Mysql query with subquerys for each column with different categories

Tables:

CREATE TABLE category (
idcategory INT, 
category VARCHAR(50));

CREATE TABLE themes (
idtheme INT, 
idcategory INT, 
theme VARCHAR(50));

n numbers of categories. For this example, lets say 6. Each category has 18 themes. No more or less.

I want to do a query that shows what themes are in the database for each category, something like:

+---------------------+---------------------+---------------------+---------------------+---------------------+---------------------+
|   CATEGORY 1        |   CATEGORY 2        |   CATEGORY 3        |   CATEGORY 4        |   CATEGORY 5        |   CATEGORY 6        |
+---------------------+---------------------+---------------------+---------------------+---------------------+---------------------+
|   CAT1 - THEME 1    |   CAT2 - THEME 1    |   CAT3 - THEME 1    |   CAT4 - THEME 1    |   CAT5 - THEME 1    |   CAT6 - THEME 1    |
|   CAT1 - THEME 2    |   CAT2 - THEME 2    |   CAT3 - THEME 2    |   CAT4 - THEME 2    |   CAT5 - THEME 2    |   CAT6 - THEME 2    |
|   CAT1 - THEME 3    |   CAT2 - THEME 3    |   CAT3 - THEME 3    |   CAT4 - THEME 3    |   CAT5 - THEME 3    |   CAT6 - THEME 3    |
|   CAT1 - THEME 4    |   CAT2 - THEME 4    |   CAT3 - THEME 4    |   CAT4 - THEME 4    |   CAT5 - THEME 4    |   CAT6 - THEME 4    |
|   CAT1 - THEME 5    |   CAT2 - THEME 5    |   CAT3 - THEME 5    |   CAT4 - THEME 5    |   CAT5 - THEME 5    |   CAT6 - THEME 5    |
|   CAT1 - THEME 6    |   CAT2 - THEME 6    |   CAT3 - THEME 6    |   CAT4 - THEME 6    |   CAT5 - THEME 6    |   CAT6 - THEME 6    |
|   CAT1 - THEME 7    |   CAT2 - THEME 7    |   CAT3 - THEME 7    |   CAT4 - THEME 7    |   CAT5 - THEME 7    |   CAT6 - THEME 7    |
|   CAT1 - THEME 8    |   CAT2 - THEME 8    |   CAT3 - THEME 8    |   CAT4 - THEME 8    |   CAT5 - THEME 8    |   CAT6 - THEME 8    |
|   CAT1 - THEME 9    |   CAT2 - THEME 9    |   CAT3 - THEME 9    |   CAT4 - THEME 9    |   CAT5 - THEME 9    |   CAT6 - THEME 9    |
|   CAT1 - THEME 10   |   CAT2 - THEME 10   |   CAT3 - THEME 10   |   CAT4 - THEME 10   |   CAT5 - THEME 10   |   CAT6 - THEME 10   |
|   CAT1 - THEME 11   |   CAT2 - THEME 11   |   CAT3 - THEME 11   |   CAT4 - THEME 11   |   CAT5 - THEME 11   |   CAT6 - THEME 11   |
|   CAT1 - THEME 12   |   CAT2 - THEME 12   |   CAT3 - THEME 12   |   CAT4 - THEME 12   |   CAT5 - THEME 12   |   CAT6 - THEME 12   |
|   CAT1 - THEME 13   |   CAT2 - THEME 13   |   CAT3 - THEME 13   |   CAT4 - THEME 13   |   CAT5 - THEME 13   |   CAT6 - THEME 13   |
|   CAT1 - THEME 14   |   CAT2 - THEME 14   |   CAT3 - THEME 14   |   CAT4 - THEME 14   |   CAT5 - THEME 14   |   CAT6 - THEME 14   |
|   CAT1 - THEME 15   |   CAT2 - THEME 15   |   CAT3 - THEME 15   |   CAT4 - THEME 15   |   CAT5 - THEME 15   |   CAT6 - THEME 15   |
|   CAT1 - THEME 16   |   CAT2 - THEME 16   |   CAT3 - THEME 16   |   CAT4 - THEME 16   |   CAT5 - THEME 16   |   CAT6 - THEME 16   |
|   CAT1 - THEME 17   |   CAT2 - THEME 17   |   CAT3 - THEME 17   |   CAT4 - THEME 17   |   CAT5 - THEME 17   |   CAT6 - THEME 17   |
|   CAT1 - THEME 18   |   CAT2 - THEME 18   |   CAT3 - THEME 18   |   CAT4 - THEME 18   |   CAT5 - THEME 18   |   CAT6 - THEME 18   |
+---------------------+---------------------+---------------------+---------------------+---------------------+---------------------+

So, each column is a category and the rows are the different themes. Each category it's independant of each other and so does Themes except for those being of the same category.

I have been struggling with this for hours. Maybe I am getting old or exhausted.

any ideas of how to approach this query?