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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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CSS

About CSS Preprocessors

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.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

About JavaScript Preprocessors

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

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Babel includes JSX processing.

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Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

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HTML 

              
                <p>パスワード表示機能を実装する際、 type="password" を type="text" へ切り替えると、「全角入力ができてしまう」「スクリーンリーダーで入力したパスワードが読み上げられてしまう」「ブラウザのオートコンプリートに記録されてしまう」といった数々の問題が起こりえます。そのため入力コントロールには手を加えず、 &lt;output&gt; 要素を使って表示する機能を考えてみました。</p>

<p>
	<label>Password <input type="password" id="password-input"></label>
	<button type="button" id="password-show-button" disabled="" aria-pressed="false">Show password</button>
	<output id="password-output" for="password-input" hidden=""></output>
</p>
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CSS
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JS 

              
                const passwordInputElement = document.getElementById('password-input');
const passwordOutputElement = document.getElementById('password-output');
const passwordShowButtonElement = document.getElementById('password-show-button');

passwordInputElement.addEventListener('input', (ev) => {
	const targetElementVelue = ev.target.value;

	passwordOutputElement.value = targetElementVelue;
	passwordShowButtonElement.disabled = targetElementVelue === '';
});

passwordShowButtonElement.addEventListener('click', (ev) => {
	const targetElement = ev.target;

	if (targetElement.getAttribute('aria-pressed') === 'true') {
		passwordOutputElement.hidden = true;
		targetElement.setAttribute('aria-pressed', 'false');
	} else {
		passwordOutputElement.hidden = false;
		targetElement.setAttribute('aria-pressed', 'true');
	}
});
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999px

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