Ribbon
HTML
<div class="ribbon">
<!-- The left side -->
<div class="ribbon__side ribbon__side--l"></div>
<!-- The left triangle displayed below the content -->
<div class="ribbon__triangle ribbon__triangle--l"></div>
<!-- The right triangle displayed below the content -->
<div class="ribbon__triangle ribbon__triangle--r"></div>
<!-- The right side -->
<div class="ribbon__side ribbon__side--r"></div>
<!-- The content -->
<div class="ribbon__content"></div>
</div>
CSS
.ribbon {
/* Center the content */
align-items: center;
display: flex;
justify-content: center;
/* Size */
height: 2rem;
/* Use to position the corners */
position: relative;
}
.ribbon__content {
/* Background color */
background-color: #9ca3af;
z-index: 1;
height: 100%;
width: 100%;
}
.ribbon__side {
bottom: -0.5rem;
position: absolute;
/* Displayed under the ribbon */
z-index: 1;
/* Background */
border: 1rem solid #d1d5db;
}
.ribbon__side--l {
/* Position */
left: -1.5rem;
border-color: #d1d5db #d1d5db #d1d5db transparent;
}
.ribbon__side--r {
/* Position */
right: -1.5rem;
border-color: #d1d5db transparent #d1d5db #d1d5db;
}
.ribbon__triangle {
position: absolute;
top: 100%;
border: 0.5rem solid transparent;
border-bottom-width: 0;
border-top-color: #aaa;
}
.ribbon__triangle--l {
border-right-width: 0;
left: 0;
}
.ribbon__triangle--r {
border-left-width: 0;
right: 0;
}
Demo