<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Semantic HTML Example</title><!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Form Validation Example</title>
<style><!DOCTYPE html>
<html lang="en">
<head>
<!-- Essential meta tags -->
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">/* BEM - Block Element Modifier */
/* BLOCK - Independent component */
.card {
padding: 1rem;
border: 1px solid #ddd;