Question

Iam new here and new in coding.
I want a background attachment to be placed in a very certain position
top,top left,top right etc won’t do the job, I want a most accurate position
eg. the attachments upleft corner to be placed in 100,200

Answer 1

If you want it to be done in CSS then go for this

div
{
    background-image:url('your-img-url');
    background-repeat:no-repeat;
    background-position:100px 200px;
    background-attachment:fixed;
}