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HTML

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div id="app"></div>
!

CSS 

              
                * {
	margin: 0;
	padding: 0;
	overflow-x: hidden;
}

.vertical-scroll {
	position: relative;
}

.sectionA,
.sectionB,
.sectionC,
.sectionD,
.sectionE,
.sectionF,.sectionG,.sectionH{
	height: 100vh;
	display: flex;
	align-items: center;
	justify-content: center;
	font-size: 4rem;
}
.green{
	background:green;
}
.gray{
	background: gray;
}
.content-center {
	display: flex;
	align-items: center;
	justify-content: center;
}

.h-100vh {
	height: 100vh;
}

section {
	width: 100%;
}

.lightgreen {
	background: lightgreen;
}

.lightblue {
	background: lightblue;
}

.pink {
	background: pink;
}

.orange {
	background: orange;
}

.yellow {
	background: yellow;
}
.red{
	background: red;
}
.blue{
	background: blue;
}
.purple{
	background: purple;
}

.sectionC {
  height: 100vh;
  position: relative;
  display: flex;
  width: 200vw;
  display: flex;
  align-items: center;
  justify-content: center;
}
.horizontalSection {
  width: 100vw;
	height: 100vh;
}
!

JS 

              
                const { useRef, useLayoutEffect } = React;
gsap.registerPlugin(ScrollTrigger);

const App = () => {
  const mainRef = useRef();
  const aRef = useRef();
  const bRef = useRef();
  const cRef = useRef();
  const dRef = useRef();
  const eRef = useRef();
  useLayoutEffect(() => {
    const handleScroll = () => {
      // eslint-disable-next-line no-unused-vars
      const { scrollY } = window;
      // eslint-disable-next-line no-unused-vars
      const sectionOffsets = {
        aRef: aRef?.current?.offsetTop || 0,
        bRef: bRef?.current?.offsetTop || 0,
        cRef: cRef?.current?.offsetTop || 0,
        dRef: dRef?.current?.offsetTop || 0,
        eRef: eRef?.current?.offsetTop || 0
      };
    };

    const gsapContext = gsap.context(() => {
      const horizontalScrollData =      gsap.utils.toArray(".horizontalSection");
      gsap.to(horizontalScrollData, {
        xPercent: -100 * (horizontalScrollData.length - 1),
        ease: "none",
        scrollTrigger: {
          trigger: cRef.current,
          scrub: 1,
          pin: true,
          snap: {
            snapTo: 1 / (horizontalScrollData.length - 1),
            duration: { min: 0.25, max: 0.75 },
            delay: 0.125,
            ease: "power1.inOut"
          },
          end: () => `+=${cRef?.current?.offsetWidth}`
        }
      });
      // gsap for A-C vertical scroll snap
      gsap.timeline({
        scrollTrigger: {
          trigger: ".first",
          start: "top top",
          endTrigger: ".sectionC",
          // markers: true,
          end: "bottom bottom",
          snap: {
            snapTo: 1 / 2,
            duration: { min: 0.25, max: 0.75 },
            delay: 0.125,
            ease: "power1.inOut"
          }
        }
      });

      // gsap for D,E snap vertical

      gsap.timeline({
        scrollTrigger: {
          trigger: ".sectionD",
          endTrigger: "sectionE",
          start: "top bottom+=1",
          end: "bottom bottom",
          snap: {
            snapTo: 1 / 2,
            duration: { min: 0.25, max: 0.75 },
            delay: 0.125,
            ease: "power1.inOut"
          }
        }
      });
    }, mainRef);
    window.addEventListener("scroll", handleScroll);

    return () => {
      gsapContext.revert();
      window.removeEventListener("scroll", handleScroll);
    };
  });
  return (
    <div ref={mainRef}>
      <section className="sectionA orange content-center first" ref={aRef}>
        section A
      </section>
      <section className="sectionB red content-center" ref={bRef}>
        section B
      </section>
      <section className="section sectionC" ref={cRef}>
        <div className="horizontalSection green flex items-center">
          Horizontal 1
        </div>
        <div className="horizontalSection yellow flex items-center">
          Horizontal 2
        </div>
      </section>
      <div className="section green sectionD" ref={dRef}>
        section D
      </div>
      <section className="sectionE blue content-center h-100vh" ref={eRef}>
        section E
      </section>
    </div>
  );
};

ReactDOM.render(<App />, document.getElementById("app"));
!
999px

Console