Is there any way to stylize the "reply comment" page (that showed up on "comment/reply/1/1")? If yes, what will the snippets look like?

And if there any way stylizing the page using JavaScript (in page A the layout will be X, meanwhile in page B [with the same CSS] the layout will be Y)?

Also, I wonder why I don't have these lines:

* Web page addresses and e-mail addresses turn into links automatically.
* Allowed HTML tags:

<del> <blockquote> <q> <sub> <p> <br> <ul> <ol> <li> <dl> <dt> <dd> <a> <b> <u> <i> <sup>
    * Lines and paragraphs break automatically.
    * You may post code using <code>...

(generic) or

<?php
...
?>

(highlighted PHP) tags.
* Project issue numbers (ex. [#12345]) turn into links automatically.

...on my "reply to comment" form, meanwhile the others have.

Sorry if this have been asked before. I'm quiet new here.
Thank you. :D