Hide Ribbon on SharePoint 2013 using CSS

In SharePoint 2013 MS has divided whole ribbon in two section: s4-ribbonrow and suiteBar.

Step 1)  Add the style tag to hide the ribbon for all the user in master page
#s4-ribbonrow, #suiteBar { display : none; }

Step 2) Find out the
tag and insert the following code inside this div: