fix

src/pages/index.less

@@ -12,6 +12,7 @@
     background-color: #000;
     background-repeat: no-repeat;
     background-size: cover;
+    background-position: center;
     margin: 5rem auto 0 auto;
     border: .3125rem solid #fff;
     box-shadow: 0 0 1rem rgba(0, 0, 0, 0.5);