tweak user card on dashboard

lib/dagon_web/templates/dashboard/index.html.eex

@@ -1,5 +1,5 @@
-<div class="columns has-margin-top">
-	<div class="column is-one-quarter">
+<div class="columns has-margin-top is-desktop">
+	<div class="column is-half is-one-third-desktop">
 		<div class="card">
 			<div class="card-content">
 				<div class="media">