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HTML 

              
                
	
	<div class="custom-select-content-wrapper">
		<div class="custom-select-form-wrapper">
			
			<h1 class="custom-select-heading">Custom select box</h1>
			<form action="#">
				<fieldset>
					<select name="sources" id="sources" class="custom-select sources" data-placeholder="Select box">
						<option value="profile">Lorem ipsum dolor sit amet</option>
						<option value="word">	Consectetur adipisicing elit</option>
						<option value="hashtag">Lorem ipsum dolor sit amet consectetur adipisicing elit. Vitae unde voluptate cumque dolores quod veritatis repudiandae laborum eaque, corrupti architecto.</option>
					</select>
				</fieldset>
			</form>

		</div>
	</div>
	
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
!

CSS 

              
                /***PAGE STYLE (BEGIN)***/
* {
	margin: 0;
	padding: 0;
}

body {
	background-color: #efa602;
	font-family: 'Roboto', sans-serif;
	font-size: 16px;
}

.custom-select-content-wrapper {
	width: 100%;
	height: 100vh;
	background: #ffd700;
	background: -moz-linear-gradient(top,  #ffd700 0%, #efa602 100%);
	background: -webkit-linear-gradient(top,  #ffd700 0%,#efa602 100%);
	background: linear-gradient(to bottom,  #ffd700 0%,#efa602 100%);
	filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffd700', endColorstr='#efa602',GradientType=0 );
}

.custom-select-form-wrapper {
	position: relative;
	top: 50px;
	margin: 0 auto;
	padding: 0 2.5%;
	width: 32.5%;
	max-width: 650px;
	min-width: 400px;
	border-radius: 10px;
	border: 2px solid rgba(159,107,4,0.45);
	background-color: rgba(255,255,255,0.45);
	box-shadow: 0 10px 20px #bb9241;
}

.custom-select-heading {	
	margin: 50px 0;
	font-size: 3em;
	color: #fff;
	text-align: center;
	text-transform: uppercase;	
	text-shadow: 0 2px 1px #a9742b;
}
/***PAGE STYLE (END)***/

/***CUSTOM SELECT STYLE (BEGIN)***/
fieldset {
	border: none;
}

input[type="text"],
select,
textarea {
	width: 100%;
}

.custom-select-wrapper {
	position: relative;
	margin-bottom: 90px;
	display: block;
}

.custom-select-wrapper select {
	display: none;
	overflow: hidden;
	width: 100%;
}

.custom-select {
	position: relative;
	display: block;	
}

.custom-select-trigger {
	position: relative;	
	padding: 0;
	display: block;
	overflow: hidden;
	width: 100%;	
	border: 2px solid #dbb729;
	border-radius: 10px;
	background-color: #fff;
	font-size: 1.875em;
	line-height: 160%;
	color: #3e345c;
	cursor: pointer;
}

.custom-select-trigger:after {
	position: absolute;
	display: block;
	content: '';
	width: 10px;
	height: 10px;
	top: 50%;
	right: 20px;
	margin-top: -0.13636363em;
	border-bottom: 1px solid #84570a;
	border-right: 1px solid #84570a;
	-webkit-transform: rotate(45deg) translateY(-50%);
	-ms-transform: rotate(45deg) translateY(-50%);
	transform: rotate(45deg) translateY(-50%);
	-webkit-transition: all .4s ease-in-out;
	transition: all .4s ease-in-out;
	-webkit-transform-origin: 50% 0;
	-ms-transform-origin: 50% 0;
	transform-origin: 50% 0;
}

.custom-select.opened .custom-select-trigger:after {
	margin-top: 0.13636363em;
	-webkit-transform: rotate(-135deg) translateY(-50%);
	-ms-transform: rotate(-135deg) translateY(-50%);
	transform: rotate(-135deg) translateY(-50%);
}

.custom-select-trigger-text {
	position: relative;
	top: 0.4em;	
	padding: 0 45px 0 20px;
	display: inline-block;
	overflow: hidden;
	height: 57px;	
	color: #84570a;
}

.custom-options {
	position: absolute;
	top: 100%;
	right: 0;
	left: 0;
	margin: 0;
	display: none;
	min-width: 100%;	
	border: 1px solid #ececec;
	border-radius: 10px;
	-webkit-box-sizing: border-box;
	box-sizing: border-box;
	-webkit-box-shadow: 0 3px 2px rgba(0, 0, 0, 0.1);
	box-shadow: 0 3px 2px rgba(0, 0, 0, 0.1);
	background-color: #fff;
	-webkit-transition: all .4s ease-in-out;	
	opacity: 0;
	z-index: 10;
	transition: all .4s ease-in-out;
}

