Install WSP File from local into SharePoint Online

Hi All,

I created a sandbox solution to run in SharePoint online (solution to create new master page). I created project using my local SharePoint as site url ( because VS 2013 not allow to use remote url to create SharePoint empty project).

I try to publish it and it works normal. I already upload it to my SharePoint online and activate it. But my master page not appear in my SharePoint online. It keeps appear in my local SharePoint. So, how do i change the site url of WSP file? Or how do i need to install my sandbox solution in my SharePoint Online

Thanks