CSS and, or

// and
<div class="class1 class2"></div>

div.class1.class2
{
  /* foo */
}
// and ex2
<input type="radio" class="class1" />

input[type="radio"].class1
{
  /* foo */
}

// or
<div class="class1"></div>
<div class="class2"></div>

div.class1,
div.class2
{
  /* foo */
}

참고 문헌

• https://stackoverflow.com/questions/2797091/css-and-and-or