Can't submit password, since the button is below to the bottom of the page.

HI - My auditor sent me an email with a dropbox link to submit my documents.  I click the link and it takes me to a page to log in with a password.  This is an audit for a new company so I need a new user name and password.  When the page initially launches there is a box to enter my password and below it a blue "submit" button.  As soon as I click into the password box the password rules appear below the box.  These rules add 5 lines below the password box and above the "submit" button.  So, the submit button is now below the bottom of the visible page and I need to scroll down to see and therefore, click submit.   Only there is no scroll bar and no way to advance the page so that I can get to the submit button.  So, I cannot actually enter my password and get into drop box.  HELP please!!!!