Root cause: .code-block was missing white-space:pre-wrap, causing all
newlines and indentation to collapse into a single line in the browser.
Also collapse open/close tags to avoid leading/trailing blank lines.
- Add .c-punc CSS class for punctuation coloring in code blocks
- Wrap all angle brackets, operators and delimiters in c-punc spans
- Add title/aria-label to logo-mark for accessibility and clarity
- Fix CDN path in code sample to match actual usage (../dist/...)
- Fix indentation consistency