h1 {
  position: relative;
  padding: 0.6em;
  background: #e0edff;
}

h1:after {
position: absolute;
content: '';
top: 100%;
left: 30px;
border: 15px solid transparent;
border-top: 15px solid #e0edff;
width: 0;
height: 0;
}

.box12{
    padding: 0.5em 1em;
    margin: 2em 0;
    color: #5989cf;
    background: #c6e4ff;
    border-bottom: solid 6px #aac5de;
    border-radius: 9px;
}
.box12 p {
    margin: 0; 
    padding: 0;
}