Full page-width image

I have set all of the margins and padding to zero in an attempt to create a full page-wide image at the top of the page.  On my computer ( 2017 Macbook Air with screen width of 1440px), the image fills the screen and looks great, but I am able to scroll a bit to the right of the page and see a white side stripe.  On computers with a larger screen with, the image no longer fills the entire screen width, there are instead white margins on eat side despite this CSS code: body{width:100%;margin:auto;min-width:600px;max-width:3000px} (The 3000px should accomodate for most larger monitors and laptops).  Is there a reason this is happening, and are there any better ways to achieve the full-width image look?

Thank you!

25 minutes ago, SquarespaceUser3 said:

I have set all of the margins and padding to zero in an attempt to create a full page-wide image at the top of the page.  On my computer ( 2017 Macbook Air with screen width of 1440px), the image fills the screen and looks great, but I am able to scroll a bit to the right of the page and see a white side stripe.  On computers with a larger screen with, the image no longer fills the entire screen width, there are instead white margins on eat side despite this CSS code: body{width:100%;margin:auto;min-width:600px;max-width:3000px} (The 3000px should accomodate for most larger monitors and laptops).  Is there a reason this is happening, and are there any better ways to achieve the full-width image look?

Thank you!

You can try using the vw and vh unit, 100vw mean 100% actual screen width, same with vh for height