diff --git a/index.html b/index.html
index 2f51b65..2101408 100644
--- a/index.html
+++ b/index.html
@@ -21,10 +21,103 @@
         background-color: var(--color-text-3);
       }
     </style>
+    <style>
+      #loading-mask {
+        position: fixed;
+        left: 0;
+        top: 0;
+        height: 100%;
+        width: 100%;
+        background: #fff;
+        user-select: none;
+        z-index: 9999;
+        overflow: hidden;
+      }
+      .loading-wrapper {
+        position: absolute;
+        top: 50%;
+        left: 50%;
+        transform: translate(-50%, -100%);
+      }
+      .loading-dot {
+        animation: antRotate 1.2s infinite linear;
+        transform: rotate(45deg);
+        position: relative;
+        display: inline-block;
+        font-size: 64px;
+        width: 64px;
+        height: 64px;
+        box-sizing: border-box;
+      }
+      .loading-dot i {
+        width: 22px;
+        height: 22px;
+        position: absolute;
+        display: block;
+        background-color: #1890ff;
+        border-radius: 100%;
+        transform: scale(0.75);
+        transform-origin: 50% 50%;
+        opacity: 0.3;
+        animation: antSpinMove 1s infinite linear alternate;
+      }
+      .loading-dot i:nth-child(1) {
+        top: 0;
+        left: 0;
+      }
+      .loading-dot i:nth-child(2) {
+        top: 0;
+        right: 0;
+        -webkit-animation-delay: 0.4s;
+        animation-delay: 0.4s;
+      }
+      .loading-dot i:nth-child(3) {
+        right: 0;
+        bottom: 0;
+        -webkit-animation-delay: 0.8s;
+        animation-delay: 0.8s;
+      }
+      .loading-dot i:nth-child(4) {
+        bottom: 0;
+        left: 0;
+        -webkit-animation-delay: 1.2s;
+        animation-delay: 1.2s;
+      }
+      @keyframes antRotate {
+        to {
+          -webkit-transform: rotate(405deg);
+          transform: rotate(405deg);
+        }
+      }
+      @-webkit-keyframes antRotate {
+        to {
+          -webkit-transform: rotate(405deg);
+          transform: rotate(405deg);
+        }
+      }
+      @keyframes antSpinMove {
+        to {
+          opacity: 1;
+        }
+      }
+      @-webkit-keyframes antSpinMove {
+        to {
+          opacity: 1;
+        }
+      }
+    </style>
     <script src="serial.js"></script>
   </head>
   <body>
-    <div id="app"></div>
+    <div id="app">
+      <div id="loading-mask">
+        <div class="loading-wrapper">
+          <span class="loading-dot loading-dot-spin"
+            ><i></i><i></i><i></i><i></i
+          ></span>
+        </div>
+      </div>
+    </div>
     <script type="module" src="/src/main.ts"></script>
   </body>
 </html>
