<div class="container">
    <figure class="accordion-panel">
        <img class="accordion-image" src="https://cdn.pixabay.com/photo/2012/06/19/10/32/owl-50267_1280.jpg">
        <input class="accordion-tab" type="radio" name="radio-set" checked="checked"/>
        <figcaption class="accordion-caption"><span>stroll</span></figcaption>
        <figure class="accordion-panel">
            <img class="accordion-image" src="https://cdn.pixabay.com/photo/2020/03/01/15/30/fox-4893199_1280.jpg" alt="image02" />
            <input class="accordion-tab" type="radio" name="radio-set" />
            <figcaption class="accordion-caption"><span>families</span></figcaption>
            <figure class="accordion-panel">
                <img class="accordion-image" src="https://cdn.pixabay.com/photo/2017/01/14/12/59/iceland-1979445_1280.jpg" alt="image03" />
                <input class="accordion-tab" type="radio" name="radio-set" />
                <figcaption class="accordion-caption"><span>fawn on</span></figcaption>
                <figure class="accordion-panel">
                    <img class="accordion-image" src="https://cdn.pixabay.com/photo/2018/08/12/16/59/ara-3601194_1280.jpg" alt="image04" />
                    <input class="accordion-tab" type="radio" name="radio-set" />
                    <figcaption class="accordion-caption"><span>solitary</span></figcaption>
                    <figure class="accordion-panel">
                        <img class="accordion-image" src="https://cdn.pixabay.com/photo/2016/11/14/04/45/elephant-1822636_1280.jpg" alt="image05" />
                        <input class="accordion-tab accordion-tab-last" type="radio" name="radio-set" />
                        <figcaption class="accordion-caption"><span>conversation</span></figcaption>
                    </figure>    
                </figure>
            </figure>
        </figure>
    </figure>
</div>

.accordion-panel-container {  /* アコーディオン全体 */
    width: 638px;  /* 全体の幅.テーマに合わせる */
    box-shadow: 1px 1px 4px rgba(0, 0, 0, 0.08);
    border: 7px solid rgba(255, 255, 255, 0.6);
}
.accordion-panel {  /* パネル */
    position: absolute;
    left: 40px;  /* タブとして見せる幅 */
    width: 478px;  /* 画像の幅 */
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.6);
}
.accordion-panel-container > .accordion-panel {  /* 先頭のパネル */
    position: relative;
    left: 0;
}

.accordion-tab {  /* タブ */
    width: 40px;  /* 反応する幅 */
    height: 100%;
    cursor: pointer;
    z-index: 100;
}

/* パネルをアコーディオン状に開く */
/*
body{
    font-family: 'Open Sans Condensed','Arial Narrow', serif;
    background-color: aliceblue;
}
*/
.accordion-panel-container {
    position: relative;
    width: 638px;
    margin: 20px auto;
    overflow: hidden;
    box-shadow: 1px 1px 4px rgba(0, 0, 0, 0.08);
    border: 7px solid rgba(255, 255, 255, 0.6);
}
.accordion-panel {
    margin: 0;
    position: absolute;
    top: 0;
    left: 40px;
    width: 478px;
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.6);
    transition: 0.3s ease-in-out;
}
.accordion-panel-container > .accordion-panel {
    position: relative;
    left: 0;
}
.accordion-image {
    display: block;
}
.accordion-tab {
    position: absolute;
    top: 0;
    width: 40px;
    height: 100%;
    cursor: pointer;
    opacity: 0;
    z-index: 100;
}
.accordion-tab:checked {
    right: 0;
    width: 0;
}
.accordion-tab:checked ~ .accordion-panel {
    left: 478px;
    transition: 0.7s ease-in-out;
}

.accordion-caption span {
    position: absolute;
    top: 40%;
    margin-top: -20px;
    left: 20px;
    right: 20px;
    text-align: center;
    background: rgba(47, 79, 79, 0.25);
    line-height: 10px;
    font-size: 18px;
    opacity: 0;
    text-transform: uppercase;
    letter-spacing: 4px;
    font-weight: 700;
    padding: 20px;
    color: #fff;
    text-shadow: 1px 1px 1px rgba(0, 0, 0, 0.1);
}

/* 開いた画像と選んだタブを明るく表示 */
.accordion-caption {
    width: 100%;
    height: 100%;
    background: rgba(47, 79, 79, 0.25);
    position: absolute;
    top: 0;
    transition: 0.2s linear;
}
.accordion-tab:checked + .accordion-caption {
    background: rgba(47, 79, 79, 0);
}

.accordion-tab:hover + .accordion-caption {
    background: rgba(47, 79, 79, 0.1);
}