.warning {
background-color: #EFEFEF;
border: 3px solid #444;
padding: 1rem;
margin: 2rem 0;
}
.warning::before {
content: "WARNING";
background: #FFEEAA;
width: 7.5rem;
border-right: 3px solid #444;
border-bottom: 3px solid #444;
display: block;
text-align: center;
position: relative;
left: -1rem;
top: -1rem;
padding: 2px 10px;
font-weight: bold;
}
Here be dragons! This is my notice box!