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HTML

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <main class="grid">
	<h1>My Awesome Website</h1>
	<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Nunc faucibus a pellentesque sit amet porttitor. Placerat vestibulum lectus mauris ultrices. Eu consequat ac felis donec et. Nisi est sit amet facilisis magna etiam tempor. Eget gravida cum sociis natoque penatibus et magnis. Tellus integer feugiat scelerisque varius. Vestibulum lorem sed risus ultricies tristique nulla aliquet enim tortor.</p>
	<img src='https://images.unsplash.com/photo-1490750967868-88aa4486c946?crop=entropy&cs=tinysrgb&fit=max&fm=jpg&ixid=MnwzMjM4NDZ8MHwxfHJhbmRvbXx8fHx8fHx8fDE2NTY3MDgyMTU&ixlib=rb-1.2.1&q=80&w=400' alt='Bright yellow flowers against a blue sky'>
	<article class="full-width">
		<h2>Full width section</h2>
	</article>
	<p>Nisi est sit amet facilisis. Vitae tortor condimentum lacinia quis. Imperdiet nulla malesuada pellentesque elit. Scelerisque mauris pellentesque pulvinar pellentesque habitant morbi. Ut tristique et egestas quis ipsum suspendisse ultrices gravida dictum. Eu feugiat pretium nibh ipsum consequat nisl vel pretium lectus.</p>
	<h2>Some heading</h2>
	<p>Vel risus commodo viverra maecenas accumsan lacus vel facilisis. Condimentum lacinia quis vel eros donec ac odio tempor orci. Adipiscing elit ut aliquam purus sit amet luctus. Bibendum arcu vitae elementum curabitur vitae nunc sed velit. Tincidunt praesent semper feugiat nibh sed pulvinar proin.</p>
</main>
!

CSS 

              
                * {
	box-sizing: border-box;
}

body {
	--pad: clamp(1rem, 3vw, 3rem);
	font-family: "Open Sans", sans-serif;
	line-height: 1.6;
	margin: 0;
}

h1, h2, p {
	margin-block: 0;
}

p {
	max-width: 90ch;
}

img {
	width: 100%;
	display: block;
}

.grid {
	display: grid;
	grid-template-columns: [full-start] 1fr [wrapper-start] minmax(0, 70rem) [wrapper-end] 1fr [full-end];
	gap: 0 var(--pad, 1rem);
}

.grid > * {
	grid-column: wrapper;
	margin-block-start: var(--pad);
}

.grid > :is(h1, h2) + p {
	margin-block-start: calc(var(--pad) * 0.5);
}

.full-width {
	grid-column: full;
	background: pink;
	padding: var(--pad);
	aspect-ratio: 5 / 1;
	display: grid;
	place-items: center;
}
!

JS
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999px

Console