set margin wrt vmin rather than vw or vh so portrait/landscape ok.
Use flex and flex-grow to put things on the same line as well as
distribute available space as needed. Given two main elements/line
so it remains simple.
In each line have one element with grows and one sits with a basic
comfortably fixed size.
Avoid browser quirk mode with DOCTYPE.
Help with accessibility a bit by specifying the language explicitly.
Specify the char encoding explicitly, inturn utf-8 is a safe bet,
even with intermixing of languages if reqd in future.
Add a cache-control http-equiv meta tag, which in all probability
will be ignored.
Defer js loading and execution, just for fun and future, not that
critical here as it stands now.
HanishKVC