Each component's layout is a bit like HTML block, which has border and padding. The `Border` property can be chosen to hide or display (with its border label), when it comes to display, in this case the space it takes is counted as padding space (i.e. `PaddingTop=PaddingBottom=PaddingLeft=PaddingRight=1`).
Note that components can be overlapped (I'd rather call this as a feature...), `Render(Renderer...)` renders its args from left to right (i.e. each component's weight is arising from left to right).
## Widgets
_APIs are subject to change, docs will be added after 2 or 3 commits_