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HTML

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About the <head>

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Insecure Resource

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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 

              
                
<h2>Here's the default browser styling for an h2</h2>

<p>And here you have a paragraph just after (and adjacent) to that level-2 heading.</p>

<p>Note how (by default) all of these elements have margins both above - and below.</p>

<h2>These styles are a nice default to have, if there's no CSS</h2>

<p>But the logic it takes to space these out is interesting. The margins overlap. That's not how margins normally work. But in this default state, this is how the spacing gets decided so that the various headings and paragraphs achieve a legible amount of spacing.</p>

<p>When two elements are adjacent (next to each other), then the one with the bigger margin takes precedent. It's not that crazy. Just think about it a little. Pretend you were in charge of designing a plan for this. It's a nice default</p>
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CSS 

              
                
h2 {
	font-size: 2rem;
}

p {
	font-size: 1rem;
	line-height: 1.3;
}

/*
    any paragraph 
    ↓
immediatly preceded by another paragraph... 
↓                                              */
p + p {
	margin-top: 1em;
}

h2 + p {
	margin-top: 1em;
}

p + h2 {
	margin-top: 1em;
}















































/* 

we've faked how this looks just to help you see what's happening behind the scenes by default











































don't think about this - and snoop around ;) 

*/


































































body {
	padding: 20px;
}

* {
	box-sizing: border-box;
}


/* We're just faking it here -- so that you can see what it's all at one time (and the dev tools only let you highlight one at a time) */
h2 {
	position: relative;
	&::before {
		display: block;
		content: '';

		position: absolute;
		top: 0;
		left: 0;

		width: 100%;
		height: 100%;

		background-color: rgb(200 0 0 / 0.2);
/* 		transform: translateY(-30%);
		padding-bottom: 1.5em; */
		border: 1px solid rgb(0 0 0 / 0.2);
	}
}

p {
	position: relative;
	padding-right: 4em;
	&::before {
		display: block;
		content: '';

		position: absolute;
		top: 0;
		left: 0;

		width: 100%;
		height: 100%;

		background-color: rgb(0 200 200 / 0.2);
/* 		transform: translateY( calc( 1em * -1 ) ); */
/* 		padding-bottom: 2em; */
		border: 1px solid rgb(0 0 0 / 0.2);
	}
}

body > * {
/* 	--depth: 15px;
	&:nth-child(2) {
		transform: translateX( calc( var(--depth) * 1 ) );
	}
	&:nth-child(3) {
		transform: translateX( calc( var(--depth) * 2 ) );
	}
	&:nth-child(4) {
		transform: translateX( calc( var(--depth) * 3 ) );
	}
	&:nth-child(5) {
		transform: translateX( calc( var(--depth) * 4 ) );
	}
	&:nth-child(6) {
		transform: translateX( calc( var(--depth) * 5 ) );
	} */
}

hr {
	padding-block: 2em;
	border: 0;
}
!

JS
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999px

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