Theft Description

I got home at around 16:00 and folded the bike, I put it by my front door. Then I got distracted with some mail that I had received and with some messages I needed to send related to the mail I received. I closed the door and forgot for a moment about the bike, When I remembered that I left it outside I went to get it and it was not there. My front door has a wall where the bins are located, it was not on the street. Whoever took it clearly knows that it belongs to people who live at this address. I saw a shape outside but I thought the person was just passing by, I believe this person took it but I am unable to describe it as one cannot see through the window or glass.