/* -------------------------------------------------- 广告 -------------------------------------------------- */

.ad {
	position: relative;
	overflow: hidden;
	width: 100%;
	height: 0;
	padding-bottom: 56.25%;
}

.ad > a {
	width: 100%;
	height: auto;
	position: absolute; 
	top: 50%; 
	left: 50%; 
	transform: translate(-50%, -50%);
}

.ad img {
	width: 100%; 
	height: auto;
}

.ad.banner {
	width: calc(100% - 4px);
	height: 90px;
	margin: 2px;
	padding-bottom: 0;
}

.ad.banner > a {
	width: 100%;
	height: 100%;
}

.ad.banner img {
	width: 100%;
	height: 100%;
}

.ad.fullscreen {
	position: fixed;
	z-index: 99;
	width: 100%;
	height: 100vh;
	padding-bottom: 0;
	background-color: rgba(0, 0, 0, 0.7);
	display: none;
}

.ad.fullscreen > a {
	width: 90%;
	height: auto;
}

.ad.fullscreen .countdown {
	position: absolute;
	top: 10px;
	right: 10px;
	width: 22px;
	height: 22px;
	line-height: 22px;
	border: 1px solid #fff;
	border-radius: 50%;
	z-index: 99;
	text-align: center;
	color: #fff;
}

@media screen and (max-width: 767px) {
	.ad.banner {
		height: 30px;
	}
}