Scrolling half by half pure #CSS by @Kseso

index.html

<article>
	<figure>
		<img src='https://unsplash.it/450/800?image=508' alt />
	</figure>
	<section>
			<div>
				<h1>Scrolling half by half</h1>
				<p>Made in pure #CSS and almost all is "old properties" method. And a bit imagination.<br/>
				Yes, the flexbox is old now.</p>
			</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=817' alt />
	</figure>
	<section>
		<div>
			<h2>I'm Kseso,<br/>
			&ldquo;a #CSS observer&rdquo;</h2>
			<p>Ramajero Argonauta, Enredique Amanuense de #CSS.</p>
		</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=948' alt />
	</figure>
	<section>
		<div>
			<h2><a href='https://escss.blogspot.com'>&xi;sCSS Blog</a></h2>
			<p>#impoCSSible inside EsCSS. A Spanish #CSS blog where the borders & limits of #CSS disappear.</p>
		</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=737' alt />
	</figure>
	<section>
		<div>
			<h2>#impoCSSible is nothing</h2>
			<p>You don´t need Javascript or #CSS processors either for almost 100% of what you want to do.</p>
		</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=870' alt />
	</figure>
	<section>
		<div>
			<h2>Idea from E.Bouças´s <a href='https://codepen.io/eduardoboucas/full/qdaOWv/'>pen</a></h2>
			<p>Without jQuery or Javascript, nor fixed position (bye IOs problems)</p>
		</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=743' alt />
	</figure>
	<section>
		<div>
			<h2>Images from unsplash.it</h2>
			<p>Because it´s the best for demos. Thanks, guys!</p>
		</div>
	</section>
	
	<figure>
		<img src='https://unsplash.it/450/800?image=452' alt />
	</figure>
	<section>
		<div>
			<h2>show the PEN.<br/>
				<a href='https://escss.blogspot.com/2017/08/scroll-half-by-half-pure-css.html'>link the POST</a></h2>
			<p>Por una web con mucho estilo, para argonautas con buen gusto.</p>
		</div>
	</section>
	
</article>

scrolling-half-by-half-pure-css-by-kseso.markdown

Scrolling half by half pure #CSS by @Kseso

A Split screen gallery

A Pen by Kseso on CodePen.

License.

style.css

*,*:before,*:after {box-sizing:inherit;margin:0; padding:0; border:0 none; position: relative;}
html {
	background: #000;
	box-sizing:border-box;
	font-family: 'Vollkorn', sans-serif;
	font-size: 1rem;
	color: #000;
}

@media screen and (min-width: 700px) {
	body > article {
		display: flex;
		flex-wrap: wrap;
	}
	figure {
		background: #eee;
		width: calc( 50% + 1px);
		height: 100vh;
		margin: 0 auto 10vh 0;
		position: sticky;
		top: 0;
		overflow: hidden;
		box-shadow: 4px -4px 8px rgba(0,0,0,.4);
			}
	figure::after {
		content: '';
		position: absolute;
		top: 5vmin;
		right: 5vmin;
		bottom: 5vmin;
		left: 45%;
		border: 2px dashed #fff;
		outline: 1px solid #fff;
		outline-offset: -5vmin;
		backdrop-filter: grayscale(1);
		pointer-events: none;
			}
	figure:nth-of-type(2n)::after {
		right: 45%;
		left: 5vmin;
	}
	section {
		background: #fff;
		width: calc(50% + 1px);
		height: 100vh;
		margin: 0 0 10vh auto;
		position: sticky;
		top: 0;
		// overflow: hidden;
		padding: 5vmin;
		box-shadow: -4px -4px 8px rgba(0,0,0,.4);
			}
	figure:nth-of-type(1),
	section:nth-of-type(1) {
		margin: 0 0 10vh 0;
		width: 50%;
			}
	figure:nth-of-type(2n) {
		margin: 0 0 10vh auto;
		box-shadow: -4px -4px 8px rgba(0,0,0,.4);
			}
	section:nth-of-type(2n) {
		margin: 0 auto 10vh 0;
		box-shadow: 4px -4px 8px rgba(0,0,0,.4);
		}
	figure:last-of-type,
	section:last-of-type {
		margin-bottom: 0;
	}
	section::before {
		background: inherit;
		z-index: 1;
		content: '';
		position: absolute;
		top: 50%;
		left:0;
		width: 7vmin;
		height: 7vmin;
		transform: translate(calc(-50% + 1px), -50%) rotate(-45deg);
		clip-path: polygon(-15% -15%, 110% 0%, 0% 110%);
		box-shadow: -4px -2px 8px rgba(0,0,0,.4);
		border-radius: 1.5vmin 0 0 0;
	}
	section:nth-of-type(2n)::before {
		left:auto;
		right: 0;
		transform: translate(calc(50% - 1px), -50%) rotate(-45deg) scale(-1);
	}
	section::after {
		content: '';
		position: absolute;
		top: 5vmin;
		right: 45%;
		bottom: 5vmin;
		left: 5vmin;
		border: 2px dashed #fff;
		outline: 1px solid #fff;
		outline-offset: -5vmin;
		backdrop-filter: invert(1);
		pointer-events: none;
	}
	section:nth-of-type(2n):after {
		right: 5vmin;
		left: 45%;
	}
	figure img {
		min-width: 100%;
		min-height: 100%;
		object-fit: cover;
		object-position: center;
	}
	section > div {
		display: flex;
		flex-direction: column;
		align-items: center;
		height: 100%;
		padding: 1rem;
	}
	h1,
	h2 {
		margin: 15% 0 auto;
		font-size: calc(5vmin + 3vmax);
		text-align: center;
		font-weight: 700;
		line-height: 1;
		word-spacing: .5rem;
	}
	p {
		text-align: right;
		width: 100%;
		font-family: "Cormorant", serif;
		font-weight: 400;
		font-style: italic;
		font-size: calc(1.5vmin + 1.75vmax);
		margin-bottom: 5%;
	}
	a {
		color: transparent;
		-webkit-text-stroke: 2px #212121;
		text-decoration: none;
    font-weight: 900;
    letter-spacing: 2px;
	}
	a:hover, a:focus {	
		-webkit-text-stroke: 1px #999;
	}
}

styles

<link href="https://fonts.googleapis.com/css?family=Cormorant:400i" rel="stylesheet" />
<link href="https://fonts.googleapis.com/css?family=Vollkorn:700" rel="stylesheet" />