js nth child code example

Example 1: javascript get element nth child

//you can use the css nth-child property like this:
var second-child = document.querySeletorAll('[your element name]:nth-child(2)');

Example 2: how to get the nth child of dom js

var c = document.getElementById("myDIV").childNodes;
  c[1].style.backgroundColor = "yellow";//first child
  c[2].style.backgroundColor = "red";//second child
  c[-1].style.backgroundColor = "green";//last child
  c[-2].style.backgroundColor = "blue";//secound last child

Example 3: css nth-child

/* Select the first list item */
li:nth-child(1) { }
/* Select odd list items */
li:nth-child(odd) { }
/* Select even list items */
li:nth-child(even) { }
/* Select each list item every 3 (3,6,9...) */
li:nth-child(3n) { }
/* Select each list item every 3 starting from the fourth (4,7,10...) */
li:nth-child(3n+1) { }