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JavaScript preprocessors can help make authoring JavaScript easier and more convenient. For instance, CoffeeScript can help prevent easy-to-make mistakes and offer a cleaner syntax and Babel can bring ECMAScript 6 features to browsers that only support ECMAScript 5.

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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

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HTML

            
              <body>
    <div>
        <h2>선택자</h2>
        <p>선택자에 대하여 알아보도록 하겠습니다.</p>
        <p>선택자에 대하여 알아보도록 하겠습니다.</p>
        <p>선택자에 대하여 알아보도록 하겠습니다.</p>
        <h3>선택자의 종류</h3>
        <ul>선택자
            <li>인접선택자</li>
            <li>전체선택자</li>
            <li>태그선택자(직접선택자)</li>
            <li>하위선택자</li>
            <li id="id1">아이디선택자</li>
            <li class="class1">클래스선택자1</li>
            <li class="class1">클래스선택자2</li>
            <li>자식선택자
                <ol>
                    <li>두번째메뉴1</li>
                    <li>두번째메뉴2</li>
                    <li>두번째메뉴3</li>
                </ol>
            </li>
            <li>형제선택자</li>
            <span>자식선택자로 지정되지 않았음</span>
        </ul>
        <h3>마무으리!</h3>
        <p>선택자에 대하여 알아봤습니다.</p>
        <h2>형제선택자로 선택됨</h2>
        <p>선택자에 대하여 알아봤습니다.</p>
        <p>선택자에 대하여 알아봤습니다.</p>
        <p>선택자에 대하여 알아봤습니다.</p>
        <h6>나 빼고 같은 h6를 선택할수도 있음</h6>
        <h6>나 빼고 같은 h6를 선택할수도 있음</h6>
        <h6>나 빼고 같은 h6를 선택할수도 있음</h6>
        <h6>나 빼고 같은 h6를 선택할수도 있음</h6>
    </div>
</body>
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CSS

            
              /* 전체선택자 */
* {
    margin: 5px;
    padding: 10px;
}

/* 태그(직접)선택자 */
div {
    border: 1px solid black;
}

/* 하위선택자 */
div h3 {
    color: red;
}

/* 아이디선택자 */
#id1 {
    font-size: 25px;
}

/* 클래스선택자 */
.class1 {
    font-style: italic;
}

/* 자식선택자 */
ul > li {
    color: blue;
}

/* 형제선택자 */
ul ~ h2 {
    color: green;
}

/* 인접선택자 */
h2 + p {
    color: purple;
    font-weight: bold;
    font-size: 20px;
}

h6 + h6 {
  color: #232B99;
}
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JS
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