Edit in JSFiddle

<div id="i" class="a b c" name="d" style="background: yellow;">zero</div>

#i {
  display: block;
  display: inline-block;
  background: skyblue;
}

.a.b {
  background: red;
  color: blue;
}

.c {
  background: white;
  color: red;
  font-style: normal;
}

[name=d] {
  background: brown;
  color: black;
  text-decoration: underline;
  font-style: italic;
}

div {
  background: darkred;
  color: white;
  text-decoration: line-through !important;
}