Constrain snake in parent DIV?

[alessioscand]

Hello,
thank you so much for this awesome script. It is possible to constrain the snake movement inside the parent DIV?
Thank you so much!

[oliveratgithub]

I tried that once, but didn't get it to work properly - always had a problem that the widths & heights which were somewhat off...

But here's what I tried then:

1. not creating a new div but selecting your own parent div:

//snake._el_container = document.createElement('div');
snake._el_container = document.getElementById('my-snake-div');
//document.body.appendChild(snake._el_container);
snake._el_container.style.overflow = "hidden";

2. Also attaching the "food" target to my DIV, not the HTML body

//document = document.appendChild(target);
snake._el_container.appendChild(target)

3. Then changing all "window." and height/width references to use my Div

//… = window.innerHeight
… = snake._el_container.clientHeight

//… = window.innerWidth
… = snake._el_container.clientWidth

Somewhat the calculations were off making the game not detect the Div element's border to detect correctly, and also the "food" targets where always placed in the top left...

[alessioscand]

Thank you so much for your kind feedback. I know HTML & CSS but not Javascript, so I need a simpler solution. ;)
May I ask if there is a way to set a top and bottom margin to constrain the snake and food area in the page?
Or to assign a z-index to have always the elements (snake and food) on top? Thank you so much!