Index: src/wp-admin/css/forms.css
===================================================================
--- src/wp-admin/css/forms.css	(revision 29219)
+++ src/wp-admin/css/forms.css	(working copy)
@@ -751,9 +751,55 @@
 	margin: -3px 3px;
 }
 
+/*------------------------------------------------------------------------------
+21.0 - Upload File
+------------------------------------------------------------------------------*/
+
+.wp-upload-container {
+	-webkit-box-sizing: border-box;
+	-moz-box-sizing: border-box;
+	box-sizing: border-box;
+	margin: 0px 0 0;
+	padding: 0;
+	width: 100%;
+	overflow: hidden;
+	position: relative;
+	top: 10px;
+}
+.wp-upload-container-hidden {
+	display: none;
+}
+.wp-upload-container .wp-upload-form {
+	background: #fafafa;
+	border: 1px solid #e5e5e5;
+	padding: 30px;
+	margin: 30px auto;
+	max-width: 380px;
+}
+.wp-upload-container .install-help {
+	color: #999;
+	font-size: 18px;
+	font-style: normal;
+	margin: 0;
+	padding: 40px 0 0;
+	text-align: center;
+}
+
 /* =Media Queries
 -------------------------------------------------------------- */
 
+@media only screen and (max-width: 1120px) {
+	.wp-upload-container .wp-upload-form {
+		margin: 20px 0;
+		max-width: 100%;
+	}
+	.wp-upload-container .install-help {
+		font-size: 15px;
+		padding: 20px 0 0;
+		text-align: left;
+	}
+}
+
 @media screen and ( max-width: 782px ) {
 	/* Input Elements */
 	textarea {
Index: src/wp-admin/includes/plugin-install.php
===================================================================
--- src/wp-admin/includes/plugin-install.php	(revision 29219)
+++ src/wp-admin/includes/plugin-install.php	(working copy)
@@ -194,16 +194,17 @@
  *
  * @param string $page
  */
-function install_plugins_upload( $page = 1 ) {
+function install_plugins_upload() {
 ?>
-	<h4><?php _e('Install a plugin in .zip format'); ?></h4>
-	<p class="install-help"><?php _e('If you have a plugin in a .zip format, you may install it by uploading it here.'); ?></p>
-	<form method="post" enctype="multipart/form-data" class="wp-upload-form" action="<?php echo self_admin_url('update.php?action=upload-plugin'); ?>">
-		<?php wp_nonce_field( 'plugin-upload'); ?>
-		<label class="screen-reader-text" for="pluginzip"><?php _e('Plugin zip file'); ?></label>
-		<input type="file" id="pluginzip" name="pluginzip" />
-		<?php submit_button( __( 'Install Now' ), 'button', 'install-plugin-submit', false ); ?>
-	</form>
+	<div class="wp-upload-container">
+		<p class="install-help"><?php _e( 'If you have a plugin in a .zip format, you may install it by uploading it here.' ); ?></p>
+		<form method="post" enctype="multipart/form-data" class="wp-upload-form" action="<?php echo self_admin_url( 'update.php?action=upload-plugin' ); ?>">
+			<?php wp_nonce_field( 'plugin-upload' ); ?>
+			<label class="screen-reader-text" for="pluginzip"><?php _e( 'Plugin zip file' ); ?></label>
+			<input type="file" id="pluginzip" name="pluginzip" />
+			<?php submit_button( __( 'Install Now' ), 'button', 'install-plugin-submit', false ); ?>
+		</form>
+	</div>
 <?php
 }
 add_action('install_plugins_upload', 'install_plugins_upload', 10, 1);