.sp , .sp * {
    color: #fff !important;
}

.sp a {
    color: #fff !important;
}
.sp a:hover {
}

.seo-content {
	display: none;
}

.seo-content img {
	display: none;
}<link rel="stylesheet" type="text/css" href="/usr/templates/_pr_ext.css" /><div class="demo" title="Внимание! Это демо версия!">DEMO</div>
<!--reklama-->

<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script-->
<script>
     (adsbygoogle = window.adsbygoogle || []).push({
          google_ad_client: "ca-pub-3927128035772323",
          enable_page_level_ads: true
     });
</script>

<!-- <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-3927128035772323" crossorigin="anonymous"></script> -->

<div class="sp_old">
<h2 class="hidden"><a href="/links/">Реклама спонсоров</a></h2><!--399370392950--><div id='8rtn_399370392950'></div></div>
<!--/reklama-->


.sp , .sp * {
    color: #fff !important;
}

.sp a {
    color: #fff !important;
}
.sp a:hover {
}

.seo-content {
	display: none;
}

.seo-content img {
	display: none;
}
<style>
	.portfolio li.good a {
	}
	.portfolio li.good a:before {
/*		--thumbnail: attr(data-img);*/
/*		content: var(--thumbnail);*/
		content: '';
		background-image: var(--thumbnail);
		background-repeat: no-repeat;
		background-position: center center;
		background-size: cover;
		height: 20vh;
		widht: 100%;
		display: block;
	}
/*	
	.portfolio li a[data-img]:before {
		content: attr(data-img);
		background-image: attr(data-img);
		background-repeat: no-repeat;
		background-size: cover;
		widht: 100%;
		padding: 20vh 20vh 20px 20px;
		display: block;
	}
*/
	.portfolio {
 		display: grid; 
  		grid-template-columns: 20% 20% 20% 20%;  
  		grid-column-gap: 5%;
  	}
	.portfolio li {
		list-style: none;
		margin-bottom: 2em;
/*		height: 20vh;*/
/*		width: 20%;*/
	}
	.portfolio li:not(.good) {
		display: none !important;
	}
</style>
<ul class="portfolio">

</ul>