HTML HTML5

ページ全体を半透明で覆う HTML

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<style>
.filterBlack
{
    position: fixed;
    width: 100%;
    height: 100%;
    left: 0px;
    top: 0px;
    opacity: 0.7;
    background-color: black;
}
</style>
</head>
<body>
<div class="filterBlack"></div>
<div>（適当なコンテンツ内容）</div>
</body>
</html>