calendar event

HTML

<div class="uthlutanir">
  <div class="event-date">
    <div class="date-tile">
      <div class="date-tile-month">
        des
      </div>
      <div class="date-tile-day">
        20
      </div>
      <div class="date-tile-weekday">
        Fös
      </div>
    </div>
    <div class="date-details">
      <strong>15:00</strong> Lorem ipsum dolor sit amet.
    </div>
  </div>
</div>

CSS

body {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 13px;
}

.uthlutanir {
  position: absolute;
  box-sizing: border-box;
}

.date-tile {
  border: 1px solid #c2c2c2;
  border-top: none;
  border-radius: 5px;
  color: #525252;
  float: left;
  font-weight: bold !important;
  background-image: -webkit-linear-gradient(#fff, #fff 1em, #e7e7e7);
  background-image: linear-gradient(#fff, #fff 1em, #e7e7e7);
  background-repeat: no-repeat;
  line-height: 1.2em;
  margin: 6.5px 0.75em;
  overflow: hidden;
  text-align: center;
  text-shadow: 0 1px 0 #fff;
  width: 4em;
  box-sizing: border-box;
}

.date-tile-month {
  background: #274472;
  border-radius: 4px 4px 0 0;
  color: #fff;
  font-size: 0.8em;
  font-weight: normal;
  letter-spacing: 0.2em;
  padding: 0 0.2em;
  text-transform: uppercase;
  text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.25);
}

.date-tile-day {
  font-size: 2em;
  padding: 0.35em 0 0.22em;
}

.date-tile-weekday {
  font-size: 0.8em;
  padding: 0 0 0.2em;
}

.date-details {
  margin-top: 6.5px;
  margin-left: 4.8em;
  color: #274472;
  background: #fff;
  border: 1px solid #ccc;
  border-radius: 0.4em;
  padding: 0.2em 0.4em;
  font-weight: normal;
  text-decoration: none !important;
  box-shadow: none;
  box-sizing: border-box;
}