add v3 demands

app.vue

@@ -9,14 +9,47 @@ body {
   line-height: 1.6;
   font-size: 18px;
   color: #444;
+  background-color: #efefef;
   padding: 0 10px;
   font-family: 'Arial'
 }
 
+main,
+form {
+  display: flex;
+  flex-wrap: none;
+  flex-direction: column;
+}
+
 h1,
 h2,
 h3 {
   line-height: 1.2;
   text-decoration: underline;
 }
+
+img {
+  max-width: 100%;
+  margin-top: 1em;
+  margin-bottom: 1em;
+
+}
+
+button {
+  cursor: pointer;
+  margin-top: 1em;
+  margin-bottom: 1em;
+  padding: .375rem .75rem;
+  border-width: 0px;
+  border-radius: .5em;
+  background-color: rgb(17, 95, 239);
+  color: white;
+  font-size: 1em;
+  width: 100%;
+}
+
+button:disabled {
+  cursor: not-allowed;
+  filter: grayscale(100%);
+}
 </style>