In Selenium IDE, type "css=input[type='submit']" (locator value). Select the Find option. The "Sign in" button will be highlighted, indicating that the location value has been verified. CSS Selector is created with this attribute.
"tag:nth-of-type(n)" can be used. It will select the list's nth tag element.
The first portion of a CSS Rule is a CSS selector. It's a pattern of elements and other phrases that tells the browser which HTML elements should be chosen to apply the CSS property values from the rule to.