Anche se il mio codice è corretto mi dice che all' intestazione h2 non ho messo l'id intro

	<h2 id="Intro">Introduction</h2>
	<h3 class="standout">Classes and IDs in CSS</h3>
	<p class="standout">Classes and IDs are super easy in CSS. You're using them right now!</p>
	<h3>Regular HTML Selectors</h3>
	<p>If you don't bother with a class or ID, an HTML element just gets
	   the regular CSS styling for that element—or the default styling if you
	   don't specify any particular styling on the stylesheet.

#idIntro { color: #B83C3A }

.classstandout {
font-family: Verdana;
color: #F7AC5F }


I would make the i in intro lowercase (in both html and css)

to select a html element you would do:

h2 { /* some css code */ }

to select an id your css selector should start with a #:

#intro { /* some css code */ }

to select a class, your css selector should start with a dot (.):

.standout { /* some css code */ }

no need put the word id or class in the css selector itself

Ce l ho fatta,grazie mille stetim94,era di ieri sera che non riuscivo