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CSS

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CSS Base

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JavaScript

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HTML 

              
                <div class="code-editor">	
			<span class="control"></span>
			<span class="control"></span>
			<span class="control"></span>
			<pre class="line-numbers">
				<code class="language-css">
/* 
   Just another pure CSS code editor design.
   Designed based on @roybarberuk's amazing Dribbble shot.
   Dribbble shot: http://dribbble.com/shots/1022371-Landing-Page-Element 

   Lea Verou's Prism syntax highlighter is used along with 
   the line number plugin and the Tomorrow-Theme.
*/

body {
	background: #e16a3f;
}

.code-editor:before,
.code-editor:after,
.code-editor span.control:before,
.code-editor span.after:after {
	box-sizing: border-box;
	-moz-box-sizing: border-box;
	-o-box-sizing: border-box;
	-webkit-box-sizing: border-box;
	content: '';
	position: absolute;
	z-index: 1;
	-webkit-transition: all .5s ease-in-out;
    -moz-transition: wall .5s ease-in-out;
    -o-transition: all .5s ease-in-out;
    transition: all .5s ease-in-out;
}

.code-editor {
	box-sizing: border-box;
	-moz-box-sizing: border-box;
	-o-box-sizing: border-box;
	-webkit-box-sizing: border-box;
	margin: 40px auto 0 auto;
   	width: 750px; 
   	text-align: left;
   	background-color: #473431;
   	border-radius: 0 0 5px 5px;
   	overflow: auto;
   	-webkit-transition: all .5s ease-in-out;
    -moz-transition: wall .5s ease-in-out;
    -o-transition: all .5s ease-in-out;
    transition: all .5s ease-in-out;
}

.code-editor:before {
	content: 'Code Editor';
	font-family: 'Consolas';
	color: #222;
	padding-top: 6px; 
	text-align: center;
	top: 25px;
	width: 750px;
	height: 30px;
	background-color: #fafafa;
	border-radius: 5px 5px 0 0;
	-moz-border-radius: 5px 5px 0 0;
	-o-border-radius: 5px 5px 0 0;
	-webkit-border-radius: 5px 5px 0 0;
}

.code-editor span.control:before {
	content: '';
	top: 34px;
	z-index: 2;
	padding: 6px;
	border-radius: 20px;
	-moz-border-radius: 20px;
	-o-border-radius: 20px;
	-webkit-border-radius: 20px;
}

.code-editor span.control:nth-child(1):before {
	margin-left: 15px;
	background-color: #df6963;
	
}

.code-editor span.control:nth-child(2):before {
	margin-left: 35px;
	background-color: #f5e18a;
	
}

.code-editor span.control:nth-child(3):before {
	margin-left: 55px;
	background-color: #97c38a;
}

/* -- iPad Screen -- */
@media only screen and (min-width: 480px) and (max-width: 768px) {
	.code-editor {
   		width: 500px; 
	}

	.code-editor:before {
		width: 500px;
	}
}

/* -- iPhone Screen -- */
@media only screen and (max-width: 479px) {
	.code-editor {
		width: 300px;
	}	

	.code-editor:before {
		width: 300px;
	}
}</code></pre>
</div>
!

CSS 

              
                body {
	background: #e16a3f;
}

.code-editor:before,
.code-editor:after,
.code-editor span.control:before,
.code-editor span.after:after {
	box-sizing: border-box;
	-moz-box-sizing: border-box;
	-o-box-sizing: border-box;
	-webkit-box-sizing: border-box;
	content: '';
	position: absolute;
	z-index: 1;
	-webkit-transition: all .5s ease-in-out;
    -moz-transition: wall .5s ease-in-out;
    -o-transition: all .5s ease-in-out;
    transition: all .5s ease-in-out;
}

.code-editor {
	box-sizing: border-box;
	-moz-box-sizing: border-box;
	-o-box-sizing: border-box;
	-webkit-box-sizing: border-box;
	margin: 40px auto 0 auto;
   	width: 750px; 
   	text-align: left;
   	background-color: #473431;
   	border-radius: 0 0 5px 5px;
   	overflow: auto;
   	-webkit-transition: all .5s ease-in-out;
    -moz-transition: wall .5s ease-in-out;
    -o-transition: all .5s ease-in-out;
    transition: all .5s ease-in-out;
}

.code-editor:before {
	content: 'Code Editor';
	font-family: 'Consolas';
	color: #222;
	padding-top: 6px; 
	text-align: center;
	top: 25px;
	width: 750px;
	height: 30px;
	background-color: #fafafa;
	border-radius: 5px 5px 0 0;
	-moz-border-radius: 5px 5px 0 0;
	-o-border-radius: 5px 5px 0 0;
	-webkit-border-radius: 5px 5px 0 0;
}

