Треугольный div блок?

body {
  background-color: #c3deef;
  background-size: cover;
}

.triangle {
  color: #000;
  text-align: center;
  overflow: hidden;
  position: relative;
  padding-bottom: 50px;
}

.triangle > .text {
  display: block;
  padding: 10px;
  background-color: #73a0be;
}

.triangle:after {
  position: absolute;
  left: 0;
  content: "";
  width: 100%;
  height: 35px;
  background-image: linear-gradient(to top right, transparent 48%, #c3deef 2%, #73a0be 50%),
                    linear-gradient(to top left, transparent 48%, #c3deef 2%, #73a0be 50%);
  background-position: top left, top right;
  background-repeat: no-repeat;
  background-size: 50.1% 100%;
}