Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URLs added here will be added as <link>s in order, and before the CSS in the editor. You can use the CSS from another Pen by using its URL and the proper URL extension.

+ add another resource

JavaScript

Babel includes JSX processing.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

Behavior

Auto Save

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.

HTML

              
                <!-- Legacy code used as example code on http://css-plus.com/2012/03/css-animation-how-it-works-from-transitions-to-animations -->
<div class="animation">
    <div class="support">Yay! Your browser does support CSS animations!</div>
    <div class="no-support">Boo! Your browser does not support CSS animations!</div>
</div>

              
            
!

CSS

              
                .animation div { display: none; } /* Hide both messages */

/* Does not support */
.no-cssanimations .animation .no-support { color: red; display: block; }

/* Supports */
.cssanimations .animation .support {
    -webkit-animation: animation-support 2s ease-in infinite alternate;
    -moz-animation: animation-support 2s ease-in infinite alternate;
    -ms-animation: animation-support 2s ease-in infinite alternate;
    -o-animation: animation-support 2s ease-in infinite alternate;
    animation: animation-support 2s ease-in infinite alternate;
    color: green;
    display: block;
    text-shadow: 1px 1px 0 rgba(0,0,0,0.3);
}
@-webkit-keyframes animation-support {
    from { margin-left: 0; }
    to { margin-left: 200px; }
}
@-moz-keyframes animation-support {
    from { margin-left: 0; }
    to { margin-left: 200px; }
}
@-ms-keyframes animation-support {
    from { margin-left: 0; }
    to { margin-left: 200px; }
}
@-o-keyframes animation-support {
    from { margin-left: 0; }
    to { margin-left: 200px; }
}
@keyframes animation-support {
    from { margin-left: 0; }
    to { margin-left: 200px; }
}
              
            
!

JS

              
                // Adding modernizr to the JS to so as not to rely on external dependencie for the codepen

