这是一款带混合模式的jquery滚动背景视觉差特效。该特效利用css mix-blend-mode来混合背景和文字，并使用jquery来制作滚动时的视觉差效果，效果非常炫酷。

使用方法

在页面中引入jquery文件。

<script src=".js/jquery.min.js" type="text/javascript"></script>
HTML结构

视觉差效果的HTML结果如下。

<header>
  <div class="overlay">
    <div class="parallax">
      <h1>Awesome<span>Parallax Scrolling</span></h1>
      <div class="one"></div>
      <div class="two"></div>
      <div class="three"></div>
      <div class="four"></div>
      <div class="five"></div>
    </div>
  </div>
</header>
CSS样式

然后添加下面的CSS样式。

*,
*:before,
*:after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Poppins", sans-serif;
  font-size: 62.5%;
}

::-webkit-scrollbar {
  width: 0;
}

header {
  position: relative;
  height: 100vh;
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: #c6d9d3;
}
header .overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}
header .overlay h1 {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 3;
  margin: 0;
  text-transform: uppercase;
  text-align: center;
  font-size: 9rem;
  text-shadow: 25px -15px rgba(25, 42, 46, 0.04);
  color: #142124;
  mix-blend-mode: overlay;
}
header .overlay h1 span {
  margin-top: -2em;
  padding-top: 0.5em;
  display: block;
  letter-spacing: 5px;
  font-size: 1.25rem;
}
header .parallax {
  position: relative;
  width: 100%;
  height: 100%;
}
header .parallax div {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-position: 0 50%;
  background-repeat: no-repeat;
  background-size: 100%;
}
header .parallax .one {
  background-image: url("svg/mountains-1.svg");
  z-index: 4;
}
header .parallax .two {
  background-image: url("svg/mountains-2.svg");
  z-index: 3;
}
header .parallax .three {
  background-image: url("svg/mountains-3.svg");
  z-index: 2;
}
header .parallax .four {
  background-image: url("svg/mountains-4.svg");
  z-index: 1;
}
header .parallax .five {
  background-image: url("svg/mountains-5.svg");
  z-index: 0;
}
初始化插件

在页面DOM元素加载完毕之后，通过下面的方法来初始化该滚动视觉差效果。

$(window).scroll(function () {
  var a = $(this).scrollTop();
  var b = 800;
  $("h1").css({
    backgroundPosition: "center " + a / 2 + "px" });

  $(".parallax").css({
    top: a / 1.6 + "px",
    opacity: 1 - a / b });

});

// parallax scrolling

document.addEventListener("scroll", () => {
  var top = window.pageYOffset,
  var one = document.querySelector(".one"),
  var two = document.querySelector(".two"),
  var three = document.querySelector(".three"),
  var four = document.querySelector(".four"),
  var five = document.querySelector(".five");

  one.style.bottom = -(top * 0.1) + "px";
  two.style.bottom = -(top * 0.2) + "px";
  three.style.bottom = -(top * 0.3) + "px";
  four.style.bottom = -(top * 0.4) + "px";
  five.style.bottom = -(top * 0.5) + "px";
});

该带混合模式的jquery滚动背景视觉差特效的codepen网址为：https://codepen.io/andrejsharapov/pen/aPrNxP