I have one question. Here is example:
nav {
  width: 100%;
  background: #000;
  opacity: 0.8;
}
ul {
  background: green;
  opacity: 1;
}<nav>
  <ul>
    <li>Link1</li>
    <li>Link2</li>
  </ul>
</nav>
<header>
  <h1>123</h1>
</header>And problem is that, ul is also have opacity. By all this I mean that nav tag is okay, it has opacity of 0.8, but my ul tag shoud not have opacity, and it doesn't if you look in css in browser, but I still can see h1 text behind the ul and li tag.
 
     
    