Dimensions and Units

<div class="container">
    <div class="heading-section">
        <h1 class="heading">Welcome to BigBinary Academy</h1>
        <h2 class="sub-heading">Achieving responsive font sizes using REM Value<h2>
    </div>
    <p class="description">Learn coding by actually Coding.</p>
    <button class="btn">Start Learning</button>
</div>

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Setting font sizes */

.heading {
    font-size: 32px;
}

.another-heading {
    font-size: 2rem;
}

.description {
    font-size: 1.2rem;
}

.btn {
    font-size: 1rem;
}

/* Other Styles*/

.heading {
    margin: 10px;
}

.sub-heading {
    color: #666;
    margin-bottom: 20px;
}

.description {
    color: #666;
    line-height: 1.6;
    margin-bottom: 20px;
}

.btn {
    padding: 10px 20px;
    background-color: #007bff;
    color: #fff;
    border: none;
    cursor: pointer;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

.btn:hover {
    background-color: #0056b3;
}

.container {
    max-width: 800px;
    margin: 0 20px auto;
    padding: 20px;
    background-color: #f4f4f4;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1); /* Added box shadow for depth */
}

.heading-section {
    margin-bottom: 30px;
}