Аня гений, а я просто доделал дезигн :Б

Hotel/HostrelHeadwaiterApp/Views/Home/AddDinnerToRoom.cshtml

@@ -20,8 +20,10 @@
 			<select id="dinner" name="dinner" class="form-control" asp-items="@(new SelectList(@ViewBag.Dinners, "Id", "DinnerName"))"></select>
 		</div>
 	</div>
-	<div class="u-align-right u-form-group u-form-submit u-label-top">
+
-		<div class="col-8"></div>
+			<br>
-		<div class="col-4"><input type="submit" value="Добавить участника" class="u-active-custom-color-6 u-border-none u-btn u-btn-submit u-button-style u-custom-color-1 u-hover-custom-color-2 u-btn-1" /></div>
+      <div class="u-container-layout u-container-layout-2">
-	</div>
+        <input type="submit" value="Сохранить" class="btn btn-outline-dark text-center d-flex justify-content-md-center" />
+      </div>
+
 </form>

Hotel/HostrelHeadwaiterApp/Views/Home/UpdateRoom.cshtml

@@ -41,15 +41,15 @@
                               class="form-control"/>
 						  </div>
 						  <div class="u-table u-table-responsive u-table-1">
-							  <label class="u-label u-text-custom-color-1 u-label-1">Участники конференции</label>
+							  <label class="u-label u-text-custom-color-1 u-label-1">Обеды для номеров</label>
-						  <table class="u-table-entity">
+						  <table class="table">
-		<thead class="u-custom-color-1 u-table-header u-table-header-1">
+		<thead class="thead-dark">
 			<tr style="height: 44px">
-				<th class="u-border-1 u-border-black u-table-cell">
+				<th class="u-border-1 u-border-grey-50 u-table-cell">
-					Участники
+					Обед
 				</th>
-				<th class="u-border-1 u-border-black u-table-cell">
+				<th class="u-border-1 u-border-grey-50 u-table-cell">
-					Гражданство
+					Цена
 				</th>
 			</tr>
 		</thead>