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CSS

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JavaScript

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HTML 

              
                <h1 class="title">101<span>JS</span></h1>
<div class="container">
	<h2 class="subtitle">Character Counter</h2>

	<div class="content">
		<p>Counts characters provided from the textarea <strong>maxlength</strong></p>
		<article>
			<textarea name="character-counter" cols="30" rows="10" maxlength="200"></textarea>
			<i>Characters remaining: <span>200</span></i>
		</article>
	</div>
</div>
!

CSS 

              
                * {
	font-family: "Montserrat", sans-serif;
}
html,
body {
	margin: 0;
}
body {
	background-color: #121212;
}
.title {
	margin: 0;
	font-family: "Press Start 2P", cursive;
	display: block;
	height: 60px;
	font-size: 3rem;
	line-height: 1.3;
	text-align: center;
	background: linear-gradient(to bottom, #252525 50%, darkorange 50%);
	background-clip: text;
	-webkit-background-clip: text;
	-webkit-text-fill-color: transparent;

	span {
		font-family: "Press Start 2P", cursive;
		font-size: 1rem;
	}

	&:after {
		content: "";
		width: 100%;
		height: 30px;
		display: block;
		background-color: darkorange;
		position: absolute;
		z-index: -1;
		top: 0;
	}
}
.subtitle {
	font-family: "Press Start 2P", cursive;
	font-size: 1rem;
	color: #dedede;
	border-bottom: 1px solid darkorange;
	line-height: 2;
	margin-bottom: 10px;
}
.container {
	margin: 20px;
}
.content {
	color: #dedede;

	pre {
		border: 1px solid grey;
		background-color: rgba(255, 255, 255, 0.05);
		padding: 10px;
	}

	textarea,
	input[type="text"] {
		border: 1px solid darkgrey;
		border-radius: 5px;
		padding: 5px;
		background-color: rgba(255, 255, 255, 0.05);
		color: #dedede;
	}
}

/*
Minimal styling needed for the i element which shows the remaining characters
*/
i {
	font-size: 0.8rem;
	display: block;
}
!

JS 

              
                /*
 * CharacterCounter
 * @param textareaEl = textarea html element
 * @param remainingEl = element that includes the remaining value, updates with each event fire (keyUp)
 */
class CharacterCounter {
	constructor(textareaEl, remainingEl) {
		this.element = textareaEl;
		this.remainingEl = remainingEl;
		this.max = this.element.getAttribute("maxlength");
		this.remainingChars = this.max;
		this.currCounter = this.element.value.length;
		this.setEvents();
	}

	/* calculates the remaining characters
	 * @param event = event triggered from event listener
	 */
	calc(event) {
		this.remainingChars = this.element.value.length;
		this.updateRemainingEl();
	}

	/* sets the events that will be attacked on the element
	 */
	setEvents() {
		this.element.addEventListener("keyup", (event) => this.calc(event));
	}

	/* updates the remainingEl markup with the current remaining char value
	 */
	updateRemainingEl() {
		this.remainingEl.textContent = this.max - this.remainingChars;
	}
}

var textarea = document.getElementsByName("character-counter")[0];
var remaining = document.querySelector("i span");
characterCounter = new CharacterCounter(textarea, remaining);
!
999px

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