fix: interface fixes

lib/pages/main.dart

@@ -270,12 +270,12 @@ class _MainPageState extends State<MainPage> {
                                     SliverGridDelegateWithFixedCrossAxisCount(
                                         crossAxisCount: min(
                                             (MediaQuery.sizeOf(context).width ~/
-                                                    200)
+                                                    220)
                                                 .toInt(),
                                             8),
                                         childAspectRatio: 0.8,
                                         mainAxisSpacing: 10.0,
-                                        crossAxisSpacing: 40.0),
+                                        crossAxisSpacing: 20.0),
                                 itemCount: itemViewCount,
                                 itemBuilder: (context, index) {
                                   final product = filteredData[index];

lib/pages/order_history.dart

@@ -151,7 +151,8 @@ class _HistoryPageState extends State<HistoryPage> {
                                           final item = my_orders[index];
                                           return HistoryItemCard(
                                             id: item.id,
-                                            cost: item.sum,
+                                            cost: double.parse(item.sum)
+                                                .toStringAsFixed(2),
                                             date: item.date,
                                             image: FutureBuilder(
                                               future: precacheImage(

lib/pages/order_info.dart

@@ -206,7 +206,8 @@ class _OrderInfoPageState extends State<OrderInfoPage> {
                                 crossAxisAlignment: CrossAxisAlignment.start,
                                 children: [
                                   MarkdownBody(
-                                      data: '## Итого: ${detail!.sum} руб.'),
+                                      data:
+                                          '## Итого: ${double.parse(detail!.sum).toStringAsFixed(2)} руб.'),
                                   MarkdownBody(
                                       data:
                                           "### Адрес получателя: __${detail!.address}__"),