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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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Adding Classes

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About the <head>

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Insecure Resource

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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

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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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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HTML 

              
                <a href="#" class="box">
	<span></span>
	<span></span>
	<span></span>
	<span></span>
	hello world
</a>
<a href="#" class="box">
	<span></span>
	<span></span>
	<span></span>
	<span></span>
	hello world
</a>
<a href="#" class="box">
	<span></span>
	<span></span>
	<span></span>
	<span></span>
	hello world
</a>
<a href="#" class="box">
	<span></span>
	<span></span>
	<span></span>
	<span></span>
	<p>hello world</p>
	<p>hello world</p>
</a>
<a href="#" class="box light">
	<p>hello world</p>
</a>
!

CSS 

              
                body {
	background: #000;
	display: flex;
	flex-direction: column;
	justify-content: center;
	align-items: center;
}
.box {
	position: relative;
	display: block;
	padding: 20px 30px;
	letter-spacing: 1px;
	text-decoration: none;
	text-transform: uppercase;
	width: 200px;
	text-align: center;
	margin: 100px 0 0;
	transition: 0.5s;
	color: #03f2ff;
	overflow: hidden;
}

.box:hover {
	background: #03f2ff;
	color: #000;
	box-shadow: 0 0 5px #03f2ff, 0 0 25px #03f2ff, 0 0 50px #03f2ff,
		0 0 200px #03f2ff;
	-webkit-box-reflect: below 1px linear-gradient(transparent, #000);
}

.box:nth-child(1):hover {
	width: 300px;
}
.box:nth-child(1) {
	filter: hue-rotate(270deg);
}
.box:nth-child(2) {
	filter: hue-rotate(110deg);
}

.box:nth-child(4) {
	background: rgba(15, 53, 76, 0.8);
	color: white;
	font-size: 12px;
}

/* 流光效果 */
.box span {
	position: absolute;
	display: block;
}
/* 从左到右 */
.box span:nth-child(1) {
	top: 0;
	left: 0;
	width: 100%;
	height: 1px;
	background: linear-gradient(90deg, transparent, #03f2ff);
	animation: animate1 1s linear infinite;
}
@keyframes animate1 {
	0% {
		left: -100%;
	}
	50%,
	100% {
		left: 100%;
	}
}

/* 从上到下 */
.box span:nth-child(2) {
	top: -100%;
	right: 0;
	width: 1px;
	height: 100%;
	background: linear-gradient(180deg, transparent, #03f2ff);
	animation: animate2 1s linear infinite;
	animation-delay: 0.25s;
}
@keyframes animate2 {
	0% {
		top: -100%;
	}
	50%,
	100% {
		top: 100%;
	}
}

/* 从右到左 */
.box span:nth-child(3) {
	right: -100%;
	bottom: 0;
	width: 100%;
	height: 1px;
	background: linear-gradient(270deg, transparent, #03f2ff);
	animation: animate3 1s linear infinite;
	animation-delay: 0.5s;
}
@keyframes animate3 {
	0% {
		right: -100%;
	}
	50%,
	100% {
		right: 100%;
	}
}

/* 从下到上 */
.box span:nth-child(4) {
	bottom: -100%;
	left: 0;
	width: 1px;
	height: 100%;
	background: linear-gradient(360deg, transparent, #03f2ff);
	animation: animate4 1s linear infinite;
	animation-delay: 0.75s;
}
@keyframes animate4 {
	0% {
		bottom: -100%;
	}
	50%,
	100% {
		bottom: 100%;
	}
}

/* 闪烁 */
.light {
	width: 100%;
	height: 100%;
	/* animation: glint 1.6s linear 0s infinite; */
	animation: glint 2s linear infinite;
	position: relative;
}
.light::after {
	content: "";
	position: absolute;
	width: 100%;
	height: 2px;
	bottom: 0;
	left: 0;
	background: linear-gradient(
		90deg,
		transparent,
		transparent,
		rgba(48, 251, 253),
		transparent,
		transparent
	);
	box-shadow: 0 -1px 10px #03f2ff;
}
/* 闪烁 start */
@keyframes glint {
	0% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.48),
				transparent
			)
			center bottom no-repeat;
	}
	10% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.44),
				transparent
			)
			center bottom no-repeat;
	}
	20% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.4),
				transparent
			)
			center bottom no-repeat;
	}
	30% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.36),
				transparent
			)
			center bottom no-repeat;
	}
	40% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.32),
				transparent
			)
			center bottom no-repeat;
	}
	50% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.28),
				transparent
			)
			center bottom no-repeat;
	}
	60% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.24),
				transparent
			)
			center bottom no-repeat;
	}
	70% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.32),
				transparent
			)
			center bottom no-repeat;
	}
	80% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.36),
				transparent
			)
			center bottom no-repeat;
	}
	90% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.4),
				transparent
			)
			center bottom no-repeat;
	}
	100% {
		background: linear-gradient(
				to right,
				transparent,
				rgba(48, 251, 253, 0.44),
				transparent
			)
			center bottom no-repeat;
	}
}
!

JS
!
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