in case of insensitivity

[tomhodgins]

.test {
  background: red;
}
.TEST {
  color: blue;
}

correct minification

.test{background:red;color:blue}

• class names (and many other things) are not case sensitive in CSS

CSSnano output

.test{background:red}.TEST{color:blue}

• .test, .TEST and any combination of lowercase and uppercase letters in class selectors are equivalent