Scaling Canvas and Layout Group

I feel slightly confused by the description of your setup, so forgive me if I am misunderstanding.

From my point of view, you wish to ac$$anonymous$$eve a result but you are using the tools that are meant to do the exact opposite.

1) Setting a minimum height in the LayoutElement of a row will prevent that row from shrinking vertically. Therefore, it will not get smaller when the window is getting smaller.

2) ContentSizeFitter is meant to force the parent to obey the wishes of the c$$anonymous$$ldren. Buttons say "We want to be that big", and parent says "ok then, I will expand until you all fit". What you want is the exact opposite: the c$$anonymous$$ldren have to obey the parent and shrink/expand to the size that the parent gives them.

Therefore, if you want the c$$anonymous$$ldren to obey the parent, you should not be using ContentSizeFitters or LayoutElements.

BUT: even if your button shrinks when the parent orders it, the font size of the text will not. Size 16 is size 16, and if the text is given less space then it will start to wrap and overflow/disappear. Likewise, the padding of the elements will remain constant: the row is 500 pixels-wide with 10 pixels of padding, or it is 100 pixels wide with 10 pixels of padding.

So what you want may be, instead, to use the Canvas Scaler component. Design your UI for a specific resolution with the scale of the canvas set to 1. During the game, detect the resolution and change the canvas scale accordingly. Then you can use all the ContentFitters and LayoutElement that you want, they will help making sure that the window looks good at the ideal resolution.