fix: properly defined parameters for the URL function

Related: #21

src/QUI/ERP/Order/SimpleCheckout/Checkout.css

@@ -157,12 +157,10 @@
     border: none;
 }
 
-.quiqqer-simple-checkout-basket__link {
-    font-size: 12px;
-    text-align: right;
+:where(.quiqqer-simple-checkout-basket__link) {
+    margin-top: 0.75rem;
+    display: inline-block;
     float: right;
-    margin-top: 10px;
-    margin-right: 10px;
 }
 
 /**************************/

src/QUI/ERP/Order/SimpleCheckout/Checkout.html

@@ -117,7 +117,7 @@
                 </button>
 
                 {if $this->getAttribute('showBasketLink') && $BasketSite}
-                    <a href="{url Site=$BasketSite}" class="quiqqer-simple-checkout-basket__link">
+                    <a href="{url site=$BasketSite}" class="quiqqer-simple-checkout-basket__link">
                         {locale group="quiqqer/order" var="ordering.btn.backToBasket"}
                     </a>
                 {/if}