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                <!DOCTYPE html>
    <title>Twelve Days of Christmas</title>
      const days = [
        '<span class="partridges">a partridge in a pear tree</span>',
        '<span class="doves">two turtle doves</span>',
        '<span class="hens">three french hens</span>',
        '<span class="birds">four calling birds</span>',
        '<span class="rings">five gold rings</span>',
        '<span class="geese">six geese a-laying</span>',
        '<span class="swans">seven swans a-swimming</span>',
        '<span class="maids">eight maids-a-milking</span>',
        '<span class="ladies">nine ladies dancing</span>',
        '<span class="lords">ten lords a-leaping</span>',
        '<span class="pipers">eleven pipers piping</span>',
        '<span class="drummers">twelve drummers drumming</span>'

      const dayLabels = [

      function singSong(){
        const contentElement =

        for(let i = 0; i < days.length; i++) {
          const dayElement = document.createElement('p');
          dayElement.innerHTML = singDay(i);

      function singDay(dayIndex) {
        let daySong = 'On the ' + dayLabels[dayIndex] + ' day of Christmas, my true love gave to me ';

        for(let i = dayIndex; i >= 0; i--) {
          daySong += days[i];

          if(i == 0){
            daySong += '!';
          } else if(i == 1){
            daySong += ', and ';
          } else {
            daySong += ', ';

        return daySong;

      body {
        background: linear-gradient(90deg, #ffaaaa 0%, #aaffaa 100%);

        font-weight: bold;

      .rings {
        background-color: gold;
        text-transform: uppercase;

  <body onload="singSong();">
    <h1>12 Days of Christmas</h1>
    <div id="content"></div>