How to create tabs in a form for better navigation

This is very easy to do with

1) 2 variables at the app level for style
2) a Formula-Text field with HTML enabled used at the top of the form.

"<span style="& [SpanEmpty] &">" & 
"<a>OPP: </a>"
&"</span>"
&"<span style="& [BtnDivStyle] &">" & 
"<a href='" & 
URLRoot() & "db/" & [_DBID_OPPORTUNITIES]  
& "?a=dr" 
& "&rid=" & [Opp ID]
& "&dfid=" & "11"
& "&z=" & Rurl() //Take user back
& "'style="& [BtnTextStyle] & ">Main</a>"
&"</span>"
&"<span style="& [BtnDivStyle] &">" & 
"<a href='" & 
URLRoot() & "db/" & [_DBID_OPPORTUNITIES]  
& "?a=dr" 
& "&rid=" & [Opp ID]
& "&dfid=" & "22"
& "&z=" & Rurl() //Take user back
& "'style="& [BtnTextStyle] & ">Scope</a>"
&"</span>"
&"<span style="& [BtnDivStyle] &">" & 
"<a href='" & 
URLRoot() & "db/" & [_DBID_OPPORTUNITIES]  
& "?a=dr" 
& "&rid=" & [Opp ID]
& "&dfid=" & "13"
& "&z=" & Rurl() //Take user back
& "'style="& [BtnTextStyle] & ">Estimate</a>"
&"</span>"
&"<span style="& [BtnDivStyle] &">" & 
"<a href='" & 
URLRoot() & "db/" & [_DBID_OPPORTUNITIES]  
& "?a=dr" 
& "&rid=" & [Opp ID]
& "&dfid=" & "24"
& "&z=" & Rurl() //Take user back
& "'style="& [BtnTextStyle] & ">Proposal</a>"
&"</span>"
&"<span style="& [BtnDivStyle] &">" & 
"<a href='" & 
URLRoot() & "db/" & [_DBID_OPPORTUNITIES]  
& "?a=er" 
& "&rid=" & [Opp ID]
& "&dfid=" & "12"
& "&z=" & Rurl() //Take user back
& "'style="& [BtnTextStyle] & ">Edit Proposal</a>"
&"</span>