ionic-framework/vendor/ionicons/scss/_ionicons-animation.scss

// Animation Icons
// --------------------------

.#{$ionicons-prefix}spin {
  -webkit-animation: spin 1s infinite linear;
  -moz-animation: spin 1s infinite linear;
  -o-animation: spin 1s infinite linear;
  animation: spin 1s infinite linear;
}

@-moz-keyframes spin {
  0% { -moz-transform: rotate(0deg); }
  100% { -moz-transform: rotate(359deg); }
}
@-webkit-keyframes spin {
  0% { -webkit-transform: rotate(0deg); }
  100% { -webkit-transform: rotate(359deg); }
}
@-o-keyframes spin {
  0% { -o-transform: rotate(0deg); }
  100% { -o-transform: rotate(359deg); }
}
@-ms-keyframes spin {
  0% { -ms-transform: rotate(0deg); }
  100% { -ms-transform: rotate(359deg); }
}
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(359deg); }
}


.#{$ionicons-prefix}loading-a,
.#{$ionicons-prefix}loading-b,
.#{$ionicons-prefix}loading-c,
.#{$ionicons-prefix}loading-d,
.#{$ionicons-prefix}looping,
.#{$ionicons-prefix}refreshing,
.#{$ionicons-prefix}ios7-reloading {
  @extend .ion;
  @extend .#{$ionicons-prefix}spin;
}

.#{$ionicons-prefix}loading-a:before { 
  @extend .#{$ionicons-prefix}load-a:before;
}

.#{$ionicons-prefix}loading-b:before { 
  @extend .#{$ionicons-prefix}load-b:before;
}

.#{$ionicons-prefix}loading-c:before { 
  @extend .#{$ionicons-prefix}load-c:before;
}

.#{$ionicons-prefix}loading-d:before { 
  @extend .#{$ionicons-prefix}load-d:before;
}

.#{$ionicons-prefix}looping:before { 
  @extend .#{$ionicons-prefix}loop:before;
}

.#{$ionicons-prefix}refreshing:before { 
  @extend .#{$ionicons-prefix}refresh:before;
}

.#{$ionicons-prefix}ios7-reloading:before { 
  @extend .#{$ionicons-prefix}ios7-reload:before;
}