Responsive text-align classes for Bootstrap v4-alpha http://v4-alpha.getbootstrap.com/

bootstrap-v4-alpha-responsive-text-align.css

/* Responsive Text Align */

/* Text Align Up */
@media (min-width: 34em) {
  .text-center-sm-up {
    text-align: center;
  }
  .text-right-sm-up {
    text-align: right;
  }
  .text-left-sm-up {
    text-align: left;
  }
}

@media (min-width: 48em) {
  .text-center-md-up {
    text-align: center;
  }
  .text-right-md-up {
    text-align: right;
  }
  .text-left-md-up {
    text-align: left;
  }
}

@media (min-width: 62em) {
  .text-center-lg-up {
    text-align: center;
  }
  .text-right-lg-up {
    text-align: right;
  }
  .text-left-lg-up {
    text-align: left;
  }
}

@media (min-width: 75em) {
  .text-center-xl-up {
    text-align: center;
  }
  .text-right-xl-up {
    text-align: right;
  }
  .text-left-xl-up {
    text-align: left;
  }
}

/* Text Align Down */
@media (max-width: 33.9em) {
  .text-center-xs-down {
    text-align: center;
  }
  .text-right-xs-down {
    text-align: right;
  }
  .text-left-xs-down {
    text-align: left;
  }
}

@media (max-width: 37.9em) {
  .text-center-sm-down {
    text-align: center;
  }
  .text-right-sm-down {
    text-align: right;
  }
  .text-left-sm-down {
    text-align: left;
  }
}

@media (max-width: 41.9em) {
  .text-center-md-down {
    text-align: center;
  }
  .text-right-md-down {
    text-align: right;
  }
  .text-left-md-down {
    text-align: left;
  }
}

@media (max-width: 74.9em) {
  .text-center-lg-down {
    text-align: center;
  }
  .text-right-lg-down {
    text-align: right;
  }
  .text-left-lg-down {
    text-align: left;
  }
}