how to make a transparent navbar visible when scrolling

Here you go:

$(window).scroll(function() {
  if ($(window).scrollTop() >= 50) {
    $('.navbar').css('background', 'red');
  } else {
    $('.navbar').css('background', 'transparent');
  }
});

Working Demo


You can add or remove a .transparent class to the nav according to the position of scrollbar.

$(window).scroll(function() {
  if ($(document).scrollTop() > 50) {
    $('nav').addClass('transparent');
  } else {
    $('nav').removeClass('transparent');
  }
});

and CSS:

nav.navbar{
   -webkit-transition: all 0.4s ease;
   transition: all 0.4s ease;
}

nav.navbar-inverse {
    background-color: #222;
    border-color: #080808;
}

nav.navbar.transparent {
  background-color:rgba(0,0,0,0);
}

Here is the solution with your code: http://jsfiddle.net/m7yww8oa/157/


When $(window).scroll check if $(window).scrollTop() greater than 50px. If so, add class .trans and remove it if doesn't.

Add the style

.navbar.trans {
   background:transparent !important;   
}

To your css.

Your working code:

$(window).scroll(function() {
  var offset = $(window).scrollTop();
  console.log(offset);
  $('.navbar').toggleClass('trans', offset > 50);
});
html, body {
  margin:0; 
  padding:0;
}

body {
  position:relative;
  height:200px;
}

.nav {
  margin:0px;	
}

.navbar{
  background:transparent;
  background-color:transparent;
  border-color:transparent;
  margin-bottom:0px;
  font-family: 'Droid Serif', serif;
  font-size:20px;
}

.navbar-brand {
  font-size:20px;
  font-family: 'Droid Serif', serif;
}

header {
  text-align: center;
  color: #fff;
  background-attachment: scroll;
  background-image: url("work.jpg");
  background-position: center center;
  background-repeat: none;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  background-size: cover;
  -o-background-size: cover;
}

header .intro-text {
  padding-top: 100px;
  padding-bottom: 50px;
}

header .intro-text .intro-heading {
  margin-bottom: 25px;
  text-transform: uppercase;
  font-family: Montserrat,"Helvetica Neue",Helvetica,Arial,sans-serif;
  font-size: 50px;
  font-weight: 700;
  line-height: 50px;
}

@media(min-width:768px) {
  header .intro-text {
    padding-top: 300px;
    padding-bottom: 200px;
  }

  header .intro-text .intro-heading {
    margin-bottom: 50px;
    text-transform: uppercase;
    font-family: Montserrat,"Helvetica Neue",Helvetica,Arial,sans-serif;
    font-size: 75px;
    font-weight: 700;
    line-height: 75px;
  }
}

.navbar.trans {
  background:transparent !important;  
}
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