Generated by SassMeister.com.

SassMeister-input-HTML.haml

%ul.dropdown
  %li.dropdown__item.dropdown__item--active
    %a.dropdown__link{:href => '#'} Hello?
    %ul.dropdown__menu
      %li.dropdown__menu-item
        %a.dropdown__menu-link{:href => '#'} Option 1
      %li.dropdown__menu-item
        %a.dropdown__menu-link{:href => '#'} Option 2
      %li.dropdown__menu-item
        %a.dropdown__menu-link{:href => '#'} Option 3

SassMeister-input.sass

// ----
// Sass (v3.3.4)
// Compass (v1.0.0.alpha.18)
// ----

*
  box-sizing: border-box

body
  font-family: "Helvetica Neue"

a
  text-decoration: none

.dropdown, .dropdown__menu
  list-style: none
  margin: 0
  padding: 0

.dropdown__item
  padding: 0.5rem 1.5rem
  position: relative
  text-align: center
  width: 100px

.dropdown__item--active
  .dropdown__menu
    display: block

.dropdown__menu
  border-radius: 4px
  border: 1px solid #edeeee
  display: none
  left: 0
  position: absolute
  top: 100%

.dropdown__menu-item
  border-bottom: 1px solid #edeeee
  padding: 0.5rem 1.5rem
  min-width: 7.5em

  &:last-child
    border: none
  

SassMeister-output.css

* {
  box-sizing: border-box;
}

body {
  font-family: "Helvetica Neue";
}

a {
  text-decoration: none;
}

.dropdown, .dropdown__menu {
  list-style: none;
  margin: 0;
  padding: 0;
}

.dropdown__item {
  padding: 0.5rem 1.5rem;
  position: relative;
  text-align: center;
  width: 100px;
}

.dropdown__item--active .dropdown__menu {
  display: block;
}

.dropdown__menu {
  border-radius: 4px;
  border: 1px solid #edeeee;
  display: none;
  left: 0;
  position: absolute;
  top: 100%;
}

.dropdown__menu-item {
  border-bottom: 1px solid #edeeee;
  padding: 0.5rem 1.5rem;
  min-width: 7.5em;
}
.dropdown__menu-item:last-child {
  border: none;
}

SassMeister-rendered.html

<ul class='dropdown'>
  <li class='dropdown__item dropdown__item--active'>
    <a class='dropdown__link' href='#'>Hello?</a>
    <ul class='dropdown__menu'>
      <li class='dropdown__menu-item'>
        <a class='dropdown__menu-link' href='#'>Option 1</a>
      </li>
      <li class='dropdown__menu-item'>
        <a class='dropdown__menu-link' href='#'>Option 2</a>
      </li>
      <li class='dropdown__menu-item'>
        <a class='dropdown__menu-link' href='#'>Option 3</a>
      </li>
    </ul>
  </li>
</ul>