WooCommerce - Style cents in prices

<?php
  // WooCommerce - show cents within a class so they can be a smaller font
  // Brazilian Reals
  add_filter( 'wc_price', 'my_price', 3, 60 );
  function my_price( $return, $price, $args ) {
    // $return = price with currency symbol
    // $price = price as a number
    // $args = array (inc tax, exc tax)
    $price = str_replace( ',', '.', $price );
    $reals = intval( $price );
    $centavos = ( $price - $reals ) * 100 + 0.0001; // add a little bit for rounding errors
    // ensure $centavos has 2 characters
    $centavos_str = str_pad( $centavos, 2, '0' );
    return 'R$'.$reals.'.<span class="centavos">'.$centavos_str.'</span>';
  }

// and in custom css:
.centavos {
  font-size: 70%;
}