我有 3 個區塊，第二個區塊有一條線和一個滾動圓。圓圈會隨著主滾動一起滾動，當滾動停止時，圓圈會粘到最近的點，即每個塊的中心

但是我在這裡遇到這樣的問題，當主滾動穿過第二個區塊時，圓圈停止滾動並且在頁面上表現不正確

是否可以完成腳本，以便當主滾動穿過 block2 時，圓圈將自動堅持最後一個案例並完全停止滾動？當我們返回並穿過 block2 時，相應地，它應該再次工作

一般來說，問題在於最後一種情況，當滾動到達它時，圓圈不會進一步移動，也許還有另一種解決方案，而不是我建議的選項

我需要從block2開始到結束的滾動是平滑的，並且當滾動停止時，圓圈應該粘在最近的案例的中心

在我的範例中，這就是現在發生的情況，如果您停止滾動，那麼它會停留在需要的位置，但對我來說它不會正確滾動到末尾

const circle = document.querySelector(".circle");
const cases = document.querySelectorAll(".case");
let timer = null;

const detectCase = () => {
  const circleCenter = circle.offsetTop + circle.offsetHeight / 2;
  let activeCase = null,
    minDist = Infinity;
  cases.forEach((elem) => {
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    const dist = Math.abs(caseCenter - circleCenter);
    if (dist < minDist) {
      minDist = dist;
      activeCase = elem;
    }
  });
  return activeCase;
};

const handleScroll = () => {
  const {
    height: blockHeight
  } = document.querySelector(".block2").getBoundingClientRect();
  const maxTop = cases[cases.length - 1].offsetTop;
  const minTop = cases[0].offsetTop;
  let {
    height: startTop
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  circle.style.backgroundSize = `15px ${blockHeight}px`;
  circle.style.backgroundPosition = `0 ${-scrollDist}px`;
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    const active = detectCase();
    const activePos = active.offsetTop + active.offsetHeight / 2;
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    circle.style.backgroundPosition = `0 ${-activePos}px`;
    circle.style.transition = "0.5s";
    timer = null;
  }, 800);
  circle.style.transition = "";
};

const handleWindowSize = () => {
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    window.addEventListener("scroll", handleScroll);
    window.addEventListener("resize", handleScroll);
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  }
};

handleScroll();
handleWindowSize();
window.addEventListener("resize", handleWindowSize);

.block1 {
  height: 200px;
  background-color: gray;
}

.block3 {
  height: 600px;
  background-color: gray;
}

.block2 {
  height: 100%;
  position: relative;
}

.block2,
.block2 .circle {
  background: linear-gradient(214deg, rgba(79, 142, 255, 0) 0%, #4f8eff 10%, #f5e550 90%, rgba(79, 142, 255, 0) 100%) center/3px calc(100% - 100px) no-repeat;
}

.block2 .circle {
  width: 15px;
  height: 15px;
  left: calc(50% - 8px);
}

.block2 .circle,
.block2 .circle::before {
  position: absolute;
  border-radius: 50%;
}

.block2 .circle::before {
  content: "";
  inset: 3px;
  background-color: white;
}

.text {
  text-align: center;
  padding: 200px 50px;
}

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<div class="block1"></div>
<div class="block2">
  <div class="circle"></div>
  <div class="case">
    <div class="row">
      <div class="col-5 text">Text 1</div>
      <div class="col-2"></div>
      <div class="col-5 text">Text 1</div>
    </div>
  </div>
  <div class="case">
    <div class="row">
      <div class="col-5 text">Text 2</div>
      <div class="col-2"></div>
      <div class="col-5 text">Text 2</div>
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  <div class="case">
    <div class="row">
      <div class="col-5 text">Text 3</div>
      <div class="col-2"></div>
      <div class="col-5 text">Text 3</div>
    </div>
  </div>
</div>
<div class="block3"></div>