/* Modernizr 2.5.3 (Custom Build) | MIT & BSD
 * Build: http://www.modernizr.com/download/#-fontface-backgroundsize-borderimage-borderradius-boxshadow-flexbox-hsla-multiplebgs-opacity-rgba-textshadow-cssanimations-csscolumns-generatedcontent-cssgradients-cssreflections-csstransforms-csstransforms3d-csstransitions-applicationcache-canvas-canvastext-draganddrop-hashchange-history-audio-video-indexeddb-input-inputtypes-localstorage-postmessage-sessionstorage-websockets-websqldatabase-webworkers-geolocation-inlinesvg-smil-svg-svgclippaths-touch-webgl-shiv-cssclasses-teststyles-testprop-testallprops-hasevent-prefixes-domprefixes-load
 */
;window.Modernizr=function(a,b,c){function C(a){j.cssText=a}function D(a,b){return C(n.join(a+";")+(b||""))}function E(a,b){return typeof a===b}function F(a,b){return!!~(""+a).indexOf(b)}function G(a,b){for(var d in a)if(j[a[d]]!==c)return b=="pfx"?a[d]:!0;return!1}function H(a,b,d){for(var e in a){var f=b[a[e]];if(f!==c)return d===!1?a[e]:E(f,"function")?f.bind(d||b):f}return!1}function I(a,b,c){var d=a.charAt(0).toUpperCase()+a.substr(1),e=(a+" "+p.join(d+" ")+d).split(" ");return E(b,"string")||E(b,"undefined")?G(e,b):(e=(a+" "+q.join(d+" ")+d).split(" "),H(e,b,c))}function K(){e.input=function(c){for(var d=0,e=c.length;d<e;d++)u[c[d]]=c[d]in k;return u.list&&(u.list=!!b.createElement("datalist")&&!!a.HTMLDataListElement),u}("autocomplete autofocus list placeholder max min multiple pattern required step".split(" ")),e.inputtypes=function(a){for(var d=0,e,f,h,i=a.length;d<i;d++)k.setAttribute("type",f=a[d]),e=k.type!=="text",e&&(k.value=l,k.style.cssText="position:absolute;visibility:hidden;",/^range$/.test(f)&&k.style.WebkitAppearance!==c?(g.appendChild(k),h=b.defaultView,e=h.getComputedStyle&&h.getComputedStyle(k,null).WebkitAppearance!=="textfield"&&k.offsetHeight!==0,g.removeChild(k)):/^(search|tel)$/.test(f)||(/^(url|email)$/.test(f)?e=k.checkValidity&&k.checkValidity()===!1:/^color$/.test(f)?(g.appendChild(k),g.offsetWidth,e=k.value!=l,g.removeChild(k)):e=k.value!=l)),t[a[d]]=!!e;return t}("search tel url email datetime date month week time datetime-local number range color".split(" "))}var d="2.5.3",e={},f=!0,g=b.documentElement,h="modernizr",i=b.createElement(h),j=i.style,k=b.createElement("input"),l=":)",m={}.toString,n=" -webkit- -moz- -o- -ms- ".split(" "),o="Webkit Moz O ms",p=o.split(" "),q=o.toLowerCase().split(" "),r={svg:"http://www.w3.org/2000/svg"},s={},t={},u={},v=[],w=v.slice,x,y=function(a,c,d,e){var f,i,j,k=b.createElement("div"),l=b.body,m=l?l:b.createElement("body");if(parseInt(d,10))while(d--)j=b.createElement("div"),j.id=e?e[d]:h+(d+1),k.appendChild(j);return f=["&#173;","<style>",a,"</style>"].join(""),k.id=h,m.innerHTML+=f,m.appendChild(k),l||(m.style.background="",g.appendChild(m)),i=c(k,a),l?k.parentNode.removeChild(k):m.parentNode.removeChild(m),!!i},z=function(){function d(d,e){e=e||b.createElement(a[d]||"div"),d="on"+d;var f=d in e;return f||(e.setAttribute||(e=b.createElement("div")),e.setAttribute&&e.removeAttribute&&(e.setAttribute(d,""),f=E(e[d],"function"),E(e[d],"undefined")||(e[d]=c),e.removeAttribute(d))),e=null,f}var a={select:"input",change:"input",submit:"form",reset:"form",error:"img",load:"img",abort:"img"};return d}(),A={}.hasOwnProperty,B;!E(A,"undefined")&&!E(A.call,"undefined")?B=function(a,b){return A.call(a,b)}:B=function(a,b){return b in a&&E(a.constructor.prototype[b],"undefined")},Function.prototype.bind||(Function.prototype.bind=function(b){var c=this;if(typeof c!="function")throw new TypeError;var d=w.call(arguments,1),e=function(){if(this instanceof e){var a=function(){};a.prototype=c.prototype;var f=new a,g=c.apply(f,d.concat(w.call(arguments)));return Object(g)===g?g:f}return c.apply(b,d.concat(w.call(arguments)))};return e});var J=function(c,d){var f=c.join(""),g=d.length;y(f,function(c,d){var f=b.styleSheets[b.styleSheets.length-1],h=f?f.cssRules&&f.cssRules[0]?f.cssRules[0].cssText:f.cssText||"":"",i=c.childNodes,j={};while(g--)j[i[g].id]=i[g];e.touch="ontouchstart"in a||a.DocumentTouch&&b instanceof DocumentTouch||(j.touch&&j.touch.offsetTop)===9,e.csstransforms3d=(j.csstransforms3d&&j.csstransforms3d.offsetLeft)===9&&j.csstransforms3d.offsetHeight===3,e.generatedcontent=(j.generatedcontent&&j.generatedcontent.offsetHeight)>=1,e.fontface=/src/i.test(h)&&h.indexOf(d.split(" ")[0])===0},g,d)}(['@font-face {font-family:"font";src:url("https://")}',["@media (",n.join("touch-enabled),("),h,")","{#touch{top:9px;position:absolute}}"].join(""),["@media (",n.join("transform-3d),("),h,")","{#csstransforms3d{left:9px;position:absolute;height:3px;}}"].join(""),['#generatedcontent:after{content:"',l,'";visibility:hidden}'].join("")],["fontface","touch","csstransforms3d","generatedcontent"]);s.flexbox=function(){return I("flexOrder")},s.canvas=function(){var a=b.createElement("canvas");return!!a.getContext&&!!a.getContext("2d")},s.canvastext=function(){return!!e.canvas&&!!E(b.createElement("canvas").getContext("2d").fillText,"function")},s.webgl=function(){try{var d=b.createElement("canvas"),e;e=!