user/test/com/google/gwt/resources/converter/constants.gss

@def MY_CONSTANT 15px;
@def MY_EVAL eval('com.foo.bar.foo()');
@def MY_URL resourceUrl("imageName");

@if (is("propertyname", "value1")) {
  @def MY_CONSTANT1 15px;
  @def MY_EVAL1 eval('com.foo.bar.foo()');
  @def MY_URL1 resourceUrl("imageName");
}

@if (is("propertyname", "value2")) {
  @def MY_CONSTANT1 15px;
  @def MY_EVAL1 eval('com.foo.bar.foo()');
  @def MY_URL1 resourceUrl("imageName");

  @if (is("propertyname", "value3")) {
    @def MY_CONSTANT11 15px;
    @def MY_EVAL11 eval('com.foo.bar.foo()');
    @def MY_URL11 resourceUrl("imageName");
  }
  @elseif (eval('com.google.gwt.i18n.client.LocaleInfo.getCurrentLocale().isRTL()')) {
    @def MY_CONSTANT12 15px;
    @def MY_EVAL12 eval('com.foo.bar.foo()');
    @def MY_URL12 resourceUrl("imageName");
  }
  @else  {
    @def MY_CONSTANT13 15px;
    @def MY_EVAL13 eval('com.foo.bar.foo()');
    @def MY_URL13 resourceUrl("imageName");
  }
}
@elseif (is("property", "value")) {
  @def MY_CONSTANT2 15px;
  @def MY_EVAL2 eval('com.foo.bar.foo()');
  @def MY_URL2 resourceUrl("imageName");

  @if (is("propertyname", "value4")) {
    @def MY_CONSTANT21 15px;
    @def MY_EVAL21 eval('com.foo.bar.foo()');
    @def MY_URL21 resourceUrl("imageName");
  }
  @else  {
    @def MY_CONSTANT22 15px;
    @def MY_EVAL22 eval('com.foo.bar.foo()');
    @def MY_URL22 resourceUrl("imageName");
  }
}
@else  {
  @def MY_CONSTANT3 15px;
  @def MY_EVAL3 eval('com.foo.bar.foo()');
  @def MY_URL3 resourceUrl("imageName");
}

@media print {
  .appFooter-appPanel {
    text-align: center;
  }
}

@def MY_CONSTANT4 15px;
@def MY_EVAL4 eval('com.foo.bar.foo()');
@def MY_URL4 resourceUrl("imageName");
@def MY_CONSTANT7 15px;
@def MY_EVAL7 eval('com.foo.bar.foo()');
@def MY_URL7 resourceUrl("imageName");
@def WIDTH 15px;
@def COLOR 255;
@def WHITE #fff;
@def _LEFT left;
@def _RIGHT right;
@def ACTIVE_SHADOW inset 0 1px 1px rgba(0, 0, 0, 0.2);

.foo {
  width: WIDTH;
  background: MY_URL7;
  background-image: -webkit-gradient(linear, _LEFT top, _RIGHT top, from(rgba(COLOR, COLOR, COLOR, 0)), to(WHITE));
  box-shadow: ACTIVE_SHADOW;
}