Tx pool style and copy updates

[nuke-web3]

tweaks to style, very minor copy edit.
uses "1 idea, one line" convention over the 100 char limit.

[sacha-l]

@imadarai: is the build error coming from the "###" heading ? See error snip:

ERROR #95313

Building static HTML failed for path "/v3/concepts/tx-pool/"

See our docs page for more info on this error: https://gatsby.dev/debug-html



  61 |                     <div
  62 |                       className={`mb-2 hover:text-substrateBlue
dark:hover:text-substrateBlue-light ${
> 63 |                         activeHash === value.url.substr(1) &&
     |                                                  ^
  64 |                         'text-substrateBlue
dark:text-substrateBlue-light'
  65 |                       }`}
  66 |                     >


  WebpackError:TypeError: Cannot read property 'substr' of undefined

[nuke-web3]

I would bet so: I did this on the github editor, and there is no h2 heading preceding. This is the intended behavior BTW, I want. the title is an h1, I don't want an h2 to start in this specific case, I wan to use a h3

[imadarai]

We've come across this before and the decision was made to force a h2 before h3 always as it breaks the ToC (Table of Content) design and it looks a bit wonky

I would rather not change this convention, unless we are really in a big pickle 😶

EDIT:
#452 isn't really a bug, the check is in place on purpose to it doesn't break the design

[sacha-l]

I think I can understand where you're coming from but this would be a good opportunity to align on putting our style guide to practice. This "h3" convention doesn't match up the rest of the guides so I would lean towards consistency with the others. Thoughts on this one @lsgunnlsgunn 😃 ? Perhaps we can improve how these guidelines are articulated here..

[lsgunnlsgunn]

Having a h3 follow h1 breaks a fundamental rule. Please don't do this. If you think you have a legitimate rationale for breaking this rule, please explain what it is. (If you just don't like the size of h2 or something, let's put that in the list of visual elements we might want to revisit.) In most cases, most of your headings should be h2 level heads.