.container {
  position: relative;
  max-width: 100%; /* Maximum width */
  margin: 0 auto; /* Center it */
}

.container .content {
  position: absolute; /* Position the background text */
  top: 5px; /* At the bottom. Use top:0 to append it to the top */
  left:20px;
  background: rgb(0, 0, 0); /* Fallback color */
  background: rgba(0, 0, 0, 0.2); /* Black background with 0.5 opacity */
  color: #f1f1f1; /* Grey text */
  width: 55%; /* Full width */
  padding: 5px; /* Some padding */
 overflow: auto;
  bottom: 5px;
}