.code-editor span.control:before {
	content: '';
	top: 34px;
	z-index: 2;
	padding: 6px;
	border-radius: 20px;
	-moz-border-radius: 20px;
	-o-border-radius: 20px;
	-webkit-border-radius: 20px;
}

.code-editor span.control:nth-child(1):before {
	margin-left: 15px;
	background-color: #df6963;
	
}

.code-editor span.control:nth-child(2):before {
	margin-left: 35px;
	background-color: #f5e18a;
	
}

.code-editor span.control:nth-child(3):before {
	margin-left: 55px;
	background-color: #97c38a;
}

/* -- iPad Screen -- */
@media only screen and (min-width: 480px) and (max-width: 768px) {
	.code-editor {
   		width: 500px; 
	}

	.code-editor:before {
		width: 500px;
	}
}

/* -- iPhone Screen -- */
@media only screen and (max-width: 479px) {
	.code-editor {
		width: 300px;
	}	

	.code-editor:before {
		width: 300px;
	}
}

/**
 * prism.js tomorrow night eighties for JavaScript, CoffeeScript, CSS and HTML
 * Based on https://github.com/chriskempson/tomorrow-theme
 * @author Rose Pritchard
 */

code[class*="language-"],
pre[class*="language-"] {
  color: #ccc;
  font-family: Consolas, Monaco, 'Andale Mono', monospace;
  direction: ltr;
  text-align: left;
  white-space: pre;
  word-spacing: normal;

  -moz-tab-size: 4;
  -o-tab-size: 4;
  tab-size: 4;

  -webkit-hyphens: none;
  -moz-hyphens: none;
  -ms-hyphens: none;
  hyphens: none;

}

/* Code blocks */
pre[class*="language-"] {
  padding: 1em;
  margin: 0em 0;
  height: 500px;
  overflow: auto;
}

:not(pre) > code[class*="language-"],
pre[class*="language-"] {
  background: #473431;
}

/* Inline code */
:not(pre) > code[class*="language-"] {
  padding: .1em;
  border-radius: .3em;
  -moz-border-radius: .3em;
  -o-border-radius: .3em;
  -webkit-border-radius: .3em;
}

.token.comment,
.token.block-comment,
.token.prolog,
.token.doctype,
.token.cdata {
  color: #999;
}

.token.punctuation {
  color: #ccc;
}


.token.tag,
.token.attr-name,
.token.namespace {
  color: #e2777a;
}

.token.function-name {
  color: #6196cc;
}


.token.boolean,
.token.number,
.token.function {
  color: #f08d49;
}

.token.property,
.token.class-name,
.token.constant,
.token.symbol {
  color: #f8c555;
}

.token.selector,
.token.important,
.token.atrule,
.token.keyword,
.token.builtin {
  color: #cc99cd;
}

.token.string,
.token.attr-value,
.token.regex,
.token.variable {
  color: #7ec699;
}

.token.operator,
.token.entity,
.token.url
{
  color: #67cdcc;
}


.token.important {
  font-weight: bold;
}

.token.entity {
  cursor: help;
}

pre.line-numbers {
	position: relative;
	padding-left: 3.8em;
	counter-reset: linenumber;
	padding-bottom: 1px;
}

pre.line-numbers > code {
	position: relative;
}

.line-numbers .line-numbers-rows {
	position: absolute;
	pointer-events: none;
	top: 0;

	font-size: 100%;
	left: -13em;
	width: 3em; /* works for line-numbers below 1000 lines */
	letter-spacing: -1px;
	background-color: #322422;
	-webkit-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	user-select: none;

}

.line-numbers-rows > span {
	pointer-events: none;
	display: block;
	counter-increment: linenumber;
}

.line-numbers-rows > span:before {
	content: counter(linenumber);
	color: #999;
	display: block;
	padding-right: 0.8em;
	text-align: right;
}
!

