Different elements have different default ways of how the appear following other elements.
DIV for example goes to a new line
SPAN stays inline as part of its parent
These can be overridden with the
display style.
If you wish to center a group of items you've put next to one another than you should wrap them in a DIV and center it - not the individual items.
You can check for further references here:
W3Schools Online Web Tutorials[
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