Html 视差效果-使节显示在前一节后面，而不移动内容

所以我现在有一个视差效果，效果很好，但我不知道如何使一个部分“向上滑动”并显示下一个部分，使它看起来像一个平滑的部分过渡。目前，我在第二部分的内容一直向下滚动，直到它就位为止，我似乎无法让它出现在第一部分后面。我现在有这个：

index.html：

<div class="parallax-wrapper">
    <div class="frame-top"></div>
    <section class="parallax-section part1">
        <div class="frame-bottom"></div>
        <div class="part1-sticky-container">
            <div class="part1-sticky">

            </div>
        </div>
    </section>

    <section class="parallax-section part2">
        <div class="part2-content">
            <h1 class="part2-text">
                Some text here
            </h1>
        </div>
    </section>
</div>

我想做的是这样的：

任何帮助都将不胜感激

body {
    margin: 0;
}

.parallax-wrapper {
    top: 100vh;
}

.parallax-section {
    position: relative;
}

.part1 {
    background: url("https://place-hold.it/1920x1080") no-repeat;
    width: 100vw;
    height: 100vh;
    background-size: cover;

    z-index: 4;
}

.frame-bottom {
    position: sticky;
    z-index: 100;
    top: calc(100vh - 40px);
    height: 40px;
    width: 100%;
    background-color: #111;
}

.part2 {
    margin: 0;

    background: url("https://place-hold.it/1920x1080") no-repeat;
    background-size: 100vw;
    width: 100vw;
    height: 100vh;

    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;

    z-index: 1;
}

.part2-content {
    position: sticky;
    width: 30rem;
    height: 5rem;
    z-index: 1;
    background-attachment: scroll;
    background-color: transparent;
    margin-left: calc(50% - 15rem);
    top: calc(50% - 2.5rem);
}

.part2-text {
    margin: 0;
    color: white;
    font-size: 32px;
    text-align: center;
}