star_wars.css

html {
    width: 100%;
    overflow-x: hidden;
}
body {
    width: 100%;
}
p {
    margin: 0 0 20px 0;
}
p,
ul {
    font-family: 'Open Sans Condensed', sans-serif;
    font-size-adjust: 0.488;
    font-weight: 200;
    font-style: normal;
}
img {
    border: 0;
    width: 100%;
}
h1,
#pixels {
    font-family: 'Open Sans Condensed', sans-serif;
    font-size-adjust: 0.40;
    font-weight: 700;
    font-style: normal;
}
h2 {
    font-family: 'Open Sans Condensed', sans-serif;
    font-size-adjust: 0.531;
    font-weight: 800;
    font-style: normal;
    font-size: 45px;
    line-height: 52px;
}
#header h1,
#pixels {
    color: #48941A;
}
.float-left {
    float: left;
    margin: 0 0 0 0px;
}
.float-right {
    float: right;
    margin: 0 0px 0 0;
}
.center {
    font-size: 2.5em;
    padding: 80px 0 0 0;
    text-align: center;
}
#nav {
    list-style: none;
    position: fixed;
    right: 20px;
}
#nav li {
    margin: 0 0 15px 0;
}
#header,
#intro,
#second {
    width: 100%;
}
#intro {
    background: url(https://www.solodev.com/assets/Star%20Wars%20Parallax/starwars.jpg) 50% 0 no-repeat fixed;
    background-size: cover;
    color: white;
    height: 600px;
    margin: 0 auto;
    padding: 0;
    width: 100%;
}
#second {
    background: url(https://www.solodev.com/assets/Star%20Wars%20Parallax/starwars1.jpg) 50% 0 no-repeat fixed;
    background-size: cover;
    color: white;
    height: 1300px;
    margin: 0 auto;
    overflow: hidden;
    padding: 0;
    width: 100%;
}
#second .bg {
    background: url(https://www.solodev.com/assets/Star%20Wars%20Parallax/deathstar-white.png) 50% 500px no-repeat fixed;
    height: 1300px;
    margin: 0 auto;
    padding: 0;
    position: absolute;
    left: 0;
    z-index: 200;
    max-width: 1900px;
    width: 100%;
    overflow: hidden;
}
#third {
    background: url(https://www.solodev.com/assets/Star%20Wars%20Parallax/starwars2.jpg) 50% 0 no-repeat fixed;
    background-size: cover;
    color: black;
    height: 650px;
    padding: 100px 0 0 0;
    width: 100%;
    overflow: hidden;
    padding: 0;
    color: #fff;
}
#fifth {
    background: #ccc;
    height: 400px;
    margin: 0 auto;
    padding: 40px 0 0 0;
}
.story {
    margin: 0 auto;
    max-width: 1170px;
    overflow: hidden;
    width: 100%;
    height: 100%;
}
.story .float-left,
.story .float-right {
    padding: 100px 0 0 0;
    position: relative;
    width: 350px;
    min-width: 480px;
    width: 33%;
    background: rgba(0, 0, 0, 0.75);
    height: 100%;
    padding: 5% 50px;
    z-index: 300;
}

star_wars.html

<div id="intro">
   <div class="story">
      <div class="float-left">
         <h2>Star Wars: A New Parallax</h2>
         <p>Em preparação para o próximo "Star Wars: Rogue One" a equipe Gauntē decidiu escrever um post 
            temático Star Wars sobre a adição de parallax usando jQuery ScollTo.</p> 
      </div>
   </div>
   <!--.story-->
</div>
<div id="second">
   <div class="story">
      <div class="bg"></div>
      <div class="float-right">
         <h2>The Parallax Strikes Back</h2>
         <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean nibh erat, sagittis sit 
            amet congue at, aliquam eu libero. Integer molestie, turpis vel ultrices facilisis, nisi 
            mauris sollicitudin mauris, volutpat elementum enim urna eget odio.</p>
      </div>
   </div>
   <!--.story-->
</div>
<div id="third">
   <div class="story">
      <div class="float-left">
          <h2>The Return of Parallax</h2>
        <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean nibh erat, sagittis sit amet 
           congue at, aliquam eu libero. Integer molestie, turpis vel ultrices facilisis, nisi mauris 
           sollicitudin mauris, volutpat elementum enim urna eget odio.</p>
      </div>
   </div>
   <!--.story-->
</div>

start_wars.js

$(document).ready(function(){
        $('#intro').parallax({offsetY:-150,speedFactor:0.2});
        $('#second').parallax({speedFactor:0.2});
        $('.bg').parallax({offsetX:"0%",offsetY:200,speedFactor:0.4});
        $('#third').parallax({speedFactor:0.4});
});