/*箭头样式*/
.arrow {
	position: absolute;
	bottom: 20px;
	left: 50%;
	margin-left: -25px;
	width: 50px;
	height: 50px;
	border-radius: 50%;
	animation: bounce 2.5s infinite ease-in-out;
}

.arrow:before {
	content: "";
	position: absolute;
	top: 20px;
	left: 50%;
	margin-left: -10px;
	width: 20px;
	height: 20px;
	border-top: 2px solid #FFFFFF;
	border-right: 2px solid #FFFFFF;
	transform: rotate(135deg);
}

/*箭头动画*/
@keyframes bounce {
	0%, 100% {
		bottom: 20px;
	}

	50% {
		bottom: 40px;
	}
}