* {
		margin: 0;
		padding: 0;
	}

	html {
		scroll-behavior: smooth
	}

	body,
	ul,
	li,
	p,
	a {
		margin: 0;
		padding: 0;
	}

	li {
		list-style: none;
	}

	a {
		text-decoration: none;
	}

	body {
		width: 100%;
		overflow-x: hidden;
		margin: 0 auto;
		background: #000;
		/* 防止水平滚动 */
	}


	#nav {
		position: fixed;
		width: 100%;
		height: 70px;
		z-index: 99;
		background: linear-gradient(rgb(0, 0, 0, 1)50%, rgb(0, 0, 0, 0));
	}

	#nav_ul {
		width: 1400px;
		height: 70px;
		margin: 0 auto;
	}

	#nav_ul li {
		float: left;
		width: 150px;
		margin-right: 80px;
		text-align: center;
	}

	#nav_ul li:nth-child(1) {
		margin-right: 20px;
		width: 140px
	}

	#nav_ul li:nth-child(6) {
		margin-right: 0;
	}

	#nav a {
		color: white;
		font-size: 30px;
		font-weight: 600;
	}

	#nav a span {
		display: block;
		width: 0;
		height: 5px;
		border-radius: 5px;
		background: #fff;
		margin: 5px auto 0;
		opacity: 1;
	}

	@keyframes span_op {
		from {
			width: 0;
		}

		to {
			width: 60px;
		}
	}

	#logo {
		background: url(img/logo.webp)no-repeat;
		width: 50px;
		height: 50px;
	}

	#nav_ul li:hover span {
		animation: span_op 0.4s ease-out forwards;
	}

	#block5 ul {
		margin-top: 200px;
		width: 100%;
		text-align: center
	}

	#block5 li {
		color: #fff;
	}

	#block5 a {
		color: #fff;
	}