JS 

              
                /**
 * Prism: Lightweight, robust, elegant syntax highlighting
 * MIT license https://www.opensource.org/licenses/mit-license.php/
 * @author Lea Verou http://lea.verou.me
 */(function(){var e=/\blang(?:uage)?-(?!\*)(\w+)\b/i,t=self.Prism={util:{type:function(e){return Object.prototype.toString.call(e).match(/\[object (\w+)\]/)[1]},clone:function(e){var n=t.util.type(e);switch(n){case"Object":var r={};for(var i in e)e.hasOwnProperty(i)&&(r[i]=t.util.clone(e[i]));return r;case"Array":return e.slice()}return e}},languages:{extend:function(e,n){var r=t.util.clone(t.languages[e]);for(var i in n)r[i]=n[i];return r},insertBefore:function(e,n,r,i){i=i||t.languages;var s=i[e],o={};for(var u in s)if(s.hasOwnProperty(u)){if(u==n)for(var a in r)r.hasOwnProperty(a)&&(o[a]=r[a]);o[u]=s[u]}return i[e]=o},DFS:function(e,n){for(var r in e){n.call(e,r,e[r]);t.util.type(e)==="Object"&&t.languages.DFS(e[r],n)}}},highlightAll:function(e,n){var r=document.querySelectorAll('code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code');for(var i=0,s;s=r[i++];)t.highlightElement(s,e===!0,n)},highlightElement:function(r,i,s){var o,u,a=r;while(a&&!e.test(a.className))a=a.parentNode;if(a){o=(a.className.match(e)||[,""])[1];u=t.languages[o]}if(!u)return;r.className=r.className.replace(e,"").replace(/\s+/g," ")+" language-"+o;a=r.parentNode;/pre/i.test(a.nodeName)&&(a.className=a.className.replace(e,"").replace(/\s+/g," ")+" language-"+o);var f=r.textContent;if(!f)return;f=f.replace(/&/g,"&amp;").replace(/</g,"&lt;").replace(/\u00a0/g," ");var l={element:r,language:o,grammar:u,code:f};t.hooks.run("before-highlight",l);if(i&&self.Worker){var c=new Worker(t.filename);c.onmessage=function(e){l.highlightedCode=n.stringify(JSON.parse(e.data),o);t.hooks.run("before-insert",l);l.element.innerHTML=l.highlightedCode;s&&s.call(l.element);t.hooks.run("after-highlight",l)};c.postMessage(JSON.stringify({language:l.language,code:l.code}))}else{l.highlightedCode=t.highlight(l.code,l.grammar,l.language);t.hooks.run("before-insert",l);l.element.innerHTML=l.highlightedCode;s&&s.call(r);t.hooks.run("after-highlight",l)}},highlight:function(e,r,i){return n.stringify(t.tokenize(e,r),i)},tokenize:function(e,n,r){var i=t.Token,s=[e],o=n.rest;if(o){for(var u in o)n[u]=o[u];delete n.rest}e:for(var u in n){if(!n.hasOwnProperty(u)||!n[u])continue;var a=n[u],f=a.inside,l=!!a.lookbehind,c=0;a=a.pattern||a;for(var h=0;h<s.length;h++){var p=s[h];if(s.length>e.length)break e;if(p instanceof i)continue;a.lastIndex=0;var d=a.exec(p);if(d){l&&(c=d[1].length);var v=d.index-1+c,d=d[0].slice(c),m=d.length,g=v+m,y=p.slice(0,v+1),b=p.slice(g+1),w=[h,1];y&&w.push(y);var E=new i(u,f?t.tokenize(d,f):d);w.push(E);b&&w.push(b);Array.prototype.splice.apply(s,w)}}}return s},hooks:{all:{},add:function(e,n){var r=t.hooks.all;r[e]=r[e]||[];r[e].push(n)},run:function(e,n){var r=t.hooks.all[e];if(!r||!r.length)return;for(var i=0,s;s=r[i++];)s(n)}}},n=t.Token=function(e,t){this.type=e;this.content=t};n.stringify=function(e,r,i){if(typeof e=="string")return e;if(Object.prototype.toString.call(e)=="[object Array]")return e.map(function(t){return n.stringify(t,r,e)}).join("");var s={type:e.type,content:n.stringify(e.content,r,i),tag:"span",classes:["token",e.type],attributes:{},language:r,parent:i};s.type=="comment"&&(s.attributes.spellcheck="true");t.hooks.run("wrap",s);var o="";for(var u in s.attributes)o+=u+'="'+(s.attributes[u]||"")+'"';return"<"+s.tag+' class="'+s.classes.join(" ")+'" '+o+">"+s.content+"</"+s.tag+">"};if(!self.document){self.addEventListener("message",function(e){var n=JSON.parse(e.data),r=n.language,i=n.code;self.postMessage(JSON.stringify(t.tokenize(i,t.languages[r])));self.close()},!1);return}var r=document.getElementsByTagName("script");r=r[r.length-1];if(r){t.filename=r.src;document.addEventListener&&!r.hasAttribute("data-manual")&&document.addEventListener("DOMContentLoaded",t.highlightAll)}})();;
