Fix auto check user sync and CSS issue.

Author: iamdharmesh

assets/css/admin.css

@@ -47,7 +47,8 @@ table.mc-widefat, .mailchimp-sf-user-sync-page table.form-table {
 }
 
 .mailchimp-sf-user-sync-page table.form-table {
-	display: block;
+	border-collapse: separate;
+	border-spacing: 0px;
 }
 
 .mailchimp-sf-user-sync-page table.form-table tr:first-child,

includes/admin/class-mailchimp-user-sync.php

@@ -204,9 +204,9 @@ public function get_user_sync_settings( $key = null ) {
 	 */
 	public function sanitize_user_sync_settings( $new_settings ) {
 		$settings                           = $this->get_user_sync_settings();
-		$settings['enable_user_sync']       = isset( $new_settings['enable_user_sync'] ) ? 1 : 0;
+		$settings['enable_user_sync']       = ( isset( $new_settings['enable_user_sync'] ) && 1 === absint( $new_settings['enable_user_sync'] ) ) ? 1 : 0;
 		$settings['user_roles']             = isset( $new_settings['user_roles'] ) ? array_map( 'sanitize_text_field', $new_settings['user_roles'] ) : array();
-		$settings['existing_contacts_only'] = isset( $new_settings['existing_contacts_only'] ) ? 1 : 0;
+		$settings['existing_contacts_only'] = ( isset( $new_settings['existing_contacts_only'] ) && 1 === absint( $new_settings['existing_contacts_only'] ) ) ? 1 : 0;
 		$settings['subscriber_status']      = isset( $new_settings['subscriber_status'] ) ? sanitize_text_field( $new_settings['subscriber_status'] ) : 'pending';
 
 		return $settings;