(!a.WebGLRenderingContext||!d.getContext("experimental-webgl")&&!d.getContext("webgl")),d=c}catch(f){e=!1}return e},s.touch=function(){return e.touch},s.geolocation=function(){return!!navigator.geolocation},s.postmessage=function(){return!!a.postMessage},s.websqldatabase=function(){return!!a.openDatabase},s.indexedDB=function(){return!!I("indexedDB",a)},s.hashchange=function(){return z("hashchange",a)&&(b.documentMode===c||b.documentMode>7)},s.history=function(){return!!a.history&&!!history.pushState},s.draganddrop=function(){var a=b.createElement("div");return"draggable"in a||"ondragstart"in a&&"ondrop"in a},s.websockets=function(){for(var b=-1,c=p.length;++b<c;)if(a[p[b]+"WebSocket"])return!0;return"WebSocket"in a},s.rgba=function(){return C("background-color:rgba(150,255,150,.5)"),F(j.backgroundColor,"rgba")},s.hsla=function(){return C("background-color:hsla(120,40%,100%,.5)"),F(j.backgroundColor,"rgba")||F(j.backgroundColor,"hsla")},s.multiplebgs=function(){return C("background:url(https://),url(https://),red url(https://)"),/(url\s*\(.*?){3}/.test(j.background)},s.backgroundsize=function(){return I("backgroundSize")},s.borderimage=function(){return I("borderImage")},s.borderradius=function(){return I("borderRadius")},s.boxshadow=function(){return I("boxShadow")},s.textshadow=function(){return b.createElement("div").style.textShadow===""},s.opacity=function(){return D("opacity:.55"),/^0.55$/.test(j.opacity)},s.cssanimations=function(){return I("animationName")},s.csscolumns=function(){return I("columnCount")},s.cssgradients=function(){var a="background-image:",b="gradient(linear,left top,right bottom,from(#9f9),to(white));",c="linear-gradient(left top,#9f9, white);";return C((a+"-webkit- ".split(" ").join(b+a)+n.join(c+a)).slice(0,-a.length)),F(j.backgroundImage,"gradient")},s.cssreflections=function(){return I("boxReflect")},s.csstransforms=function(){return!!I("transform")},s.csstransforms3d=function(){var a=!!I("perspective");return a&&"webkitPerspective"in g.style&&(a=e.csstransforms3d),a},s.csstransitions=function(){return I("transition")},s.fontface=function(){return e.fontface},s.generatedcontent=function(){return e.generatedcontent},s.video=function(){var a=b.createElement("video"),c=!1;try{if(c=!!a.canPlayType)c=new Boolean(c),c.ogg=a.canPlayType('video/ogg; codecs="theora"').replace(/^no$/,""),c.h264=a.canPlayType('video/mp4; codecs="avc1.42E01E"').replace(/^no$/,""),c.webm=a.canPlayType('video/webm; codecs="vp8, vorbis"').replace(/^no$/,"")}catch(d){}return c},s.audio=function(){var a=b.createElement("audio"),c=!1;try{if(c=!!a.canPlayType)c=new Boolean(c),c.ogg=a.canPlayType('audio/ogg; codecs="vorbis"').replace(/^no$/,""),c.mp3=a.canPlayType("audio/mpeg;").replace(/^no$/,""),c.wav=a.canPlayType('audio/wav; codecs="1"').replace(/^no$/,""),c.m4a=(a.canPlayType("audio/x-m4a;")||a.canPlayType("audio/aac;")).replace(/^no$/,"")}catch(d){}return c},s.localstorage=function(){try{return localStorage.setItem(h,h),localStorage.removeItem(h),!0}catch(a){return!1}},s.sessionstorage=function(){try{return sessionStorage.setItem(h,h),sessionStorage.removeItem(h),!0}catch(a){return!1}},s.webworkers=function(){return!!a.Worker},s.applicationcache=function(){return!!a.applicationCache},s.svg=function(){return!!b.createElementNS&&!!b.createElementNS(r.svg,"svg").createSVGRect},s.inlinesvg=function(){var a=b.createElement("div");return a.innerHTML="<svg/>",(a.firstChild&&a.firstChild.namespaceURI)==r.svg},s.smil=function(){return!!b.createElementNS&&/SVGAnimate/.test(m.call(b.createElementNS(r.svg,"animate")))},s.svgclippaths=function(){return!!b.createElementNS&&/SVGClipPath/.test(m.call(b.createElementNS(r.svg,"clipPath")))};for(var L in s)B(s,L)&&(x=L.toLowerCase(),e[x]=s[L](),v.push((e[x]?"":"no-")+x));return e.input||K(),C(""),i=k=null,function(a,b){function g(a,b){var c=a.createElement("p"),d=a.getElementsByTagName("head")[0]||a.documentElement;return