Prism.languages.markup={comment:/&lt;!--[\w\W]*?-->/g,prolog:/&lt;\?.+?\?>/,doctype:/&lt;!DOCTYPE.+?>/,cdata:/&lt;!\[CDATA\[[\w\W]*?]]>/i,tag:{pattern:/&lt;\/?[\w:-]+\s*(?:\s+[\w:-]+(?:=(?:("|')(\\?[\w\W])*?\1|\w+))?\s*)*\/?>/gi,inside:{tag:{pattern:/^&lt;\/?[\w:-]+/i,inside:{punctuation:/^&lt;\/?/,namespace:/^[\w-]+?:/}},"attr-value":{pattern:/=(?:('|")[\w\W]*?(\1)|[^\s>]+)/gi,inside:{punctuation:/=|>|"/g}},punctuation:/\/?>/g,"attr-name":{pattern:/[\w:-]+/g,inside:{namespace:/^[\w-]+?:/}}}},entity:/&amp;#?[\da-z]{1,8};/gi};Prism.hooks.add("wrap",function(e){e.type==="entity"&&(e.attributes.title=e.content.replace(/&amp;/,"&"))});;
Prism.languages.css={comment:/\/\*[\w\W]*?\*\//g,atrule:{pattern:/@[\w-]+?.*?(;|(?=\s*{))/gi,inside:{punctuation:/[;:]/g}},url:/url\((["']?).*?\1\)/gi,selector:/[^\{\}\s][^\{\};]*(?=\s*\{)/g,property:/(\b|\B)[\w-]+(?=\s*:)/ig,string:/("|')(\\?.)*?\1/g,important:/\B!important\b/gi,ignore:/&(lt|gt|amp);/gi,punctuation:/[\{\};:]/g};Prism.languages.markup&&Prism.languages.insertBefore("markup","tag",{style:{pattern:/(&lt;|<)style[\w\W]*?(>|&gt;)[\w\W]*?(&lt;|<)\/style(>|&gt;)/ig,inside:{tag:{pattern:/(&lt;|<)style[\w\W]*?(>|&gt;)|(&lt;|<)\/style(>|&gt;)/ig,inside:Prism.languages.markup.tag.inside},rest:Prism.languages.css}}});;
Prism.languages.clike={comment:{pattern:/(^|[^\\])(\/\*[\w\W]*?\*\/|(^|[^:])\/\/.*?(\r?\n|$))/g,lookbehind:!0},string:/("|')(\\?.)*?\1/g,"class-name":{pattern:/((?:(?:class|interface|extends|implements|trait|instanceof|new)\s+)|(?:catch\s+\())[a-z0-9_\.\\]+/ig,lookbehind:!0,inside:{punctuation:/(\.|\\)/}},keyword:/\b(if|else|while|do|for|return|in|instanceof|function|new|try|throw|catch|finally|null|break|continue)\b/g,"boolean":/\b(true|false)\b/g,"function":{pattern:/[a-z0-9_]+\(/ig,inside:{punctuation:/\(/}}, number:/\b-?(0x[\dA-Fa-f]+|\d*\.?\d+([Ee]-?\d+)?)\b/g,operator:/[-+]{1,2}|!|&lt;=?|>=?|={1,3}|(&amp;){1,2}|\|?\||\?|\*|\/|\~|\^|\%/g,ignore:/&(lt|gt|amp);/gi,punctuation:/[{}[\];(),.:]/g};
;
Prism.languages.javascript=Prism.languages.extend("clike",{keyword:/\b(var|let|if|else|while|do|for|return|in|instanceof|function|new|with|typeof|try|throw|catch|finally|null|break|continue)\b/g,number:/\b-?(0x[\dA-Fa-f]+|\d*\.?\d+([Ee]-?\d+)?|NaN|-?Infinity)\b/g});Prism.languages.insertBefore("javascript","keyword",{regex:{pattern:/(^|[^/])\/(?!\/)(\[.+?]|\\.|[^/\r\n])+\/[gim]{0,3}(?=\s*($|[\r\n,.;})]))/g,lookbehind:!0}});Prism.languages.markup&&Prism.languages.insertBefore("markup","tag",{script:{pattern:/(&lt;|<)script[\w\W]*?(>|&gt;)[\w\W]*?(&lt;|<)\/script(>|&gt;)/ig,inside:{tag:{pattern:/(&lt;|<)script[\w\W]*?(>|&gt;)|(&lt;|<)\/script(>|&gt;)/ig,inside:Prism.languages.markup.tag.inside},rest:Prism.languages.javascript}}});
;
Prism.hooks.add("after-highlight",function(e){var t=e.element.parentNode;if(!t||!/pre/i.test(t.nodeName)||t.className.indexOf("line-numbers")===-1){return}var n=1+e.code.split("\n").length;var r;lines=new Array(n);lines=lines.join("<span></span>");r=document.createElement("span");r.className="line-numbers-rows";r.innerHTML=lines;if(t.hasAttribute("data-start")){t.style.counterReset="linenumber "+(parseInt(t.getAttribute("data-start"),10)-1)}e.element.appendChild(r)})
;
!
999px

Console