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CSS

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JavaScript

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HTML 

              
                <div class="sel sel--black-panther">
  <select name="select-profession" id="select-profession">
    <option value="" disabled>Profession</option>
    <option value="hacker">Hacker</option>
    <option value="gamer">Gamer</option>
    <option value="developer">Developer</option>
    <option value="programmer">Programmer</option>
    <option value="designer">Designer</option>
  </select>
</div>

<hr class="rule">

<div class="sel sel--superman">
  <select name="select-superpower" id="select-superpower">
    <option value="" disabled>Superpower</option>
    <option value="hacker">Power</option>
    <option value="gamer">Speed</option>
    <option value="developer">Acrobatics</option>
    <option value="programmer">Accuracy</option>
  </select>
</div>

<!--
  <span class="sel__placeholder sel__placeholder--black-panther">Placeholder Text</span>
  <div class="sel__box sel__box--black-panther">
    <span data-option="option_1" class="sel__box__options sel__box__options--black-panther">Option 1</span>
    <span data-option="option_2" class="sel__box__options sel__box__options--black-panther">Option 2</span>
    <span data-option="option_3" class="sel__box__options sel__box__options--black-panther">Option 3</span>
    <span data-option="option_4" class="sel__box__options sel__box__options--black-panther">Option 4</span>
    <span data-option="option_5" class="sel__box__options sel__box__options--black-panther">Option 5</span>
  </div>
-->

<!--
  .not-active.selected = hide
  .active.selected = show
-->
!

CSS 

              
                /* ===== Resets and Housekeeping ===== */
* {
  padding: 0;
  margin: 0;
}

html {
  font-size: 16px;
}

body {
  background: #eeebe7;
  padding: 100px 20px;
  text-align: center;
}

/* ===== Actual Styles ===== */

/* ===== Horizontal Rule ===== */
.rule {
  margin: 10px 0;
  border: none;
  height: 1.5px;
  background-image: linear-gradient(left, #f0f0f0, #c9bbae, #f0f0f0);
}

/* ===== Select Box ===== */
.sel {
  font-size: 1rem;
  display: inline-block;
  margin: 3em 2em;
  width: 350px;
  background-color: transparent;
  position: relative;
  cursor: pointer;
}

.sel::before {
  position: absolute;
  content: '\f063';
  font-family: 'FontAwesome';
  font-size: 2em;
  color: #FFF;
  right: 20px;
  top: calc(50% - 0.5em);
}

.sel.active::before {
  transform: rotateX(-180deg);
}

.sel__placeholder {
  display: block;
  font-family: 'Quicksand';
  font-size: 2.3em;
  color: #838e95;
  padding: 0.2em 0.5em;
  text-align: left;
  pointer-events: none;
  user-select: none;
  visibility: visible;
}

.sel.active .sel__placeholder {
  visibility: hidden;
}

.sel__placeholder::before {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 0.2em 0.5em;
  content: attr(data-placeholder);
  visibility: hidden;
}

.sel.active .sel__placeholder::before {
  visibility: visible;
}

.sel__box {
  position: absolute;
  top: calc(100% + 4px);
  left: -4px;
  display: none;
  list-style-type: none;
  text-align: left;
  font-size: 1em;
  background-color: #FFF;
  width: calc(100% + 8px);
  box-sizing: border-box;
}

.sel.active .sel__box {
  display: block;
  animation: fadeInUp 500ms;
}

.sel__box__options {
  display: list-item;
  font-family: 'Quicksand';
  font-size: 1.5em;
  color: #838e95;
  padding: 0.5em 1em;
  user-select: none;
}

.sel__box__options::after {
  content: '\f00c';
  font-family: 'FontAwesome';
  font-size: 0.5em;
  margin-left: 5px;
  display: none;
}

.sel__box__options.selected::after {
  display: inline;
}

.sel__box__options:hover {
  background-color: #ebedef;
}

/* ----- Select Box Black Panther ----- */
.sel {
  border-bottom: 4px solid rgba(0, 0, 0, 0.3);
}

.sel--black-panther {
  z-index: 3;
}

/* ----- Select Box Superman ----- */
.sel--superman {
/*   display: none; */
  z-index: 2;
}

/* ===== Keyframes ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translate3d(0, 20px, 0);
  }

  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes fadeOut {
  from {
    opacity: 1;
  }

  to {
    opacity: 0;
  }
}
!

JS 

              
                /* ===== Logic for creating fake Select Boxes ===== */
$('.sel').each(function() {
  $(this).children('select').css('display', 'none');
  
  var $current = $(this);
  
  $(this).find('option').each(function(i) {
    if (i == 0) {
      $current.prepend($('<div>', {
        class: $current.attr('class').replace(/sel/g, 'sel__box')
      }));
      
      var placeholder = $(this).text();
      $current.prepend($('<span>', {
        class: $current.attr('class').replace(/sel/g, 'sel__placeholder'),
        text: placeholder,
        'data-placeholder': placeholder
      }));
      
      return;
    }
    
    $current.children('div').append($('<span>', {
      class: $current.attr('class').replace(/sel/g, 'sel__box__options'),
      text: $(this).text()
    }));
  });
});

// Toggling the `.active` state on the `.sel`.
$('.sel').click(function() {
  $(this).toggleClass('active');
});

// Toggling the `.selected` state on the options.
$('.sel__box__options').click(function() {
  var txt = $(this).text();
  var index = $(this).index();
  
  $(this).siblings('.sel__box__options').removeClass('selected');
  $(this).addClass('selected');
  
  var $currentSel = $(this).closest('.sel');
  $currentSel.children('.sel__placeholder').text(txt);
  $currentSel.children('select').prop('selectedIndex', index + 1);
});
!
999px

Console