Generated by SassMeister.com.

SassMeister-input-HTML.html

<input type="email" placeholder="example@gmail.com" class="input">

SassMeister-input.scss

// ----
// libsass (v3.3.2)
// ----

@mixin placeholder {
  &::-webkit-input-placeholder {@content}
  &:-moz-placeholder           {@content}
  &::-moz-placeholder          {@content}
  &:-ms-input-placeholder      {@content}  
}

.input {
  @include placeholder {
    color: red;
  }
}

@include placeholder {
  color: blue;
}

SassMeister-output.css

.input::-webkit-input-placeholder {
  color: red;
}

.input:-moz-placeholder {
  color: red;
}

.input::-moz-placeholder {
  color: red;
}

.input:-ms-input-placeholder {
  color: red;
}

::-webkit-input-placeholder {
  color: blue;
}

:-moz-placeholder {
  color: blue;
}

::-moz-placeholder {
  color: blue;
}

:-ms-input-placeholder {
  color: blue;
}

SassMeister-rendered.html

<input type="email" placeholder="example@gmail.com" class="input">