Image Post Page is Pushing Image into Header

I can see this style in your style.css

/* Singular */
.singular #primary {
	margin: 0;
margin-top: -1150px;
}

But it’s also a twenty eleven theme. so you should first create a child theme, and then add this code to it’t style.css

.singular #primary{
margin-top:0;
}

Thanks for your help! Do I need any specific code in that child theme style.css file? Can I just copy and paste a template from my twenty eleven style.css and add that piece of code?

child theme style.css needs to have that commented code at the very top of the file(the one with author, title of child theme, title of parent theme…) and there you just have to add that piece of code i gave you. Hope that works for you. ??

thanks so much for your help!!