SharePoint 2013 hide "Site Contents" in Quick Launch

This is actually rather easy using the title attribute selector:
#sideNavBox .ms-core-listMenu-item[title=”Site Contents”] { display: none; }

Or even target all elements with the matching href in the sideNavBox container:
#sideNavBox .ms-core-listMenu-item[href$=”/_layouts/15/viewlsts.aspx”] { display: none; }

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