Position of pin and responsiveness

[eBusinessAtlantique]

Hello,
I have an issue with the positioning of the +.
If I put it in a specific place on the image in admin, on the frontend it is lower and a few pixels on the right.
It is lower by the size of the circle of the pin.
Also the image is not responsive. Height is always the same and width is changing.
Can this be adjusted in the code ?
Thanks !