.custom-options:before {
	position: absolute;
	display: block;
	content: '';
	top: -0.22727272em;
	right: 25px;
	width: 7px;
	height: 7px;
	margin-bottom: -0.18181818em;
	border-top: 1px solid #ececec;
	border-left: 1px solid #ececec;
	background: #fff;
	-webkit-transform: rotate(45deg);
	-ms-transform: rotate(45deg);
	transform: rotate(45deg);
	-webkit-transition: all .4s ease-in-out;
	transition: all .4s ease-in-out;
}

.option-hover:before {
	background: #f9f9f9;
}

.custom-option {
	position: relative;
	display: block;
	padding: 10px;
	border-bottom: 1px solid #ececec;
	font-size: 1em;
	color: #333333;
	cursor: pointer;
	-webkit-transition: all .25s ease-in-out;
	transition: all .25s ease-in-out;
}

.custom-option:last-of-type {
	border-bottom: 0;
	border-radius: 10px;
}

.custom-option.selection:hover,
.custom-option:hover {
	background: #fff9e6;
}
/***CUSTOM SELECT STYLE (END)***/
!

JS 

              
                $(function(){

	var $customSelect = $( '.custom-select' );
	var $resetButton = $( '#resetButton' );


	$customSelect.each(function() {
		var classes = $( this ).attr( 'class' );
		var id = $( this ).attr( 'id' );
		var name = $( this ).attr( 'name' );

		var template =  '<div class="' + classes + '">';
		template += '<span class="custom-select-trigger">';
		template += '<span class="custom-select-trigger-text">' + $( this ).data( 'placeholder' ) + '</span>';
		template += '</span>';
		template += '<div class="custom-options">';

		$(this).find( 'option' ).each( function() {
			template += '<span class="custom-option" data-value="' + $( this ).attr( 'value' ) + '">' + $( this ).html() + '</span>';
		});

		template += '</div></div>';
		
		var customSelectWrapper = $( '<div class="custom-select-wrapper"></div>' );
		customSelectWrapper.css({
			'-webkit-user-select': 'none',
			'-moz-user-select': 'none',
			'-ms-user-select': 'none',
			'user-select': 'none'
		});

		$( this ).wrap( customSelectWrapper );
		$( this ).after( template );
	});


	$( document ).on( 'click', function( e ){
		var eTarget = e.target;

		if( !$( eTarget ).closest( '.custom-select-wrapper' ).hasClass( 'custom-select-wrapper' ) ) {
			$( '.custom-select' ).removeClass( 'opened' );
			customOptionsClosed();
		}
	});


	$( '.custom-select-trigger' ).on( 'click', function() {
		$( this ).parents( '.custom-select' ).toggleClass( 'opened' );

		var timer;
		if( $( this ).parents( '.custom-select' ).hasClass( 'opened' ) ){
			clearTimeout( timer );

			$( this )
				.parents( '.custom-select' )
				.find( '.custom-options' )
				.stop()
				.css('display', 'block')
				.animate({
					'opacity': '1',
					'margin-top': '15px'
				},100 );
		}

		else{
			customOptionsClosed();
		}

	});


	$( '.custom-option' ).on( 'click', function() {
		$( this ).parents( '.custom-select-wrapper' ).find( 'select' ).val( $( this ).data( 'value' ) );
		$( this ).parents( '.custom-options' ).find( '.custom-option' ).removeClass( 'selection' );
		$( this ).addClass( 'selection' );
		$( this ).parents( '.custom-select' ).removeClass( 'opened' );		
		$( this ).parents( '.custom-select' ).find( '.custom-select-trigger-text' ).text( $( this ).text() );
		customOptionsClosed();
	});


	$resetButton.on('click', function() {
		$( '.custom-select-trigger-text' ).text( $customSelect.data( 'placeholder' ) );
	});


	function customOptionsClosed() {
		$('.custom-options')
			.stop()
			.animate({
				opacity: 0,
				'margin-top': '0'
			},100 );

		t = setTimeout(function(){
			$('.custom-options').css('display', 'none');
		}, 500 );
	}

});
!
999px

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