Vertically center code. Fix #108

Author: octref

webview/index.html

@@ -39,6 +39,9 @@
       width: calc(100% - 8rem);
     }
     #snippet > div {
+      display: flex;
+      flex-flow: column nowrap;
+      justify-content: center;
       max-width: 100%;
       white-space: pre-wrap !important;
       word-break: break-all;