body {
  background-color: black;
  margin: 0;
  padding: 0;
}

/* Make the div responsive */
#div1 {
  background-color: white;
  font-size: 1.2rem;          /* Scales on mobile */
  border: 2px solid red;
  
  width: 90%;                 /* Instead of 100px */
  max-width: 400px;           /* Optional limit */
  height: auto;

  margin: 20px auto;          /* Center on all screens */
  padding: 15px;              /* Adds breathing room */
  box-sizing: border-box;     /* Prevents overflow */
}

.divp1 {
  color: blue;
}

/* Mobile-specific tweaks */
@media (max-width: 480px) {
  #div1 {
    font-size: 1rem;          /* Reduce text slightly */
    padding: 10px;
  }
}