CSS code not working on pages

Summary

CSS code not working on pages.

Steps to Reproduce

Add the following lines in the CSS Stylesheet macro on a page.

.page-metadata {display:none;}
#comments-section { display:none; }
#likes-and-labels-container { display:none; }
#main-header { display:none; }
#create-page-button { display:none; }
#footer { display:none; }
#quick-create-page-button { display:none; }

Expected Results

The icons for editing, managing watchers, etc. should not be displayed on the top right of the page.

Actual Results

The CSS code has no effect on the page.