tabler/scss/layout/_navbar.scss

.navbar {
  border-bottom: 1px solid;

  background-color: $navbar-bg;
  border-color: $navbar-border-color;

  .nav-link {
    color: inherit;
    white-space: nowrap;
  }
}

.navbar-nav {
  flex-direction: row;
  margin-right: -($navbar-padding-x);
  margin-left: -($navbar-padding-x);

  .nav-link {
    display: flex;
    color: $text-muted;
    transition: .3s color;

    &:hover {
      color: $body-color;
    }
  }

  .nav-item {
    position: relative;
  }

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

.navbar:not(.navbar-side) .navbar-subnav {
  position: absolute;
  top: 100%;
  left: 0;
  z-index: $zindex-tooltip;
  width: 12rem;
  padding: .25rem;
  font-size: $h5-font-size;
  background: #fff;
  border: 1px solid $border-color;
  border-radius: 3px;
  box-shadow: 0 .5rem 1rem rgba(18, 18, 18, .15);

  .nav {
    flex-direction: column;
  }
}

/**
Navbar brand
 */
.navbar-brand {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  margin: 0;

  @at-root a#{&} {
    transition: .3s opacity;

    &:hover {
      opacity: .8;
    }
  }
}

.navbar-brand-logo {
  height: 2rem;
}

/**
Navbar toggler
 */
.navbar-toggler {
  padding: 0;
  border: 0;
}

/*
Sidebar
 */
.navbar-side {
  flex-direction: column;
  flex-wrap: nowrap;
  align-items: inherit;
  justify-content: start;
  width: $sidenav-width;
  min-width: $sidenav-width;
  margin: 0;
  overflow: auto;
  pointer-events: inherit;
  user-select: none;
  background: $sidenav-bg;
  border-right: 1px solid $sidenav-border-color;

  .nav {
    flex-direction: column;
  }

  .nav-link {
    display: flex;
    align-items: center;
    height: 2.5rem;
    padding: 0 $navbar-padding-x;
    color: $text-muted;
    box-shadow: inset 2px 0 0 0 transparent;
    transition: .3s background, .3s box-shadow;

    &[aria-expanded="true"],
    &:hover {
      background: rgba($link-color, .04);
      border-color: $primary;
      box-shadow: inset 2px 0 0 0 $primary;
    }

    > .icon {
      width: 2rem;
    }

    &[data-toggle="collapse"] {
      &::after {
        display: block;
        margin-left: auto;
        font-family: $font-icons !important;
        content: "";
        transition: transform .3s;
      }

      &[aria-expanded="true"]::after {
        transform: rotate(-180deg);
      }
    }
  }

  &:not(.navbar-folded) {
    &[data-toggle="collapse"][aria-expanded="true"] {
      background: none;
      box-shadow: none;
    }
  }

  &:not(.hide-navbar-folded) {
    //.nav-item .nav-item .nav-link {
    //  padding-left: 2.5rem;
    //}
    //
    //.nav-item .nav-item .nav-item .nav-link {
    //  padding-left: 3.5rem;
    //}
    //
    //.nav-item .nav-item .nav-item .nav-item .nav-link {
    //  padding-left: 4.5rem;
    //}
  }

  .navbar-brand {
    height: 2.5rem;
    text-align: center;
  }

  .navbar-heading {
    @extend .subheader;
    margin: 0 0 .5rem;
  }

  .navbar-nav {
    flex-direction: column;
  }
}

/*
Fixed navbar
 */
.navbar-fixed {
  position: fixed;
  top: 0;
  bottom: 0;
  z-index: $zindex-sticky;

  + .navbar-bg {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: $zindex-dropdown;
    display: none;
    background: rgba($dark, .2);
  }

  &.navbar-side {
    top: 0;
    bottom: 0;
    left: 0;

    &.navbar-right {
      right: 0;
      left: auto;
    }
  }
}

.navbar-side {
  display: none;

  @include media-breakpoint-up(xl) {
    display: flex;

    &.navbar-fixed {
      & ~ .layout-main {
        margin-left: $sidenav-width;
      }

      &.navbar-right ~ .layout-main {
        margin-right: $sidenav-width;
        margin-left: 0;
      }
    }
  }

  &.navbar-folded {
    display: flex;

    &.navbar-fixed {
      @include media-breakpoint-up(lg) {

        & ~ .layout-main {
          margin-left: $sidenav-folded-width;
        }

        &.navbar-right ~ .layout-main {
          margin-right: $sidenav-folded-width;
          margin-left: 0;
        }
      }
    }
  }
}

/*
Right navbar
 */
.navbar-right {
  order: 9;
  border-right: none;
  border-left: 1px solid $sidenav-border-color;
}

/*
Dark navbar
 */
.navbar-dark {
  color: #fff;
  background-color: $sidenav-dark-bg;

  .navbar-brand {
    filter: brightness(0) invert(1);
  }

  .navbar-divider {
    border-color: rgba(#fff, .2);
  }

  .nav-link {
    color: inherit;
  }
}

/**
Sticky navbar
 */
.navbar-sticky {
  position: sticky;
  top: 0;
  z-index: 100;

  &.navbar-side {
    left: 0;
  }
}

/**
Folded navbar
 */
.navbar-folded {
  width: $sidenav-folded-width;
  min-width: $sidenav-folded-width;

  .navbar-brand {
    width: 2.5rem;
  }

  .navbar-heading {
    display: none;
  }

  .nav-text {
    display: none;
  }

  .nav-link {
    justify-content: center;
    padding-top: 0;
    padding-bottom: 0;

    &[data-toggle="collapse"]::after {
      content: none;
    }
  }

  .nav-icon {
    justify-content: center;
    opacity: 1;
  }

  .navbar-subnav {
    position: absolute;
    top: 0;
    left: 100%;
    background: #fff;

    .nav-text {
      display: block;
    }

    .nav-link {
      color: $body-color;
    }
  }
}

.nav-icon {
  display: flex;
  flex-shrink: 0;
  align-items: center;
  width: 1.5rem;
  font-size: px2rem(15px);
  border-radius: 100%;
  opacity: .8;

  .icon {
    font-size: inherit;
  }
}

.nav-text {
  display: flex;
  align-items: center;
  width: 100%;
}

/**
Utils
 */
.hide-navbar-folded {
  @at-root .navbar-side.navbar-folded & {
    display: none;
  }
}

.hide-navbar-expanded {
  @at-root .navbar-side:not(.navbar-folded) & {
    display: none;
  }
}