<header class="main-header">
    <div class="container">
      <nav class="navbar navbar-expand-lg main-nav px-0">
        <a class="navbar-brand" href="/mojo">
					      <img src="http://rajeshdas.com/assets/images/logo.svg" alt="rajeshdas.com">
					    </a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#mainMenu" aria-controls="mainMenu" aria-expanded="false" aria-label="Toggle navigation">
                        <span class="icon-bar icon-bar-1"></span>
                        <span class="icon-bar icon-bar-2"></span>
                        <span class="icon-bar icon-bar-3"></span>
                    </button>
        <div class="collapse navbar-collapse" id="mainMenu">
          <ul class="navbar-nav ml-auto text-uppercase f1">
            <li>
              <a href="#home" class="active active-first">home</a>
            </li>
            <li>
              <a href="#about">about us</a>
            </li>
            <li>
              <a href="#service">services</a>
            </li>
            <li>
              <a href="#project">projects</a>
            </li>
            <li>
              <a href="#team">team</a>
            </li>
            <li>
              <a href="#testimony">testimonils</a>
            </li>
            <li>
              <a href="#contact">contact</a>
            </li>
          </ul>
        </div>
      </nav>
    </div>
    <!-- /.container -->
  </header>
  
/**
 * index.scss
 * - Add any styles you want here!
 */

body {
  background: #2d2d7f !important;
}
/* main-header start */
[data-target="#mainMenu"] {
  position: relative;
  z-index: 999;
}

#mainMenu li > a {
  font-size: 12px;
  letter-spacing: 1px;
  color: #fff;
  font-weight: 400;
  position: relative;
  z-index: 1;
  text-decoration: none;
}

.main-header.fixed-nav #mainMenu li > a {
  color: #fff;
  text-decoration: none;
}

#mainMenu li:not(:last-of-type) {
  margin-right: 30px;
}

#mainMenu li > a::before {
  position: absolute;
  content: "";
  width: calc(100% - 1px);
  height: 1px;
  background: #fff;
  bottom: -6px;
  left: 0;

  -webkit-transform: scale(0, 1);
  -ms-transform: scale(0, 1);
  transform: scale(0, 1);
  -webkit-transform-origin: right center;
  -ms-transform-origin: right center;
  transform-origin: right center;
  z-index: -1;

  -webkit-transition: transform 0.5s ease;
  transition: transform 0.5s ease;
}

#mainMenu li > a:hover::before,
#mainMenu li > a.active::before {
  -webkit-transform: scale(1, 1);
  -ms-transform: scale(1, 1);
  transform: scale(1, 1);
  -webkit-transform-origin: left center;
  -ms-transform-origin: left center;
  transform-origin: left center;
}

.main-header.fixed-nav #mainMenu li > a::before {
  background: #000;
}

.main-header {
  position: fixed;
  top: 25px;
  left: 0;
  z-index: 99;
  width: 100%;
  -webkit-transition: all 0.4s ease;
  transition: all 0.4s ease;
}

.main-header.fixed-nav {
  top: 0;
  background: #fff;
  -webkit-box-shadow: 0 8px 12px -8px rgba(0, 0, 0, 0.09);
  box-shadow: 0 8px 12px -8px rgba(0, 0, 0, 0.09);
  -webkit-transition: all 0.4s ease;
  transition: all 0.4s ease;
}

.main-header.fixed-nav .navbar-brand > img:last-of-type {
  display: block;
}

.main-header.fixed-nav .navbar-brand > img:first-of-type {
  display: none;
}
.navbar-brand {
  color: #fff;
}
.main-header .navbar-brand img {
  max-width: 40px;
  animation: fadeInLeft 0.4s both 0.4s;
}
/* main-header end */
@media (max-width: 991px) {
  /*header starts*/
  .collapse.in {
    display: block !important;
    padding: 0;
    clear: both;
  }

  .navbar-toggler {
    margin: 0;
    padding: 0;
    width: 40px;
    height: 40px;
    position: absolute;
    top: 25px;
    right: 0;
    border: none;
    border-radius: 0;
    outline: none !important;
  }

  .main-header .navbar {
    float: none;
    width: 100%;
    padding-left: 0;
    padding-right: 0;
    text-align: center;
  }

  .main-header .navbar-nav {
    margin-top: 70px;
  }

  .main-header .navbar-nav li .nav-link {
    text-align: center;
    padding: 20px 15px;
    border-radius: 0px;
  }

  /**/
  .main-header .navbar-toggler .icon-bar {
    background-color: #fff;
    margin: 0 auto 6px;
    border-radius: 0;
    width: 30px;
    height: 3px;
    position: absolute;
    right: 0;
    -webkit-transition: all 0.2s ease;
    transition: all 0.2s ease;
  }

  .main-header .navbar .navbar-toggler .icon-bar:first-child {
    margin-top: 3px;
  }

  .main-header .navbar-toggler .icon-bar-1 {
    width: 10px;
    top: 0px;
  }

  .main-header .navbar-toggler .icon-bar-2 {
    width: 16px;
    top: 12px;
  }

  .main-header .navbar-toggler .icon-bar-3 {
    width: 20px;
    top: 21px;
  }

  .main-header .current .icon-bar {
    margin-bottom: 5px;
    border-radius: 0;
    display: block;
  }

  .main-header .current .icon-bar-1 {
    width: 18px;
  }

  .main-header .current .icon-bar-2 {
    width: 30px;
  }

  .main-header .current .icon-bar-3 {
    width: 10px;
  }

  .main-header .navbar-toggler:hover .icon-bar {
    background-color: #fff;
  }

  .main-header .navbar-toggler:focus .icon-bar {
    background-color: #fff;
  }

  /*header ends*/
}

External CSS

  1. https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js
  2. https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js
  3. https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js