p vertical align middle in div code example

Example 1: vertical align into div

#parent {position: relative;}

#child {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    width: 50%;
    height: 30%;
    margin: auto;
}

Example 2: vertical align text inside div

text {
  	line-height: 100px; /*size of parent div*/ 
}