Calendar

  <Loop type=calendar_year>
    <time datetime="{Field year}" class="year">
      <Set calendar_year><Field year /></Set>
      <Loop type=calendar_month>
        <Set calendar_month><Date format="m" from_format="n"><Field month /></Date></Set>
        <time datetime="{Get calendar_year}-{Get calendar_month}" class="month">
          <Field name /> <Get calendar_year />
          <div class="week">
            <Loop type=calendar_weekday>
              <abbr title="{Field name}"><Field short_name /></abbr>
            </Loop>
          </div>
          <Loop field=week>
            <time datetime="{Get calendar_year}-W{Field week}" class="week">
              <Loop field=day>
                <If check="{Date format='Y-m-d'}" value="{Field date}">
                  <Set dateClassToday>today</Set>
                  <Else />
                  <Set dateClassToday></Set>
                </If>
                <If check="{Get calendar_month}" value="{Field date format=m}">
                  <Set dateClassMonth></Set>
                  <Else />
                  <Set dateClassMonth>not-this-month</Set>
                </If>
                <div class="calendar-day {Get dateClassToday} {Get dateClassMonth}">
                  <time datetime="{Field date}"><Field day /></time>
                </div>
              </Loop>
            </time>
          </Loop>
        </time>
      </Loop>
    </time>
  </Loop>

Example Output:

Some simple styling to get you started:

.week {
  display: -ms-flexbox;
  display: -webkit-flex;
  display: flex;
  text-align: center;
}

.week > * {
  -ms-flex: 1 0 calc(100% / 7);
  flex: 1 0 calc(100% / 7);
}

.month-label {
  font-weight: bold;
  text-align: center;
}

.today time {
  background: blue;
  color: #fff;
}

.not-this-month time {
  color: #aaa;
}

.calendar-day {
  padding: .5rem;
  min-height: 5rem;
  position: relative;
  text-align: center;
}

.calendar-day time {
  margin: 2px 0;
  text-align: center;
  display: inline-block;
  vertical-align: middle;
  width: 2rem;
  height: 2rem;
  line-height: 2rem;
  border-radius: 2rem;
}