Example link >>> http://www.webtricker.com/projects/Samsara-v3/

Increase and Decrease Function in css with jQuery.js

//  This is One way 
var delayTime =  0.3
        
$('.nav-wrap ul li').each(function(a){
    var thisDelay = delayTime * a
    thisDelay = thisDelay + "s"
    $(this).css({
        "transition-delay" : thisDelay,
        //"opacity" : 1
    })

})
        
// This is another way 
  var delayTime =  0.3
  $('.nav-wrap ul li').each(function(i){
      $(this).css({
          "transition-delay" : delayTime *i+ "s",
      })

  })


// Another way with reverse 
$("#main-nav-wrap .main-nav li").each(function(i){
    var delayCounter = i+1

    $(this).css({
        "transition-delay" : 150*delayCounter+"ms"
    })
})

var totalElmntCount = $(".main-nav li").length 

$("#main-nav-wrap.navActive .main-nav li").each(function(i){

    var delayCounter = 150*(totalElmntCount-(i+1))

    $(this).css({
        "transition-delay" : delayCounter+"ms"
    })
})