减少切换按钮的延迟，进入页面就读取全按钮

src/components/Cards.vue

@@ -229,6 +229,7 @@ export default {
         this.init(lang)
     },
     mounted: function () {
+        this.preloadTabImages();
         this.init2();
     },
     data() {
@@ -297,10 +298,20 @@ export default {
             this.activeTab = tab;
             $(".input-sm").attr("placeholder", placeholder[tab]);
         },
+        preloadTabImages() {
+            const imgs = []
+            Object.values(this.tabImages).forEach(({A, B}) => {
+            [A, B].forEach(src => {
+                const im = new Image()
+                im.src = src
+                imgs.push(im)
+            })
+            })
+            // Keep a reference so GC doesn’t drop them immediately
+            this._preloaded = imgs
+        },
         getTabImage(tab) {
-            return this.activeTab === tab
-            ? this.tabImages[tab].B
-            : this.tabImages[tab].A;
+            return this.activeTab === tab ? this.tabImages[tab].B : this.tabImages[tab].A
         },
 
         init: function (lang) {