Icon: Favicon.cc (Uploaded by Gavin)
Homepage banner: NASA (uploaded to Archive.org by SJO'Connell)
About page banner: NASA (uploaded to Archive.org by SJO'Connell)
Credits page banner: Arkivkopia
Main font: Wix Madefor Display
Oddmerit's list of HTML and CSS resources
Mozilla HTML and CSS references
W3Schools HTML and CSS references
Web design in 4 minutes (Jeremy Thomas)
CSS tips and tricks (World Wide Web Consortium)