PL/SQL :: Use Two Temporary Tables To Assign Color To Data Results?

Example Tables and Data:

I have 5 Courses, each course has 2 assignments.

with Courses as (
select 100 courseID from dual union all
select 200 from dual union all
select 300 from dual union all
select 400 from dual union all
select 500 from dual
), Assigns as (

[code]...

I need each assignment to get a color assigned to it according to it's courseID. So my theory is that I'd have a temporary table with a list of colors; each courseID would get assigned a color but my question is how do I assign each courseID a color without anything to join the temporary table on? Once each courseID has a color, I'd join in Assigns so that each assignment has a color associated with it according to it's courseID.

--Color table with 6 colors
with Colors as (
select 'red' color from dual union all
select 'blue' from dual union all
select 'yellow' from dual union all
select 'green' from dual union all
select 'purple' from dual union all
select 'teal' from dual
)