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HTML 

              
                <!-- widget for container demo only, the rest matters -->
<form class="widget">
  
<div class="input-wrap">
  <input type="text" placeholder="CVC">
</div>
  
<div class="select">
  <select aria-label="Select menu example">
    <option selected>Open this select menu</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
  </select>
</div>
  
</form>
!

CSS 

              
                /*
 CREDIT / MOSTLY TAKEN FROM:
 http://wtfforms.com/wtf-forms.css
*/


/*
 * Select
 */

.select {
  position: relative;
  display: inline-block;
  width: 100%;
  color: #555;
}
.select select {
  display: inline-block;
  width: 100%;
  margin: 0;
  padding: .5rem 2.25rem .5rem 1rem;
  line-height: 1.5;
  color: #555;
  background-color: #eee;
  border: 0;
  border: 1px solid #D0D0D0;
  border-radius: .25rem;
  cursor: pointer;
  outline: 0;
  -webkit-appearance: none;
     -moz-appearance: none;
          appearance: none;
}
/* Undo the Firefox inner focus ring */
.select select:focus:-moz-focusring {
  color: transparent;
  text-shadow: 0 0 0 #000;
}
/* Dropdown arrow */
.select:after {
  position: absolute;
  top: 50%;
  right: 1.25rem;
  display: inline-block;
  content: "";
  width: 0;
  height: 0;
  margin-top: -.15rem;
  pointer-events: none;
  border-top: .35rem solid;
  border-right: .35rem solid transparent;
  border-bottom: .35rem solid transparent;
  border-left: .35rem solid transparent;
}

/* Hover state */
/* Uncomment if you need it, but be aware of the sticky iOS states.
.select select:hover {
  background-color: #ddd;
}
*/

/* Focus */
.select select:focus {
  box-shadow: 0 0 0 .075rem #fff, 0 0 0 .2rem #0074d9;
}

/* Active/open */
.select select:active {
  color: #fff;
  background-color: #0074d9;
}

/* Hide the arrow in IE10 and up */
.select select::-ms-expand {
  display: none;
}

/* Media query to target Firefox only */
@-moz-document url-prefix() {
  /* Firefox hack to hide the arrow */
  .select select {
    text-indent: 0.01px;
    text-overflow: '';
    padding-right: 1rem;
  }

  /* <option> elements inherit styles from <select>, so reset them. */
  .select option {
    background-color: white;
  }
}

/* IE9 hack to hide the arrow */
@media screen and (min-width:0\0) {
  .select select {
    z-index: 1;
    padding: .5rem 1.5rem .5rem 1rem;
  }
  .select:after {
    z-index: 5;
  }
  .select:before {
    position: absolute;
    top: 0;
    right: 1rem;
    bottom: 0;
    z-index: 2;
    content: "";
    display: block;
    width: 1.5rem;
    background-color: #eee;
  }
  .select select:hover,
  .select select:focus,
  .select select:active {
    color: #555;
    background-color: #eee;
  }
}


/* Input part is easier */
input[type="text"],
select {
  font-family: sans-serif;
  font-size: 15px;
}
.input-wrap {
  margin: 0 0 20px 0;
}
input[type="text"] {
  padding: 10px 15px;
  border-radius: 5px;
  border: 1px solid #D0D0D0;
  width: 100%;
  box-sizing: border-box; /* if you already aren't doing universally */
}




/* Doesn't matter */
body {
  background: #EBEDF1;
}
.widget {
  max-width: 400px;
  margin: 50px auto;
  background: #F3F3F3;
  padding: 20px;
  border: 1px solid #DCDCDC;
  border-radius: 5px;
}
!

JS
!
999px

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