縦タイムライン線描画

<div class="d05-03-01-line">
          <span class="d05-03-01-fill"></span>
          <ul class="d05-03-01-list">
            <li><span class="d05-03-01-dot"></span><b>お問い合わせ</b>フォームからご相談</li>
            <li><span class="d05-03-01-dot"></span><b>ヒアリング</b>要件を整理します</li>
            <li><span class="d05-03-01-dot"></span><b>制作</b>デザイン・実装を進行</li>
            <li><span class="d05-03-01-dot"></span><b>納品</b>公開して運用開始</li>
          </ul>
        </div>

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        .d05-03-01-list{list-style:none;margin:0;padding:0;position:relative}
        .d05-03-01-list::before{content:"";position:absolute;left:9px;top:6px;bottom:6px;width:2px;background:#e2e8f0}
        .d05-03-01-fill{position:absolute;left:9px;top:6px;width:2px;height:0;background:#4f7cff;z-index:1;transition:height 1.1s ease}
        .d05-03-01.is-in .d05-03-01-fill{height:calc(100% - 12px)}
        .d05-03-01-list li{position:relative;padding:0 0 22px 34px;font-size:13px;color:#475569;line-height:1.5;opacity:.3;transition:opacity .5s ease}
        .d05-03-01-list li:last-child{padding-bottom:0}
        .d05-03-01-list li b{display:block;color:#1e293b;font-size:14px}
        .d05-03-01-dot{position:absolute;left:3px;top:2px;width:14px;height:14px;border-radius:50%;background:#fff;border:2px solid #cbd5e1;z-index:2;transition:border-color .4s ease,background .4s ease}
        .d05-03-01.is-in .d05-03-01-list li{opacity:1}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(1){transition-delay:.15s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(2){transition-delay:.45s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(3){transition-delay:.75s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(4){transition-delay:1.05s}
        .d05-03-01.is-in .d05-03-01-dot{border-color:#4f7cff;background:#4f7cff}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(1) .d05-03-01-dot{transition-delay:.15s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(2) .d05-03-01-dot{transition-delay:.45s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(3) .d05-03-01-dot{transition-delay:.75s}
        .d05-03-01.is-in .d05-03-01-list li:nth-child(4) .d05-03-01-dot{transition-delay:1.05s}