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HTML 

              
                <p>Using just CSS to style <code>&lt;select&gt;</code> elements, on a cross-browser way.</p>

<select>
	<option>Browser default styles</option>
	<option>Option 1</option>
	<option>Option 2</option>
</select>

<select class="select-basic">
	<option>Sass mixin basic styles</option>
	<option>Option 1</option>
	<option>Option 2</option>
</select>

<select class="select-full">
	<option>Sass mixin full styles</option>
	<option>Option 1</option>
	<option>Option 2</option>
</select>

<h2>See also:</h2>
<ul>
  <li>
    <a href="https://super-simple.net/blog/cross-browser-select-sass-mixin/#browser-support">
    Browser support
    </a>
  </li>
  <li>
    <a href="https://codepen.io/supersimplenet/pen/VwLmbYE">
      Progressive enhancement drop-down
    </a>
  </li>
</ul>

<h2>More info:</h2>

<ul>
  <li>
    <a href="https://www.filamentgroup.com/lab/select-css.html">
      Styling a Select Like It’s 2019
    </a>
  </li>
  <li>
    <a href="https://codepen.io/kevinweber/pen/dXWoRw?editors=0100">
      URL-encoded Inline SVG using SCSS mixin (no Base64 needed)
    </a>
  </li>
</ul>
!

CSS 

              
                // Sass utilities: https://codepen.io/supersimplenet/pen/xxZrZYa

@mixin select(
  $background: transparent,
  $caret: map-get($svg, angle-down),
  $caret-fill: null,
  $caret-width: .75em,
  $caret-background: transparent,
  $separator-width: 0px,
  $separator-color: transparent,
  $padding-y: .5rem,
  $padding-x: .5rem
){
  @content;
  
  -moz-appearance: none;
  -webkit-appearance: none;
  appearance: none;

  line-height: 1;
  cursor: pointer;
  
  &::-ms-expand {
    // Arrow icon in IE browsers
    display: none;
  }
 
  $padding-right: calc(#{$padding-x} + #{$separator-width} + #{$padding-x + #{$caret-width}} + #{$padding-x});

  @if ($caret-background == transparent and $separator-color == transparent and strip-unit($separator-width) == 0) {
    $padding-right: calc(#{$padding-x} + #{$separator-width} + #{$padding-x + #{$caret-width}});
  }

  @if ($caret-background == transparent) {
    $caret-background: linear-gradient(to bottom, transparent, transparent);
  }

  @if ($background == transparent) {
    $background: linear-gradient(to bottom, transparent, transparent);
  }

  @if ($separator-color == transparent) {
    $separator-color: linear-gradient(to bottom, transparent, transparent);
  }
    
  padding: $padding-y $padding-right $padding-y $padding-x;
  
  background-image:
    url(svg($caret, $caret-fill)),
    $caret-background,
    $separator-color,
    $background;
  background-repeat: no-repeat;
  background-position: 
    right $padding-x top 50%,
    right top,
    right calc(#{$padding-x} + #{$caret-width} + #{$padding-x}) top,
    right top;
  background-size:
    $caret-width 100%,
    calc(#{$padding-x} + #{$caret-width} + #{$padding-x}) 100%,
    $separator-width 100%,
    100%;
}

select {
  font: inherit;
  display: block;
  margin-bottom: 1rem;
  
  &.select-basic {
    @include select();
  }
  
  &.select-full {
    @include select(
      $background: linear-gradient(to bottom, #fff, #ddd),
      $caret: map-get($svg, caret-down),
      $caret-fill: #666,
      $caret-background: linear-gradient(to bottom, #eee, #ccc),
      $separator-width: 2px,
      $separator-color: linear-gradient(to bottom, #aaa, #aaa),
    ){
      border: 0;
      box-shadow: 0 0 5px gray;
      font-weight: bold;
      border-radius: .25em;
    };
  }
}
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JS
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