opaque filter css code example

Example 1: css how to make background transparent

/* Use RGBA */
background-color: rgba(255, 255, 0, 0.75); /* Transparent Yellow */

Example 2: css opacity example

.opacity30 {
  opacity: 0.3;
  filter: alpha(opacity=30); /* For IE8 and earlier */
}

Example 3: css opacity from 0 to 1

@keyframes fadein {
    from { opacity: 0; }
    to { opacity: 1; }
}