Fix issues in preload state

gulp/preloader.css

@@ -59,7 +59,7 @@ body {
 #ll_p {
     display: grid;
     position: fixed;
-    z-index: 99999;
+    z-index: 999;
     top: 0;
     left: 0;
     right: 0;

src/css/states/preload.scss

@@ -1,11 +1,4 @@
 #state_PreloadState {
-    &.failure {
-        .loadingImage,
-        .loadingStatus {
-            display: none;
-        }
-    }
-
     .changelogDialogEntry {
         @include S(margin-top, 10px);
 
@@ -54,6 +47,18 @@
     }
 
     .failureBox {
+        position: absolute;
+        top: 0;
+        left: 0;
+        right: 0;
+        bottom: 0;
+        z-index: 999999;
+        background: #d5d8de;
+        display: flex;
+        align-items: center;
+        justify-content: center;
+        flex-direction: column;
+
         .logo {
             img {
                 @include S(width, 240px);

src/js/states/preload.js

@@ -16,17 +16,6 @@ export class PreloadState extends GameState {
         super("PreloadState");
     }
 
-    getInnerHTML() {
-        return `
-            <div class="loadingImage"></div>
-            <div class="loadingStatus">
-                <span class="desc">${G_CHINA_VERSION || G_WEGAME_VERSION ? "加载中" : "Booting"}</span>
-                </div>
-            </div>
-            <span class="prefab_GameHint"></span>
-        `;
-    }
-
     getThemeMusic() {
         return null;
     }