Managment HTML+CSS in asp.net project

Hi guys
i'm brazilian, sorry for my bad english.
i have no knowledge about asp or asp.net, but there is a project of maintenance of content in a asp.net website. the maintenance is simple, just change some texts in the html of some pages, but when i saw the FTP server of the site, all the content files are storaged in the "bin" folder, in two formats each one:
page-name.aspx.79976eb2.compiled
App_Web_page-name.aspx.ffa44e1b.dll
 
some example of code in dll file:
-------------------------------------------------------------------
 
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$PEL
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