在滚动到部分时，使用相应的锚点将活动类添加到 div

const changeNav = (entries, observer) => {
    entries.forEach((entry) => {
        if(entry.isIntersecting && entry.intersectionRatio >= 0.85) {
            document.querySelector('.active').classList.remove('active');
            // get id of the intersecting section
            const id = entry.target.getAttribute('id');
            // find matching link & add appropriate class
            const newLink = document.querySelector(`[href="#${id}"]`).classList.add('active');
        }
    });
}

const options = {
    threshold: 0.85
}

const observer = new IntersectionObserver(changeNav, options);

// target the elements to be observed
const sections = document.querySelectorAll('section');
sections.forEach((section) => {
    observer.observe(section);
});

nav {
position: sticky;
top: 0px;
}

.wrapper {

    display: inline-flex;
    justify-content: space-between;
    background-color: #f4f4f4;
    padding-top: 0px;
    width: 100%;
}


element.style {
}
.nav-link.active {
    color: #aa812d;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"></script>
<div class="wrapper">
<div class="nav-container">
    <nav id="nav">
        <ul class="nav flex-column">

          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#welcome" onclick="navFunction()">
              WELCOME
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#destination" onclick="navFunction()">
              DESTINATION
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#hotel" onclick="navFunction()">
              HOTEL
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#agenda" onclick="navFunction()">
              AGENDA
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#program" onclick="navFunction()">
              PROGRAM
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#winners" onclick="navFunction()">
              WINNERS
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="http://www.somedomain.com#travel" onclick="navFunction()">
              TRAVEL
            </a>
          </li>


        </ul>
       
    </nav>
    
  </div>
  <div class="container">
  <section id="welcome" class="section">
  <h2>Welcome</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
    <br/><br/>
   Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
    <section id="destination" class="section">
  <h2>Destination</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
    <br/><br/>
   Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
      <section id="hotel" class="section">
  <h2>Hotel</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
    <br/><br/>
   Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
        <section id="agenda" class="section">
  <h2>Agenda</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
          <section id="program" class="section">
  <h2>Program</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  <br/><br/>
   Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
            <section id="winners" class="section">
  <h2>Winners</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
  <section id="travel" class="section">
  <h2>Travel</h2>
  Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  <br/><br/>
   Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.
  </section>
  </div>
  </div>