Improves upload button for files (#3044)

* reorders form, removes header

* adds flexbox + button formatting

* adjusts whitespace & flexbox class

* adjusts class for mobile

BTCPayServer/Views/Server/Files.cshtml

@@ -8,7 +8,7 @@
 @if (!Model.StorageConfigured)
 {
     <p>
-        Before being able to upload you first need to 
+        Before being able to upload you first need to
         <a asp-action="storage" asp-route-forceChoice="true" asp-route-returnurl="@ViewData["ReturnUrl"]">
             choose your file storage service provider
         </a>.
@@ -26,6 +26,16 @@ else
         </a>
     </p>
 
+    @if (Model.StorageConfigured)
+    {
+        <form asp-action="CreateFiles" method="post" enctype="multipart/form-data">
+            <div class="d-flex">
+                <input multiple type="file" class="form-control mb-3" name="files" id="files" required>
+                <button class="btn btn-primary mb-3 ms-3" role="button">Upload</button>
+            </div>
+        </form>
+    }
+
     @if (Model.Files.Any())
     {
         <table class="table table-hover table-responsive-md">
@@ -62,8 +72,7 @@ else
     }
 }
 
-
-@if(Model.DirectUrlByFiles!=null && Model.DirectUrlByFiles.Count > 0)
+@if (Model.DirectUrlByFiles != null && Model.DirectUrlByFiles.Count > 0)
 {
     foreach (KeyValuePair<string, string> fileUrlPair in Model.DirectUrlByFiles)
     {
@@ -71,7 +80,6 @@ else
         var fileUrl = fileUrlPair.Value;
         var file = Model.Files.Single(storedFile => storedFile.Id.Equals(fileId, StringComparison.InvariantCultureIgnoreCase));
 
-
         <div class="card mb-2">
             <div class="card-text">
                 <ul class="list-group list-group-flush">
@@ -97,11 +105,3 @@ else
     }
 }
 
-@if (Model.StorageConfigured)
-{
-<form asp-action="CreateFiles" method="post" enctype="multipart/form-data">
-    <h4 class="mt-5 mb-3">Upload Files</h4>
-    <input multiple type="file" class="form-control mb-3" name="files" id="files" required>
-    <button class="btn btn-primary" role="button"><span class="fa fa-plus"></span> Upload files</button>
-</form>
-}