discourse/app/assets/stylesheets/mobile/header.scss

// --------------------------------------------------
// Discourse header
// --------------------------------------------------

.d-header {

  #site-logo {
    max-width: 135px;
  }

  // some protection for text-only site titles
  .title {
    max-width: 140px;
    height: 39px;
    overflow: hidden;
    padding: 0;
    text-overflow: clip;
  }

  .icons {
    .badge-notification {
      color: $secondary;
    }

    .active .icon {
      &:after { margin-top: -1px; }
    }
  }

  button.sign-up-button {
    display:none;
  }
}

#main-outlet {
  padding-top: 60px;
}

// Dropdowns
// --------------------------------------------------

.d-dropdown {
  width: 290px;
  margin-top: -1px;

  // Common

  .heading {
    color: $primary;
    font-weight: bold;
    font-size: 0.857em;
    line-height: 15px;
  }

  // Search

  .searching {
    position: absolute;
    top: 0;
    right: 25px;
  }

  input[type='text'] {
    width: 265px;
    font-size: 1.143em;
  }

  &#user-dropdown {
    width: 155px;
  }

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

.search-link .badge-category {
  display: none;
}

.search-link .topic-statuses .topic-status i {
  font-size: 1em;
}

.d-dropdown#search-dropdown .heading {
  padding: 0;
}