c.innerHTML="x<style>"+b+"</style>",d.insertBefore(c.lastChild,d.firstChild)}function h(){var a=k.elements;return typeof a=="string"?a.split(" "):a}function i(a){var b={},c=a.createElement,e=a.createDocumentFragment,f=e();a.createElement=function(a){var e=(b[a]||(b[a]=c(a))).cloneNode();return k.shivMethods&&e.canHaveChildren&&!d.test(a)?f.appendChild(e):e},a.createDocumentFragment=Function("h,f","return function(){var n=f.cloneNode(),c=n.createElement;h.shivMethods&&("+h().join().replace(/\w+/g,function(a){return b[a]=c(a),f.createElement(a),'c("'+a+'")'})+");return n}")(k,f)}function j(a){var b;return a.documentShived?a:(k.shivCSS&&!e&&(b=!!g(a,"article,aside,details,figcaption,figure,footer,header,hgroup,nav,section{display:block}audio{display:none}canvas,video{display:inline-block;*display:inline;*zoom:1}[hidden]{display:none}audio[controls]{display:inline-block;*display:inline;*zoom:1}mark{background:#FF0;color:#000}")),f||(b=!i(a)),b&&(a.documentShived=b),a)}var c=a.html5||{},d=/^<|^(?:button|form|map|select|textarea)$/i,e,f;(function(){var a=b.createElement("a");a.innerHTML="<xyz></xyz>",e="hidden"in a,f=a.childNodes.length==1||function(){try{b.createElement("a")}catch(a){return!0}var c=b.createDocumentFragment();return typeof c.cloneNode=="undefined"||typeof c.createDocumentFragment=="undefined"||typeof c.createElement=="undefined"}()})();var k={elements:c.elements||"abbr article aside audio bdi canvas data datalist details figcaption figure footer header hgroup mark meter nav output progress section summary time video",shivCSS:c.shivCSS!==!1,shivMethods:c.shivMethods!==!1,type:"default",shivDocument:j};a.html5=k,j(b)}(this,b),e._version=d,e._prefixes=n,e._domPrefixes=q,e._cssomPrefixes=p,e.hasEvent=z,e.testProp=function(a){return G([a])},e.testAllProps=I,e.testStyles=y,g.className=g.className.replace(/(^|\s)no-js(\s|$)/,"$1$2")+(f?" js "+v.join(" "):""),e}(this,this.document),function(a,b,c){function d(a){return o.call(a)=="[object Function]"}function e(a){return typeof a=="string"}function f(){}function g(a){return!a||a=="loaded"||a=="complete"||a=="uninitialized"}function h(){var a=p.shift();q=1,a?a.t?m(function(){(a.t=="c"?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){a!="img"&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l={},o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};y[c]===1&&(r=1,y[c]=[],l=b.createElement(a)),a=="object"?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),a!="img"&&(r||y[c]===2?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i(b=="c"?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),p.length==1&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&o.call(a.opera)=="[object Opera]",l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return o.call(a)=="[object Array]"},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,i){var j=b(a),l=j.autoCallback;j.url.split(".").pop().split("?").shift(),j.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]||h),j.instead?j.instead(a,e,f,g,i):(y[j.url]?j.noexec=!0:y[j.url]=1,f.load(j.url,j.forceCSS||!j.forceJS&&"css"==j.url.split(".").pop().split("?").shift()?"c":c,j.noexec,j.attrs,j.timeout),(d(e)||d(l))&&f.load(function(){k(),e&&e(j.origUrl,i,g),l&&l(j.origUrl,i,g),y[j.url]=2})))}function i(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var j,l,m=this.yepnope.loader;if(e(a))g(a,0,m,0);else if(w(a))for(j=0;j<a.length;j++)l=a[j],e(l)?g(l,0,m,0):w(l)?B(l):Object(l)===l&&i(l,m);else Object(a)===a&&i(a,m)},B.addPrefix=function(a,b){z[a]=b},B.addFilter=function(a){x.push(a)},B.errorTimeout=1e4,b.readyState==null&&b.addEventListener&&(b.readyState="loading",b.addEventListener("DOMContentLoaded",A=function(){b.removeEventListener("DOMContentLoaded",A,0),b.readyState="complete"},0)),a.yepnope=k(),a.yepnope.executeStack=h,a.yepnope.injectJs=function(a,c,d,e,i,j){var k=b.createElement("script"),l,o,e=e||B.errorTimeout;k.src=a;for(o in d)k.setAttribute(o,d[o]);c=j?h:c||f,k.onreadystatechange=k.onload=function(){!l&&g(k.readyState)&&(l=1,c(),k.onload=k.onreadystatechange=null)},m(function(){l||(l=1,c(1))},e),i?k.onload():n.parentNode.insertBefore(k,n)},a.yepnope.injectCss=function(a,c,d,e,g,i){var e=b.createElement("link"),j,c=i?h:c||f;e.href=a,e.rel="stylesheet",e.type="text/css";for(j in d)e.setAttribute(j,d[j]);g||(n.parentNode.insertBefore(e,n),m(c,0))}}(this,document),Modernizr.load=function(){yepnope.apply(window,[].slice.call(arguments,0))};
              
            
!
999px

Console