Bootstrap/scss/_navbar.scss

// Wrapper and base class
//
// Provide a static navbar from which we expand to create full-width, fixed, and
// other navbar variations.

.navbar {
  position: relative;
  display: flex;
  padding: $navbar-padding-y $navbar-padding-x;
}

.navbar-toggler-left {
  position: absolute;
  left: $navbar-padding-x;
}

.navbar-toggler-right {
  position: absolute;
  right: $navbar-padding-x;
}


// Navbar alignment options
//
// Display the navbar across the entirety of the page or fixed it to the top or
// bottom of the page.

// Fix the top/bottom navbars when screen real estate supports it
.navbar-fixed-top,
.navbar-fixed-bottom {
  position: fixed;
  right: 0;
  left: 0;
  z-index: $zindex-navbar-fixed;
}

.navbar-fixed-top {
  top: 0;
}

.navbar-fixed-bottom {
  bottom: 0;
}

.navbar-sticky-top {
  position: sticky;
  top: 0;
  z-index: $zindex-navbar-sticky;
}


//
// Brand/project name
//

.navbar-brand {
  display: inline-block;
  padding-top: .25rem;
  padding-bottom: .25rem;
  margin-right: $navbar-padding-x;
  font-size: $font-size-lg;
  line-height: inherit;
  white-space: nowrap;

  @include hover-focus {
    text-decoration: none;
  }
}

.navbar-divider {
  float: left;
  width: $border-width;
  padding-top: $navbar-divider-padding-y;
  padding-bottom: $navbar-divider-padding-y;
  margin-right: $navbar-padding-x;
  margin-left:  $navbar-padding-x;
  overflow: hidden;

  &::before {
    content: "\00a0";
  }
}


// Navbar text
//
//

.navbar-text {
  display: inline-block;
  padding-top:    .425rem;
  padding-bottom: .425rem;
}


// Navbar toggle
//
// Custom button for toggling the `.navbar-collapse`, powered by the collapse
// Bootstrap JavaScript plugin.

.navbar-toggler {
  padding: $navbar-toggler-padding-y $navbar-toggler-padding-x;
  font-size: $navbar-toggler-font-size;
  line-height: 1;
  background: transparent; // remove default button style
  border: $border-width solid transparent; // remove default button style
  @include border-radius($navbar-toggler-border-radius);

  @include hover-focus {
    text-decoration: none;
  }
}

// Keep as a separate element so folks can easily override it with another icon
// or image file as needed.
.navbar-toggler-icon {
  display: inline-block;
  width: 1.5em;
  height: 1.5em;
  vertical-align: middle;
  content: "";
  background: no-repeat center center;
  background-size: 100% 100%;
}

// Navigation
//
// Custom navbar navigation built on the base `.nav` styles.

.navbar-nav {
  flex-grow: 10; // high number to force alignment

  .nav-link {
    display: block;
    padding-top: .425rem;
    padding-bottom: .425rem;
  }
}


// Dark links against a light background
.navbar-light {
  .navbar-brand,
  .navbar-toggler {
    color: $navbar-light-active-color;

    @include hover-focus {
      color: $navbar-light-active-color;
    }
  }

  .navbar-nav {
    .nav-link {
      color: $navbar-light-color;

      @include hover-focus {
        color: $navbar-light-hover-color;
      }

      &.disabled {
        color: $navbar-light-disabled-color;
      }
    }

    .open > .nav-link,
    .active > .nav-link,
    .nav-link.open,
    .nav-link.active {
      @include plain-hover-focus {
        color: $navbar-light-active-color;
      }
    }
  }

  .navbar-toggler {
    border-color: $navbar-light-toggler-border;
  }

  .navbar-toggler-icon {
    background-image: $navbar-light-toggler-bg;
  }

  .navbar-divider {
    background-color: rgba(0,0,0,.075);
  }

  .navbar-text {
    color: $navbar-light-color;
  }
}

// White links against a dark background
.navbar-inverse {
  .navbar-brand,
  .navbar-toggler {
    color: $navbar-inverse-active-color;

    @include hover-focus {
      color: $navbar-inverse-active-color;
    }
  }

  .navbar-nav {
    .nav-link {
      color: $navbar-inverse-color;

      @include hover-focus {
        color: $navbar-inverse-hover-color;
      }

      &.disabled {
        color: $navbar-inverse-disabled-color;
      }
    }

    .open > .nav-link,
    .active > .nav-link,
    .nav-link.open,
    .nav-link.active {
      @include plain-hover-focus {
        color: $navbar-inverse-active-color;
      }
    }
  }

  .navbar-toggler {
    border-color: $navbar-inverse-toggler-border;
  }

  .navbar-toggler-icon {
    background-image: $navbar-inverse-toggler-bg;
  }

  .navbar-divider {
    background-color: rgba(255,255,255,.075);
  }

  .navbar-text {
    color: $navbar-inverse-color;
  }
}

// Navbar toggleable
//
// Custom override for collapse plugin in navbar.

// Placed at the end of the file so it can override some CSS properties
// scss-lint:disable ImportantRule
.navbar-toggleable {
  @each $breakpoint in map-keys($grid-breakpoints) {
    $next: breakpoint-next($breakpoint, $grid-breakpoints);
    $infix: breakpoint-infix($breakpoint, $grid-breakpoints);
    &#{$infix} {
      @include media-breakpoint-down($breakpoint) {
        .navbar-nav {
          .dropdown-menu {
            position: static;
            float: none;
          }
        }

        > .container {
          padding-right: 0;
          padding-left: 0;
        }
      }

      @include media-breakpoint-up($next) {
        display: flex;
        flex-wrap: nowrap;
        align-items: center;

        // For nesting containers, have to redeclare for alignment purposes
        > .container {
          display: flex;
          flex-wrap: nowrap;
          align-items: center;
        }

        .navbar-collapse {
          display: flex !important;
          width: 100%;
        }

        .nav-item {
          display: inline-block;
        }

        .nav-link {
          padding-right: .5rem;
          padding-left: .5rem;
        }

        .navbar-toggler {
          display: none;
        }
      }
    }
  }
}
// scss-lint:enable ImportantRule