Mobile-First Design Approach in CSS

/* Mobile-First CSS */
.container {
  width: 100%;
  padding: 0 16px;
}

/* Tablet */
@media (min-width: 768px) {
  .container {
    padding: 0 24px;
    max-width: 720px;
    margin: 0 auto;
  }
}

/* Desktop */
@media (min-width: 1024px) {
  .container {
    max-width: 960px;
    padding: 0 32px;
  }
}