Help me in solving HTML45 problem

My issue

My recent trip to Greece

<main>
    <h2 style='color: blue; front-size: 16px;'>
    <h2>Overview</h2>
    <h3>
    <ol style ='color: red; front-size: 25px;'>

        <ol> 
            <li>Greece</li>
            <li>Trip Options</li>
            <li>Trip Itinerary</li>
        </ol>
    </h3>
</main>
what mistake in this

My code

// your code goes here

Learning course: Learn HTML / CSS
Problem Link: CSS Inline styling Practice Problem in HTML / CSS - CodeChef