These codes are for the Neopets lookup only.
All of these codes are designed for to be used in your "style". That means you need to input these codes between two style tags. See here:
<style> CODES HERE </style>

Remove Header & Footer
#header, #footer {display:none;}

Remove Just Footer
#footer {display:none;}

Remove Just Header
#header {display:none;}

Remove Top Ad
#ban {display:none;}

Change Heading Color of Content Modules
.contentModuleHeader {background:#FF66FF;} .contentModuleHeaderAlt {background:#FF66FF;}

Change Content Module Border Color
.contentModuleTable {border-color: #000000; border-width: 1px; border-style: dotted;}

Change Background Color of Content Modules
.contentModuleContent, .contentModule, .medText {border: 1px; background-color: #FF66FF;}

Remove Background Of Content Modules (Make them transparent)
#content * {background:inherit;}

Change Header Color of Pet/Neofriend Modules
.sidebarHeader {background:#FF66FF;}

Add A Background Color To Main Pet Lookup Area
#content {background: #FF66FF;}

Add A Tiled Background To Main Pet Lookup Area
#content {background: #FFFFFF url(http://images.neopets.com/backgrounds/faeriepets.gif)}

Add A Background Color To Side Pet/Neofriend Area
.sidebar {background: #FF66FF;}

Add A Tiled Background To Side Pet/Neofriend Area
.sidebar {background: #FFFFFF url(http://images.neopets.com/backgrounds/faeriepets.gif)}