blue navbar in bootstrap code example

Example 1: bootstrap 4 navbar

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">Navbar</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>

  <div class="collapse navbar-collapse" id="navbarSupportedContent">
    <ul class="navbar-nav mr-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
          Dropdown
        </a>
        <div class="dropdown-menu" aria-labelledby="navbarDropdown">
          <a class="dropdown-item" href="#">Action</a>
          <a class="dropdown-item" href="#">Another action</a>
          <div class="dropdown-divider"></div>
          <a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#">Disabled</a>
      </li>
    </ul>
    <form class="form-inline my-2 my-lg-0">
      <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
      <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
    </form>
  </div>
</nav>

Example 2: nav bootstrap

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">Navbar</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#">Disabled</a>
      </li>
    </ul>
  </div>
</nav>

Example 3: changing navbar color bootstrap

$bgDefault   : #e74c3c;
$bgHighlight : #c0392b;
$colDefault  : #ecf0f1;
$colHighlight: #ffbbbc;
.navbar-default {
  background-color: $bgDefault;
  border-color: $bgHighlight;
  .navbar-brand {
    color: $colDefault;
    &:hover, &:focus {
      color: $colHighlight; }}
  .navbar-text {
    color: $colDefault; }
  .navbar-nav {
    > li {
      > a {
        color: $colDefault;
        &:hover,  &:focus {
          color: $colHighlight; }}}
    > .active {
      > a, > a:hover, > a:focus {
        color: $colHighlight;
        background-color: $bgHighlight; }}
    > .open {
      > a, > a:hover, > a:focus {
        color: $colHighlight;
        background-color: $bgHighlight; }}}
  .navbar-toggle {
    border-color: $bgHighlight;
    &:hover, &:focus {
      background-color: $bgHighlight; }
    .icon-bar {
      background-color: $colDefault; }}
  .navbar-collapse,
  .navbar-form {
    border-color: $colDefault; }
  .navbar-link {
    color: $colDefault;
    &:hover {
      color: $colHighlight; }}}
@media (max-width: 767px) {
  .navbar-default .navbar-nav .open .dropdown-menu {
    > li > a {
      color: $colDefault;
      &:hover, &:focus {
        color: $colHighlight; }}
    > .active {
      > a, > a:hover, > a:focus, {
        color: $colHighlight;
        background-color: $bgHighlight; }}}
}