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HTML 

              
                mixin SelectBox(name, options)
  .select-box
    .select-box__current(tabindex="1")
      each option, index in options
        .select-box__value
          input.select-box__input(type="radio" id=index value=option.value name=name checked=option.checked)
          p.select-box__input-text #{option.name}
      img.select-box__icon(src="http://cdn.onlinewebfonts.com/svg/img_295694.svg" alt="Arrow Icon" aria-hidden="true")
    ul.select-box__list
      each option, index in options
        li
          label.select-box__option(for=index aria-hidden) #{option.name}
        
+SelectBox('Ben', [
  {name: 'Cream', value: '1', checked: true}, 
  {name: 'Cheese', value: '2'}, 
  {name: 'Milk', value: '3'}, 
  {name: 'Honey', value: '4'}, 
  {name: 'Toast', value: '5'}
])
!

CSS 

              
                html,
body {
  min-height: 100%;
  margin: 0;
}

body {
  padding: 30px;
  background-image: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  box-sizing: border-box;
}

.select-box {
  position: relative;
  display: block;
  width: 100%;
  margin: 0 auto;
  font-family: 'Open Sans', 'Helvetica Neue', 'Segoe UI', 'Calibri', 'Arial', sans-serif;
  font-size: 18px;
  color: #60666d;
  
  @media (min-width: 768px) {
    width: 70%;
  }
  
  @media (min-width: 992px) {
    width: 50%;
  }
  
  @media (min-width: 1200px) {
    width: 30%;
  }
  
  &__current {
    position: relative;
    box-shadow: 0 15px 30px -10px transparentize(#000, 0.9);
    cursor: pointer;
    outline: none;
    
    &:focus {
      & + .select-box__list {
        opacity: 1;

        // We have to set "animation-name: none;" to make the list visible (read below how it works)

        animation-name: none;
        
        .select-box__option {
          cursor: pointer;
        }
      }
      
      .select-box__icon {
        transform: translateY(-50%) rotate(180deg);
      }
    }
  }
  
  &__icon {
    position: absolute;
    top: 50%;
    right: 15px;
    transform: translateY(-50%);
    width: 20px;
    opacity: 0.3;
    transition: 0.2s ease;
  }
  
  &__value {
    display: flex;
  }
  
  &__input {
    display: none;
    
    &:checked + .select-box__input-text {
      display: block;
    }
  }
  
  &__input-text {
    display: none;
    width: 100%;
    margin: 0;
    padding: 15px;
    background-color: #fff;
  }
  
  &__list {
    position: absolute;
    width: 100%;
    padding: 0;
    list-style: none;
    opacity: 0;
    
    // We need to use animation with delay.
    // Otherwise the click event will not have time to run on label, because this element disapears immediately when .select-box__current element loses the focus.
    // This delay will not be noticed because we set "opacity" to "0".
    // We also use "animation-fill-mode: forwards" to make the list stay hidden.
    
    animation-name: HideList;
    animation-duration: 0.5s;
    animation-delay: 0.5s;
    animation-fill-mode: forwards;
    animation-timing-function: step-start;
    box-shadow: 0 15px 30px -10px transparentize(#000, 0.9);
  }
  
  &__option {
    display: block;
    padding: 15px;
    background-color: #fff;
    
    &:hover,
    &:focus {
      color: #546c84;
      background-color: #fbfbfb;
    }
  }
}

@keyframes HideList {
  from {
    transform: scaleY(1);
  }
  to {
    transform: scaleY(0);
  }
}
!

JS 

              
                // Pure CSS Select Box //
!
999px

Console