<div class="container right-panel-active">
	<!-- Sign Up -->
	<div class="container__form container--signup">
		<form action="#" class="form" id="form1">
			<h2 class="form__title">Sign Up</h2>
			<input type="text" placeholder="User" class="input" />
			<input type="email" placeholder="Email" class="input" />
			<input type="password" placeholder="Password" class="input" />
			<button class="btn">Sign Up</button>
		</form>
	</div>

	<!-- Sign In -->
	<div class="container__form container--signin">
		<form action="#" class="form" id="form2">
			<h2 class="form__title">Sign In</h2>
			<input type="email" placeholder="Email" class="input" />
			<input type="password" placeholder="Password" class="input" />
			<a href="#" class="link">Forgot your password?</a>
			<button class="btn">Sign In</button>
		</form>
	</div>

	<!-- Overlay -->
	<div class="container__overlay">
		<div class="overlay">
			<div class="overlay__panel overlay--left">
				<button class="btn" id="signIn">Sign In</button>
			</div>
			<div class="overlay__panel overlay--right">
				<button class="btn" id="signUp">Sign Up</button>
			</div>
		</div>
	</div>
</div>
:root {
	/* COLORS */
	--white: #e9e9e9;
	--gray: #333;
	--blue: #0367a6;
	--lightblue: #008997;

	/* RADII */
	--button-radius: 0.7rem;

	/* SIZES */
	--max-width: 758px;
	--max-height: 420px;

	font-size: 16px;
	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
		Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
}

body {
	align-items: center;
	background-color: var(--white);
	background: url("https://res.cloudinary.com/dci1eujqw/image/upload/v1616769558/Codepen/waldemar-brandt-aThdSdgx0YM-unsplash_cnq4sb.jpg");
	background-attachment: fixed;
	background-position: center;
	background-repeat: no-repeat;
	background-size: cover;
	display: grid;
	height: 100vh;
	place-items: center;
}

.form__title {
	font-weight: 300;
	margin: 0;
	margin-bottom: 1.25rem;
}

.link {
	color: var(--gray);
	font-size: 0.9rem;
	margin: 1.5rem 0;
	text-decoration: none;
}

.container {
	background-color: var(--white);
	border-radius: var(--button-radius);
	box-shadow: 0 0.9rem 1.7rem rgba(0, 0, 0, 0.25),
		0 0.7rem 0.7rem rgba(0, 0, 0, 0.22);
	height: var(--max-height);
	max-width: var(--max-width);
	overflow: hidden;
	position: relative;
	width: 100%;
}

.container__form {
	height: 100%;
	position: absolute;
	top: 0;
	transition: all 0.6s ease-in-out;
}

.container--signin {
	left: 0;
	width: 50%;
	z-index: 2;
}

.container.right-panel-active .container--signin {
	transform: translateX(100%);
}

.container--signup {
	left: 0;
	opacity: 0;
	width: 50%;
	z-index: 1;
}

.container.right-panel-active .container--signup {
	animation: show 0.6s;
	opacity: 1;
	transform: translateX(100%);
	z-index: 5;
}

.container__overlay {
	height: 100%;
	left: 50%;
	overflow: hidden;
	position: absolute;
	top: 0;
	transition: transform 0.6s ease-in-out;
	width: 50%;
	z-index: 100;
}

.container.right-panel-active .container__overlay {
	transform: translateX(-100%);
}

.overlay {
	background-color: var(--lightblue);
	background: url("https://res.cloudinary.com/dci1eujqw/image/upload/v1616769558/Codepen/waldemar-brandt-aThdSdgx0YM-unsplash_cnq4sb.jpg");
	background-attachment: fixed;
	background-position: center;
	background-repeat: no-repeat;
	background-size: cover;
	height: 100%;
	left: -100%;
	position: relative;
	transform: translateX(0);
	transition: transform 0.6s ease-in-out;
	width: 200%;
}

.container.right-panel-active .overlay {
	transform: translateX(50%);
}

.overlay__panel {
	align-items: center;
	display: flex;
	flex-direction: column;
	height: 100%;
	justify-content: center;
	position: absolute;
	text-align: center;
	top: 0;
	transform: translateX(0);
	transition: transform 0.6s ease-in-out;
	width: 50%;
}

.overlay--left {
	transform: translateX(-20%);
}

.container.right-panel-active .overlay--left {
	transform: translateX(0);
}

.overlay--right {
	right: 0;
	transform: translateX(0);
}

.container.right-panel-active .overlay--right {
	transform: translateX(20%);
}

.btn {
	background-color: var(--blue);
	background-image: linear-gradient(90deg, var(--blue) 0%, var(--lightblue) 74%);
	border-radius: 20px;
	border: 1px solid var(--blue);
	color: var(--white);
	cursor: pointer;
	font-size: 0.8rem;
	font-weight: bold;
	letter-spacing: 0.1rem;
	padding: 0.9rem 4rem;
	text-transform: uppercase;
	transition: transform 80ms ease-in;
}

.form > .btn {
	margin-top: 1.5rem;
}

.btn:active {
	transform: scale(0.95);
}

.btn:focus {
	outline: none;
}

.form {
	background-color: var(--white);
	display: flex;
	align-items: center;
	justify-content: center;
	flex-direction: column;
	padding: 0 3rem;
	height: 100%;
	text-align: center;
}

.input {
	background-color: #fff;
	border: none;
	padding: 0.9rem 0.9rem;
	margin: 0.5rem 0;
	width: 100%;
}

@keyframes show {
	0%,
	49.99% {
		opacity: 0;
		z-index: 1;
	}

	50%,
	100% {
		opacity: 1;
		z-index: 5;
	}
}
const signInBtn = document.getElementById("signIn");
const signUpBtn = document.getElementById("signUp");
const fistForm = document.getElementById("form1");
const secondForm = document.getElementById("form2");
const container = document.querySelector(".container");

signInBtn.addEventListener("click", () => {
	container.classList.remove("right-panel-active");
});

signUpBtn.addEventListener("click", () => {
	container.classList.add("right-panel-active");
});

fistForm.addEventListener("submit", (e) => e.preventDefault());
secondForm.addEventListener("submit", (e) => e.preventDefault());
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