<script>
document.documentElement.dataset.embed = window.location.search.includes('type=embed') ? "yep" : "nope";
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<main>
	<h1>Styling <code>&lt;details&gt;</code>: Half opened disclosure widget</h1>

	<p class="warning">Your browser does not support <code>::details-content</code>, so this demo won’t work as intended. Please use a browser with support – such as Chrome 131 or newer – to check out this page.</p>

	<h2>Demo</h2>
	
	<div id="demo">
			<details>
			<summary>
				<span class="is-open">Read Less</span>
				<span class="is-closed">Read More</span>
			</summary>
			<div class="details-content-wrapper">
				<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Dolor, aliquam. Veritatis consequatur, soluta molestiae voluptates accusamus qui odio, error, repellat rem harum id similique omnis quod dignissimos saepe quas mollitia.</p>
				<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Dolor, aliquam. Veritatis consequatur, soluta molestiae voluptates accusamus qui odio, error, repellat rem harum id similique omnis quod dignissimos saepe quas mollitia.</p>
				<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Dolor, aliquam. Veritatis consequatur, soluta molestiae voluptates accusamus qui odio, error, repellat rem harum id similique omnis quod dignissimos saepe quas mollitia.</p>
				<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Dolor, aliquam. Veritatis consequatur, soluta molestiae voluptates accusamus qui odio, error, repellat rem harum id similique omnis quod dignissimos saepe quas mollitia.</p>
				<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Dolor, aliquam. Veritatis consequatur, soluta molestiae voluptates accusamus qui odio, error, repellat rem harum id similique omnis quod dignissimos saepe quas mollitia.</p>
			</div>
		</details>
	</div>

	<p>Demo for <a href="https://developer.chrome.com/blog/styling-details" target="_top">https://developer.chrome.com/blog/styling-details</a>, built after <a href=" https://www.bol.com/be/nl/p/emerio-po-115984-pizzarette-6-personen/9200000094697866/" target="_top">https:/www.bol.com/</a></p>

	<h2>The Code</h2>
	
	<h3>UI</h3>
	
	<pre><code>/* Nothing special to report */</code></pre>
	
	<h3>Animation</h3>
	<pre><code>::details-content {
	content-visibility: visible; /* Make it always visible */
	
	transition: height 0.5s ease;
	height: 150px;
	overflow: clip;
}

[open]::details-content {
	height: calc-size(auto, size + 0.5rem); /* calc-size because we need to add a length */
}</code></pre>
</main>
@supports selector(::details-content) {
	.warning {
		display: none;
	}
}

#demo {
	padding-bottom: 2rem;
}

details {
	.is-open {
		display: none;
	}
	.is-closed {
		display: block;
	}
}

details[open] {
	.is-open {
		display: block;
	}
	.is-closed {
		display: none;
	}
}

details {
	background: white;
	position: relative;
	border-bottom: 1px solid #ccc;
}

summary {
	&::marker {
		content: '';
	}
	
	position: absolute;
	width: min-content;
	white-space: nowrap;
	color: blue;
	border: 1px solid blue;
	background: white;
	cursor: pointer;
	border-radius: 2px;
	transition: background 0.25s, color 0.25s;
	z-index: 2;
	
	&:hover {
		outline: 1px solid;
	}
	
	&:active {
		color: white;
		background: blue;
	}
	
	padding: 0.5rem 1rem;
	bottom: 0;
	left: 50%;
	transform: translate3d(-50%,50%,0)
}

.details-content-wrapper {
	padding: 0.5rem;
	
	&::before {
		content: '';
		height: 3rem;
		width: 100%;
		background-image: linear-gradient(to bottom, rgb(255 255 255 / 0), rgb(255 255 255 / 1));
		position: absolute;
		left: 0;
		bottom: 0;
		pointer-events: none;
		transition: opacity 0.5s ease;
	}
	
	[open] &::before {
		opacity: 0;
	}
}

::details-content {
	content-visibility: visible; /* Make it always visible */
	
	transition: height 0.5s ease;
	height: 150px;
	overflow: clip;
}

[open]::details-content {
	height: calc-size(auto, size + 0.5rem); /* calc-size because we need to add a length */
}

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

	html,
	body {
		height: 100%;
	}
	
	html {
		font-size: 14px;
	}
}

@layer baselayout {
	html {
		color: #444;
		font-family: system-ui;
		line-height: 1.42;
		
		overscroll-behavior-x: none;
		overflow: auto;
	}

	main {
		max-width: 90ch;
		margin: 0 auto;
		padding-bottom: 10rem;
	}

	p {
		margin-bottom: 1em;
	}
	
	h1, h2 {
		margin: 4em 0 1em;
	}
	h3 {
		margin: 1em 0 0.5em;
	}
	
	#demo {
		padding: 1em;
		border: 1px solid #ccc;
		background: #f4f6f9;
	}
}

@layer code {
	pre {
		border: 1px solid #dedede;
		padding: 1em;
		background: #f7f7f7;
		font-family: "Courier 10 Pitch", Courier, monospace;
		overflow-x: auto;
		border-left: 0.4em solid cornflowerblue;
		tab-size: 4;
	}

	code:not(pre code) {
		background: #f7f7f7;
		border: 1px solid rgb(0 0 0 / 0.2);
		padding: 0.1rem 0.3rem;
		margin: 0.1rem 0;
		border-radius: 0.2rem;
		/* 			display: inline-block; */
		-webkit-box-decoration-break: clone;
		white-space: pre-wrap;
	}
}

@layer warning {
	.warning {
		box-sizing: border-box;
		padding: 1em;
		margin: 1em 0;
		border: 1px solid #ccc;
		background: rgba(255 255 205 / 0.8);
	}

	.warning > :first-child {
		margin-top: 0;
	}

	.warning > :last-child {
		margin-bottom: 0;
	}

	.warning a {
		color: blue;
	}
	.warning--info {
		border: 1px solid #123456;
		background: rgb(205 230 255 / 0.8);
	}
	.warning--alarm {
		border: 1px solid red;
		background: #ff000010;
	}
}

/* Hide a bunch of stuff when embedded */
:root[data-embed="yep"] {
	main {
		padding: 2em 1em;
		
		:not(p.warning, p.warning *, #demo, #demo *, #demo ~ p, #demo ~ p *) {
			display: none;
		}
	}
	#demo ~ p {
		margin-top: 1em;
		text-align: center;
	}
}

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