アコーディオンパネルの制作

jQuery 

<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>アコーディオンパネル</title>
<link rel="stylesheet" href="css/style.css">
</head>
<body>
<h1>アコーディオンパネルの作成</h1>


<div class="container">
<div class="accordion-box">
<h2><span class="plus"></span>お見積もりの目安を教えてください。</h2>
<p class="accordion-txt">Lorem ipsum dolor sit amet consectetur adipisicing elit. Non, consequuntur optio quam voluptate libero, aperiam possimus eos atque perspiciatis est id repellendus aspernatur magnam sint at necessitatibus. Aspernatur, distinctio dignissimos?</p>
</div><!-- /.accordion-box -->

<div class="accordion-box">
<h2><span class="plus"></span>地方ですが発注は可能でしょうか。</h2>
<p class="accordion-txt">Lorem ipsum dolor sit amet consectetur adipisicing elit. Non, consequuntur optio quam voluptate libero, aperiam possimus eos atque perspiciatis est id repellendus aspernatur magnam sint at necessitatibus. Aspernatur, distinctio dignissimos?</p>
</div><!-- /.accordion-box -->

<div class="accordion-box">
<h2><span class="plus"></span>セミナーやイベントの出演を依頼したいのですが</h2>
<p class="accordion-txt">Lorem ipsum dolor sit amet consectetur adipisicing elit. Non, consequuntur optio quam voluptate libero, aperiam possimus eos atque perspiciatis est id repellendus aspernatur magnam sint at necessitatibus. Aspernatur, distinctio dignissimos?</p>
</div><!-- /.accordion-box -->

</div><!-- /.container -->

<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js'></script>
<script src="js/script.js"></script>
</body>
</html>


style.css

@charset "utf-8";
html{box-sizing:border-box;-webkit-text-size-adjust:100%}*,:after,:before{background-repeat:no-repeat;box-sizing:inherit}:after,:before{text-decoration:inherit;vertical-align:inherit}*{padding:0;margin:0;box-sizing:border-box;}audio:not([controls]){display:none;height:0}hr{overflow:visible}article,aside,details,figcaption,figure,footer,header,main,menu,nav,section,summary{display:block}summary{display:list-item}small{font-size:80%}[hidden],template{display:none}abbr[title]{border-bottom:1px dotted;text-decoration:none}a{background-color:transparent;-webkit-text-decoration-skip:objects}a:active,a:hover{outline-width:0}code,kbd,pre,samp{font-family:monospace,monospace}b,strong{font-weight:bolder}dfn{font-style:italic}mark{background-color:#ff0;color:#000}sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}sub{bottom:-.25em}sup{top:-.5em}input{border-radius:0}[role=button],[type=button],[type=reset],[type=submit],button{cursor:pointer}[disabled]{cursor:default}[type=number]{width:auto}[type=search]{-webkit-appearance:textfield}[type=search]::-webkit-search-cancel-button,[type=search]::-webkit-search-decoration{-webkit-appearance:none}textarea{overflow:auto;resize:vertical}button,input,optgroup,select,textarea{font:inherit}optgroup{font-weight:700}button{overflow:visible}[type=button]::-moz-focus-inner,[type=reset]::-moz-focus-inner,[type=submit]::-moz-focus-inner,button::-moz-focus-inner{border-style:0;padding:0}[type=button]::-moz-focus-inner,[type=reset]::-moz-focus-inner,[type=submit]::-moz-focus-inner,button:-moz-focusring{outline:1px dotted ButtonText}[type=reset],[type=submit],button,html [type=button]{-webkit-appearance:button}button,select{text-transform:none}button,input,select,textarea{background-color:transparent;border-style:none;color:inherit}select{-moz-appearance:none;-webkit-appearance:none}select::-ms-expand{display:none}select::-ms-value{color:currentColor}legend{border:0;color:inherit;display:table;max-width:100%;white-space:normal}::-webkit-file-upload-button{-webkit-appearance:button;font:inherit}[type=search]{-webkit-appearance:textfield;outline-offset:-2px}img{border-style:none;vertical-align: bottom}progress{vertical-align:baseline}svg:not(:root){overflow:hidden}audio,canvas,progress,video{display:inline-block}@media screen{[hidden~=screen]{display:inherit}[hidden~=screen]:not(:active):not(:focus):not(:target){position:absolute!important;clip:rect(0 0 0 0)!important}}[aria-busy=true]{cursor:progress}[aria-controls]{cursor:pointer}[aria-disabled]{cursor:default}::-moz-selection{background-color:#b3d4fc;color:#000;text-shadow:none}::selection{background-color:#b3d4fc;color:#000;text-shadow:none}ul,ol{list-style:none;}a{text-decoration:none;}.wrapper{overflow:hidden;}body{overflow-y:scroll;}img{max-width: 100%;}

h1{
text-align: center;
margin: 40px 0 20px;
}
.container{
max-width: 800px;
margin: 40px auto;
}
.accordion-box{
margin-bottom: 60px;
}
h2{
font-size: 26px;
padding: 20px 20px 20px 100px;
background-color: #d9d6e4;
cursor: pointer;
position: relative;
}
.accordion-txt{
padding: 20px;
background-color: #e6d7b9;
line-height: 1.8;
font-size: 18px;
display: none;
}
.plus{
display: block;
width: 20px;
height: 2px;
background-color: #000;
position: absolute;
top: 0;
bottom: 0;
left: 40px;
margin: auto;
transition: 0.2s;
}
.plus::before{
display: block;
content: "";
width: 20px;
height: 2px;
background-color: #000;
transform: rotate(90deg);
}
.plus.click{
transform: rotate(45deg);
}


script.js

$(function(){
$('h2').on('click',function(){
$(this).next('.accordion-txt').slideToggle(400).parent('.accordion-box').siblings('.accordion-box').children('.accordion-txt').slideUp(400);

$(this).children('.plus').toggleClass('click').parents('.accordion-box').siblings('.accordion-box').find('.plus').removeClass('click');
});
});