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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <nav>
    <div class="mobile-menu-icon">&#9776;</div> <!-- モバイル用メニューアイコン -->
    <ul class="menu">
        <li><a href="#">ホーム</a></li>
        <li class="dropdown">
            <a href="#" class="dropbtn">コンテンツA</a>
            <ul class="dropdown-content">
                <li><a href="#">コンテンツA-1</a></li>
                <li><a href="#">コンテンツA-2</a></li>
                <li><a href="#">コンテンツA-3</a></li>
            </ul>
        </li>
        <li class="dropdown">
            <a href="#" class="dropbtn">コンテンツB</a>
            <ul class="dropdown-content">
                <li><a href="#">コンテンツB-1</a></li>
                <li><a href="#">コンテンツB-2</a></li>
                <li><a href="#">コンテンツB-3</a></li>
            </ul>
        </li>
        <li><a href="#">お問い合わせ</a></li>
    </ul>
</nav>
!

CSS 

              
                body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

nav {
    background-color: #333;
}

.mobile-menu-icon {
    display: none; /* デスクトップ表示時は非表示 */
    color: white;
    font-size: 24px;
    cursor: pointer;
    padding: 14px 16px;
}

.menu {
    list-style-type: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: row; /* デフォルトは横並び */
}

.menu > li {
    position: relative;
}

.menu > li > a, .dropbtn {
    display: block;
    color: white;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
}

.menu > li > a:hover, .dropdown:hover .dropbtn {
    background-color: #111;
}

.dropdown-content {
    display: none;
    position: absolute;
    background-color: #f9f9f9;
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
}

.dropdown-content li {
    width: 100%;
}

.dropdown-content li a {
    color: black;
    padding: 12px 16px;
    text-decoration: none;
    display: block;
    text-align: left;
}

.dropdown-content li a:hover {
    background-color: #f1f1f1;
}

.dropdown:hover .dropdown-content {
    display: block;
    top: 100%;
}

/* メディアクエリ: 画面幅が768px以下の場合のスタイル */
@media screen and (max-width: 768px) {
    .menu {
        flex-direction: column; /* 縦並びに変更 */
    }

    .menu > li {
        width: 100%;
    }

    .menu > li > a, .dropbtn {
        text-align: left;
        padding: 14px;
    }

    .dropdown-content {
        position: static;
        display: block; /* 常に表示 */
        background-color: #333;
    }

    .dropdown-content li a {
        color: white;
    }

    .dropdown-content li a:hover {
        background-color: #111;
    }

    .dropdown:hover .dropdown-content {
        display: block; /* スタイルのために維持 */
    }

    .mobile-menu-icon {
        display: block; /* モバイル表示時に表示 */
    }

    .menu {
        display: none; /* モバイル表示時はメニューを非表示 */
    }

    .menu.open {
        display: block; /* モバイルメニューが開いている時に表示 */
    }
}
!

JS 

              
                document.addEventListener('DOMContentLoaded', function() {
    // モバイル用メニューアイコンのクリックイベントを設定
    var mobileMenuIcon = document.querySelector('.mobile-menu-icon');
    var menu = document.querySelector('.menu');
    var dropdowns = document.querySelectorAll('.dropdown');

    mobileMenuIcon.addEventListener('click', function() {
        menu.classList.toggle('open'); // メニューが開いているか閉じているかを切り替える

        // メニューが開いている場合、すべてのサブメニューを閉じる
        if (menu.classList.contains('open')) {
            dropdowns.forEach(function(dropdown) {
                dropdown.querySelector('.dropdown-content').style.display = 'none';
            });
        }
    });

    // サブメニューのクリックイベントを設定
    dropdowns.forEach(function(dropdown) {
        dropdown.addEventListener('click', function() {
            // メニューが開いている場合、クリックされたサブメニューの状態を切り替える
            if (menu.classList.contains('open')) {
                var dropdownContent = dropdown.querySelector('.dropdown-content');
                dropdownContent.style.display = (dropdownContent.style.display === 'none' || dropdownContent.style.display === '') ? 'block' : 'none';
            }
        });
    });
});
!
999px

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