CSS Chaining

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

.btn,
[class*="btn-"],
[class*=" btn-"] {
  display: inline-block;
  font-weight: 500;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;

  &:hover,
  &:focus {
    color: #eee;
    text-decoration: none;
  }

  &[disabled],
  fieldset[disabled] & {
    cursor: disabled;
    opacity: .65;
  }
}

// Button brands
.btn-sneap {
  background-color: #189;
  color: #fff;
}

.btn-fire {
  background-color: #a00;
  color: #333;
}

// Button variant
.btn-rounded {
  border-radius: 4px;
}

SassMeister-output.css

.btn,
[class*="btn-"],
[class*=" btn-"] {
  display: inline-block;
  font-weight: 500;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;
}

.btn:hover,
.btn:focus,
[class*="btn-"]:hover,
[class*="btn-"]:focus,
[class*=" btn-"]:hover,
[class*=" btn-"]:focus {
  color: #eee;
  text-decoration: none;
}

.btn[disabled],
fieldset[disabled] .btn,
[class*="btn-"][disabled],
fieldset[disabled] [class*="btn-"],
[class*=" btn-"][disabled],
fieldset[disabled] [class*=" btn-"] {
  cursor: disabled;
  opacity: .65;
}

.btn-sneap {
  background-color: #189;
  color: #fff;
}

.btn-fire {
  background-color: #a00;
  color: #333;
}

.btn-rounded {
  border-radius: 4px;
}