function edit_record_form($id) {
  global $conn;

  $stmt = $conn->prepare("SELECT barva FROM barvy WHERE id = ?");
  $stmt->execute([$id]);
  $row = $stmt->fetch();
  $barva = $row ? $row['barva'] : '';

  echo '<form>
        <label for="color">Nová barva:</label>
        <input type="text" id="color" name="color" value="'.$barva.'">
        
        <input type="hidden" name="id" value="'.$id.'">
        <input type="hidden" name="action" value="update">
        
        <br><br>
        <input type="submit" value="Upravit">
        </form>';
        }