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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="wrap">
  <header id="header">
    <a href="#link1">リンク1</a>
    <a href="#link2">リンク2</a>
    <a href="#link3">リンク3</a>
    <a href="#link4">リンク4</a>
  <div id="link1">
  <div id="link2">
  <div id="link3">
  <div id="link4">
    ※ ここは下までスクロールしても届かないのでスクロール処理は中断される
  margin: 16px;
  padding-top: 16px;
  position: fixed;
  left: 0;
  background: #507cad;
  width: 100%;
  padding: 8px 24px;
    color: #fff;
    display: inline-block;
    padding: 0 4px;
  height: 100vh;
  background: linear-gradient(135deg, #b9ddf5, #6380ac);
  margin-bottom: 16px;
  padding: 40px;
  height: 64vh;
let headH = document.getElementById('header').offsetHeight;
document.body.style.marginTop = headH + "px";  //CSSの調整部分。

 * スムーススクロール実行関数
let smoothScroll = (target, offset) => {
  let toY;
  let nowY = window.pageYOffset;      //現在のスクロール値
  const divisor = 8;                  //近づく割合(数値が大きいほどゆっくり近く)
  const range = (divisor / 2) + 1;    //どこまで近づけば処理を終了するか(無限ループにならないように divisor から算出)

  const targetRect = target.getBoundingClientRect();   //ターゲットの座標取得
  const targetY = targetRect.top + nowY - offset;      //現在のスクロール値 & ヘッダーの高さを踏まえた座標
  (function () {
    let thisFunc = arguments.callee;                      //自身を呼び出すために変数に代入
    toY = nowY + Math.round((targetY - nowY) / divisor);  //次に移動する場所(近く割合は除数による。)
    window.scrollTo(0, toY);                              //スクロールさせる
    nowY = toY;                                           //nowY更新

    if (document.body.clientHeight - window.innerHeight < toY) {
      window.scrollTo(0, document.body.clientHeight);
    if (toY >= targetY + range || toY <= targetY - range) {
      window.setTimeout(thisFunc, 10);
    } else {
      //+-range の範囲内にくれば正確な値へ移動して終了。
      window.scrollTo(0, targetY);

 * アンカータグにクリックイベントを登録
const smoothOffset = headH;  //Fixされているヘッダーの高さ分スクロール先の座標をずらすために、変数に高さを入れておく
const links = document.querySelectorAll('a[href*="#"]');  //#がリンクに含まれているアンカータグを全て取得
for (let i = 0; i < links.length; i++) {
  links[i].addEventListener('click', function (e) {

    const href = e.currentTarget.getAttribute('href');   //href取得
    const splitHref = href.split('#');
    const targetID = splitHref[1];
    const target = document.getElementById(targetID);    //リンク先の要素(ターゲット)取得

    if (target) {
      smoothScroll(target, smoothOffset);
    } else {
      return true;
    return false;

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