相关疑难解决方法(0)

p {
  color: white;
}
\p {
  background: green;
}
\* {
  background: #bcc;
}
body \2a {
  background: red;
}
.recover {
  background: #6ea;
  color: black;
}
div {
  border: 2px solid blue;
}
ul,
li,
a {
  background: none;
}

<p>This should have a green background</p>
<div>This should have no background color</div>
<p class="recover">CSS has recovered</p>