The theme tutorial said:

To install your theme, you just place your theme folder inside addons in your Odoo installation.

After that, navigate to the Odoo Website module, go to Configuration ‣ Settings.

Under Website section click the Pick a Theme button, then hover over your theme and click Use this theme.

I do accordingly. My path is  /home/albert/src/odoo/addons/theme_eden, in which I put

__init__.py (with no  contect )

__manifest__.py which has the following:

{
'name': 'eDen Theme'
'description': 'Website of wonderful marriage eDen',
'version': '1.0',
'author': 'Albert Tseng'
'category': 'Theme/Creative',
'depends': ['website', 'website_theme_install'],
'data': [],
}

I reinitialize the server by the following command:

./odoo/odoo-bin --addons-path=./custom,./odoo/odoo/addons -d rd-demo -u estate --dev xml

Then I go to Configuration ‣ Settings. Under Website section click the Pick a Theme button, but I did not see any theme with the name "eDen Theme". What did I miss so that the result does not conform to the tutorial ?