche">
+    <label for="site-search-input" class="sr-only">Recherche</label>
+    <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"
+         fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"
+         aria-hidden="true" focusable="false">
+        <circle cx="11" cy="11" r="8"/><line x1="21" y1="21" x2="16.65" y2="16.65"/>
+    </svg>
+    <input
+        id="site-search-input"
+        type="text"
+        name="query"
+        placeholder="Recherche..."
+        value="<?= htmlspecialchars($_sbValue) ?>"
+        autocomplete="off"
+    >
+</form>