<div class="hero">

   <h1>Full-Width Section with a Convex Curve Bottom Divider</h1>
   <h3>Using border radius and a pseudo class clipped by overflow: hidden.</h3>
  <span class="curve"></span>
  
</div>
.hero {
  background: #115d98;
  margin-bottom: 4em;
  position: relative;
  color: #fff;
  padding-top: 4em;
}

.hero .curve {
    position: relative;
    display: block;
    height: 140px;
    bottom: -140px;
    margin-top: -100px;
    overflow: hidden;
  }
  .hero .curve::after {
    border-radius: 50%;
    box-shadow: inset 0 -10px 10px rgba(0,0,0,0.05);
    height: 100px;
    bottom: 0;
    transform: translate(-5%,-100%);
    -ms-transform: translate(-5%,-100%);
    -webkit-transform: translate(-5%,-100%);
    content: "";
    position: absolute;
    width: 110%;
    z-index: -1;
    background: #115d98;
  }
.hero h1, 
.hero h3 {
  text-align: center;
}

External CSS

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External JavaScript

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