forgeplus-react/src/forge/Source/Index.scss

.sourcePanel{
  width: 1200px;
  margin: 20px auto;
  background: #fff;
  border-radius: 2px;
  box-shadow: 0px 0px 4px rgba(0,0,0,0.1);
  .headtitle{
    padding:15px 20px;
    border-bottom: 1px solid #eee;
  }
}