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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                
<div class="shape-ex2">
    <ul class="shape-ex2-list-box">
        <li class="shape-ex2-list">
            <label class="shape-ex2-list-name" for="ex2_1-checkbox">第一層</label>
            <input type="checkbox" name="ex2_1-input" id="ex2_1-checkbox" />
            <ul class="shape-ex2-list-sec-box">
                <li class="shape-ex2-list-sec">
                    <label class="shape-ex2-list-sec-name" for="ex2_2_1-checkbox">第二層</label>
                    <input type="radio" name="ex2_2-input" id="ex2_2_1-checkbox" />
                    <ul class="shape-ex2-list-thr-box">
                        <li class="shape-ex2-list-thr-name"><span>第三層</span></li>
                        <li class="shape-ex2-list-thr-name"><span>第三層</span></li>
                    </ul>
                </li>
                <li class="shape-ex2-list-sec">
                    <label class="shape-ex2-list-sec-name" for="ex2_2_2-checkbox">第二層</label>
                    <input type="radio" name="ex2_2-input" id="ex2_2_2-checkbox" />
                    <ul class="shape-ex2-list-thr-box">
                        <li class="shape-ex2-list-thr-name"><span>第三層</span></li>
                        <li class="shape-ex2-list-thr-name"><span>第三層</span></li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>
</div>
!

CSS 

              
                .shape-ex2{
    display: block;
    transition: all .3s linear;
}
.shape-ex2 ul{
    padding-inline-start: 0px;
}
.shape-ex2 li::marker{
    font-size: 0;
}
.shape-ex2 input[type="checkbox"],
.shape-ex2 input[type="radio"]{
    position: absolute;
    opacity: 0;
    pointer-events: none;
    top: 0;
}
.shape-ex2-list-box{
    min-width: max-content;
    width: 224px;
}
.shape-ex2-list{
    position: relative;
}
.shape-ex2-list-name{
    font-size: 1.5rem;
    line-height: 2rem;
    padding-right: 1.25rem;
    padding-left: 0.625rem;
    padding-top: 0.25rem;
    padding-bottom: 0.25rem;
    background-color: rgb(209 213 219);
    display: block;
    min-width: max-content;
    position: relative;
}
.shape-ex2-list-name::after{
    content:'';
    width: 0;
    height: 0;
    border-top: 8px solid #000;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    position: absolute;
    top: calc(50% - 4px);
    right: 6px;
}
.shape-ex2-list-sec-box{
    display: none;
}
.shape-ex2-list-sec{
    position: relative;
}
.shape-ex2-list-sec-name{
    font-size: 1.125rem;
    line-height: 1.75rem;
    padding-right: 1.25rem;
    padding-left: 0.625rem;
    padding-top: 0.25rem;
    padding-bottom: 0.25rem;
    background-color: rgb(229 231 235);
    min-width: max-content;
    display: block;
    position: relative;
}
.shape-ex2-list-sec-name::after{
    content:'';
    width: 0;
    height: 0;
    border-left: 8px solid #000;
    border-top: 4px solid transparent;
    border-bottom: 4px solid transparent;
    position: absolute;
    top: calc(50% - 4px);
    right: 6px;
}
.shape-ex2-list-thr-box{
    display: none;
    position: absolute;
    top: 0px;
    left: 100%;
}
.shape-ex2-list-thr-name{
    font-size: 1rem;
    line-height: 1.5rem;
    padding-left: 0.625rem;
    padding-right: 0.625rem;
    padding-top: 0.25rem;
    padding-bottom: 0.25rem;
    background-color: rgb(243 244 246);
    min-width: max-content;
    display: block;
    position: relative;
}
.shape-ex2 input[type="checkbox"]:checked + ul,
.shape-ex2 input[type="radio"]:checked + ul{
    display: block;
}
!

JS
!
999px

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