完成上传页面结构

src/App.css

@@ -1,14 +1,20 @@
 a.btn {
   text-decoration: none;
+}
+.btn {
   color: white !important;
   border-radius: .5rem;
   padding: .375rem 1.75rem;
   font-size: 1.1rem;
 }
-a.btn:active {
+.btn:active {
   color: white !important;
 }
 
+button.btn {
+  border: none;
+}
+
 .btn-primary {
   background-color: #318ffb;
 }