discourse/app/assets/stylesheets/common/base/header.scss

.d-header {
    width: 100%;
    position: absolute;
    top: 0;
    z-index: 1001;
    background-color: $header_background;
    box-shadow: 0 2px 4px -1px rgba(0,0,0, .25);

    .docked & {
      position: fixed;
      backface-visibility: hidden;  /** do magic for scrolling performance **/
    }

    .contents {
      margin: 8px 0;
    }

    .title {
      float: left;
    }

    .valign-helper {
      display: inline-block;
      height: 100%;
      vertical-align: middle;
    }

    #site-logo {
      max-height: 40px;
    }

    .fa-home {
      font-size: 1.643em;
    }

    .panel {
      float: right;
      position: relative;
    }

    .login-button, button.sign-up-button {
      float: left;
      margin-top: 7px;
      padding: 6px 10px;
      .fa { margin-right: 3px; }
    }

    button.login-button {
      margin-left: 7px;
    }

    .icons {
      float: left;
      text-align: center;
      margin: 0 0 0 5px;
      list-style: none;

      > li {
        float: left;
      }
      .icon {
        display: block;
        padding: 3px;
        color: dark-light-choose(scale-color($header_primary, $lightness: 50%), $header_primary);
        text-decoration: none;
        cursor: pointer;
        border-top: 1px solid transparent;
        border-left: 1px solid transparent;
        border-right: 1px solid transparent;
        transition: all linear .15s;


        &:hover {
          color: $primary;
          background-color:  dark-light-diff($primary, $secondary, 90%, -60%);
          border-top: 1px solid transparent;
          border-left: 1px solid transparent;
          border-right: 1px solid transparent;
        }
        &:active {
          color: $primary;
          background-color: dark-light-diff($primary, $secondary, 90%, -60%);
        }
      }
      .active .icon {
        position: relative;
        color: #7b7b7b;
        background-color: $secondary;
        cursor: default;
        border-top: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
        border-left: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
        border-right: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
        &:after {
          display: block;
          position: absolute;
          top: 100%;
          left: 0;
          z-index: 1101;
          width: 100%;
          height: 0;
          content: "";
          border-top: 1px solid $secondary;
        }
        &:hover {
        border-bottom: none;
        }
      }
      [class^="fa fa-"] {
        width: 32px;
        height: 32px;
        font-size: 1.714em;
        line-height: 32px;
        display: inline-block;
      }
      .notifications {
        position: relative;
      }
      .badge-notification {
        position: absolute;
        top: -9px;
        z-index: 1;
        margin-left: 0;
      }
      .unread-notifications {
        right: -4px;
        background-color: scale-color($tertiary, $lightness: 50%);
      }
      .unread-private-messages {
        left: -4px;
      }
    }
    .flagged-posts {
      background: $danger;
    }
}

.d-dropdown {
    display: none;
    position: absolute;
    background: $secondary;
    max-height: 417px;
    top: 100%;
    right: 0;
    z-index: 1100;
    overflow: auto;
    border: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
    padding: 5px;

    box-shadow: 0 2px 2px rgba(0,0,0, .4);


  ul {
    margin: 0;
    list-style: none;
  }

  li:not(.category):not(.heading) {
    font-size: 0.929em;
    line-height: 16px;

      .fa {
        font-size: inherit;
      }

      a {
        display: block;
        padding: 5px;
        transition: all linear .15s;
      }

      &:hover a:not(.badge-notification) {
        background-color: dark-light-diff($highlight, $secondary, 50%, -55%);
        }

      button {margin-left: 5px;}
  }

  .heading a:hover  {
    background-color: dark-light-diff($highlight, $secondary, 50%, -55%);
  }

  .selected {
    background-color: dark-light-diff($tertiary, $secondary, 85%, -65%);
  }


  // Notifications
  &#notifications-dropdown {
    .fa { color: dark-light-choose(scale-color($primary, $lightness: 50%), scale-color($secondary, $lightness: 50%)); }
    .icon { color: dark-light-choose(scale-color($primary, $lightness: 30%), scale-color($secondary, $lightness: 70%)); }
    li {
      background-color: dark-light-diff($tertiary, $secondary, 85%, -65%);
      i {
        float: left;
        margin-right: 5px;
        padding-top: 2px;
      }
      span { color: $primary; }
      &:hover a { background-color: dark-light-diff($highlight, $secondary, 50%, -55%); }
      a { padding: 4px 0 3px 2px; }
      p {
        margin: 0;
        overflow: hidden;
      }
    }
    .is-warning {
      i.fa-envelope-o {
        &:before {
          content: "\f0e0";
        }
        color: $danger;
      }
    }
    .read {
      background-color: $secondary;
    }
    .none {
      padding: 5px;
    }
    .spinner {
      width: 20px;
      height: 20px;
      border-width: 2px;
      margin: 0 auto;
    }
    /* as a big ol' click target, don't let text inside be selected */
    @include unselectable;
  }

  // Search

  &#search-dropdown {
    .heading {
      padding: 5px 0 5px 5px;
    .filter {
      padding: 0 5px;
    }
     }
  }

  input[type='text'] {
    width: 518px;
    height: 22px;
    margin: 5px;
    padding: 5px;
  }

  .search-context {
    padding: 0 5px;
    label { margin-bottom: 0; }
  }

  .searching {
    position: absolute;
    top: 0;
    right: 0;
    .spinner {
      width: 10px;
      height: 10px;
      border-width: 2px;
      margin: 20px 0 0 0;
      }
  }
  // I am ghetto using this to display "Show More".. be warned
  .no-results {
    padding: 5px;
    text-align: center;
  }
  .filter {
    padding: 0;
    &:hover {background: transparent;}
  }

  // Categories

  &#user-dropdown {
    width: 118px;
  }

  .btn {
    padding: 2px 8px;
    margin-bottom: 2px;
    .fa {
      margin-right: 5px;
    }
  }
}

.search-link {
  .badge-category-parent {
    line-height: 0.8em;
  }
  .topic-title {
    margin-right: 6px;
  }

  .topic-statuses {
    float: none;
    display: inline-block;
    color: dark-light-choose(scale-color($primary, $lightness: 50%), scale-color($secondary, $lightness: 50%));
    margin: 0;
    .fa {
      margin: 0;
    }
  }
}

.highlight-strong {
  background-color: dark-light-diff($highlight, $secondary, 40%, -45%);
}

.search-highlight {
  font-weight: bold;
}

.search-context .show-help {
  position: absolute;
  right: 10px;
  top: 0;
}

.search-context {
  min-height: 30px;
  position: relative;
}

.d-dropdown#search-dropdown {
  max-height: none;
  overflow: inherit;
}

#search-dropdown .results {
  max-height: 300px;
  overflow: auto;
}

#search-help table td {
  padding-right: 10px;
}

// we don't need this X to clear field
#search-term::-ms-clear {
  display: none;
}