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CSS

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JavaScript

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HTML 

              
                <body>
	<div class="notepad">
		<div class="list-wrapper">
			<div class="list-header">
				<h1>TO-DO LIST:</h1>
			</div>
			<div class="list-items">
				<li class="li-item" id="li-1"><input onclick="strikeGroceries()" type="checkbox" class="list-cb" id="list-cb-1"><span>Groceries</span></li>
				<li class="li-item" id="li-2"><input onclick="strikeClean()" type="checkbox" class="list-cb" id="list-cb-2"><span>Clean gutters</span></li>
				<li class="li-item" id="li-3"><input onclick="strikePoffice()" type="checkbox" class="list-cb" id="list-cb-3"><span>Post office</span></li>
				<li class="li-item" id="li-4"><input onclick="strikeAvery()" type="checkbox" class="list-cb" id="list-cb-4"><span>Call Avery</span></li>
				<li class="li-item" id="li-5"><input onclick="strikeSort()" type="checkbox" class="list-cb" id="list-cb-5"><span>Sort recycling</span> </li>
				<li class="li-item" id="li-6"><input onclick="strikeTrash()" type="checkbox" class="list-cb" id="list-cb-6"> <span>Put out trash</span></li>

			</div>
		</div>
	</div>
</body>
!

CSS 

              
                @import url("https://fonts.googleapis.com/css2?family=Codystar&family=Life+Savers:wght@400;700;800&display=swap");
@import url("https://fonts.googleapis.com/css2?family=Grape+Nuts&display=swap");

:root {
	/*Color Variables */

	$dark-purple: hsla(248, 31%, 23%, 1);
	$pink: hsla(331, 61%, 84%, 1);
	$lilac: hsla(290, 29%, 68%, 1);
	$purple: hsla(263, 44%, 57%, 1);
	$dark-grey: hsla(225, 16%, 35%, 1);
	$light-grey: hsla(224, 12%, 68%, 1);
	$light-grey-5: hsla(224, 12%, 68%, 0.5);

	$black: $dark-purple;
	$white: hsla(328, 61%, 98%, 1);

	$notepad-border: #000;
	$notepad-bg: $white;
	$list-item-border: $light-grey-5;
	$header-border: $lilac;
	$text-bg-default: $lilac;
	$text-bg-strike: $light-grey;
	$notepad-back: $dark-purple;
	$header-color: $pink;
	$header-bg: $purple;
	$list-color: $dark-purple;

	/*Text variables*/
	$header-ff: "Life Savers", sans-serif;
	$list-ff: "Grape Nuts", sans-serif;
	/* Shadows and gradients */

	$gradient-bg: linear-gradient(
		90deg,
		hsla(216, 96%, 56%, 1) 0%,
		hsla(178, 64%, 65%, 1) 100%
	);
	$gradient-list-stack: linear-gradient(
		90deg,
		$white 10%,
		$black 11%,
		$white 12%,
		$white 22%,
		$black 23%,
		$white 24%,
		$white 100%
	);

	$notepad-shadow: -2px 2px 0px 0px $black, -4px 4px 0px 0px $white,
		-6px 6px 0px 0px $black, -8px 8px 0px 0px $white, -10px 10px 0px 0px $black,
		-8px 18px 0px 8px $notepad-back;

	/*Size Variables */
	$notepad-width: 300px;
	$notepad-height: 430px;
	$li-height: $notepad-height / 11;
	$header-height: $notepad-height / 8;

	body {
		height: 100vh;
		overflow: clip;
		display: grid;
		place-items: center;
		background: $gradient-bg;
		.notepad {
			background-color: $notepad-bg;
			margin: auto;
			padding: 2rem;
			height: $notepad-height;
			width: $notepad-width;
			border: 1px solid $notepad-border;
			display: grid;
			place-content: center;
			box-shadow: $notepad-shadow;
			border-radius: 6px 6px 10px 10px;
			transform: skew(5deg);
			.list-wrapper {
				height: $notepad-height;
				width: $notepad-width;
				padding: 1rem;
				border: 1px solid $notepad-border;
				display: grid;
				grid-template-rows: auto auto;
				grid-row-gap: 20px;
				grid-template-columns: auto;
				align-content: start;
				border-radius: 10px;
				.list-header {
					border-color: $header-border;
					border-style: double;
					border-width: 8px;
					margin: auto;
					height: $header-height;
					text-align: center;
					border-radius: 8px;
					background-color: $header-bg;
					display: grid;
					align-content: center;
					padding: 0.5rem 2rem;
					h1 {
						font-size: 2rem;
						font-weight: 800;
						font-family: $header-ff;
						color: $header-color;
						border-color: $header-border;
						border-style: dotted;
						border-radius: inherit;
						border-width: 3px;
						padding: 0.25rem 0.5rem;
					}
				}
				.list-items {
					background-color: $notepad-bg;
					display: grid;
					grid-template-rows: repeat(6, $li-height);
					grid-template-columns: 100%;
					width: $notepad-width;
					grid-row-gap: 10px;
					align-content: space-between;

					.li-item {
						height: $li-height;
						margin: auto;
						width: 100%;
						list-style: none;
						display: grid;
						justify-content: space-between;
						grid-template-columns: 10% 85%;
						grid-template-rows: 100%;
						align-items: center;
						border: 1px solid $list-item-border;
						.list-cb {
							height: 25px;
							width: 30px;
							margin-left: 5px;
						}
						span {
							padding: 0.5rem;
							align-self: center;
							font-family: $list-ff;
							font-size: 1.5rem;
							color: $list-color;
						}
					}
					.striked-item {
						background-color: $text-bg-strike;
						span {
							text-decoration-line: line-through;
						}
					}
				}
			}
		}
	}
}
!

JS 

              
                function strikeGroceries() {
	var groceries = document.getElementById("li-1");
	groceries.classList.toggle("striked-item");
}

function strikeClean() {
	var clean = document.getElementById("li-2");
	clean.classList.toggle("striked-item");
}

function strikePoffice() {
	var poffice = document.getElementById("li-3");
	poffice.classList.toggle("striked-item");
}

function strikeAvery() {
	var avery = document.getElementById("li-4");
	avery.classList.toggle("striked-item");
}

function strikeSort() {
	var sortrec = document.getElementById("li-5");
	sortrec.classList.toggle("striked-item");
}

function strikeTrash() {
	var trash = document.getElementById("li-6");
	trash.classList.toggle("striked-item");
}
!
999px

Console