Nieve en el blog que se acumula al final de la página

La temporada navideña ya es oficial, y al menos los que estamos en el hemisferio norte relacionamos la nieve con la Navidad, así que es hora de abrigarnos porque haremos que caiga nieve en el blog.

En esta ocasión usaremos un script de Schillmania que hará que caigan unos finos copos de nieve en el blog y que se irán acumulando al final de la página. Además, la tormenta de nieve se mueve en dirección contraria al cursor, por lo que si movemos el cursor a la derecha entonces la nieve caerá desde la izquierda y viceversa.

Puedes ver un ejemplo en este blog de pruebas.

Para no complicarnos descargando y subiendo archivos, pegaremos el script directo en un gadget, así podrás quitar la nieve del blog cuando quieras con sólo eliminar el gadget.

Si usas la interfaz antigua entra en Diseño | Elementos de la página | Añadir un gadget | HTML/Javascript.

Si usas la nueva interfaz entra en Diseño | Añadir un gadget | HTML/Javascript.

Ahí dentro del gadget pega el siguiente código:

<script type="text/javascript">
//<![CDATA[
// Nieve en el blog
/** @license
DHTML Snowstorm! JavaScript-based Snow for web pages
--------------------------------------------------------
Version 1.42.20111120 (Previous rev: 1.41.20101113)
Copyright (c) 2007, Scott Schiller. All rights reserved.
Code provided under the BSD License:
http://schillmania.com/projects/snowstorm/license.txt
*/
var snowStorm=function(e,d){function g(a,d){isNaN(d)&&(d=0);return Math.random()*a+d}function o(){e.setTimeout(function(){a.start(true)},20);a.events.remove(i?d:e,"mousemove",o)}function r(){if(!a.excludeMobile||!s)a.freezeOnBlur?a.events.add(i?d:e,"mousemove",o):o();a.events.remove(e,"load",r)}this.flakesMax=128;this.flakesMaxActive=64;this.animationInterval=40;this.excludeMobile=true;this.flakeBottom=null;this.followMouse=true;this.snowColor="#ffffff";this.snowCharacter="&bull;";this.snowStick=true;
this.targetElement=null;this.useMeltEffect=true;this.usePositionFixed=this.useTwinkleEffect=false;this.freezeOnBlur=true;this.flakeRightOffset=this.flakeLeftOffset=0;this.flakeHeight=this.flakeWidth=8;this.vMaxX=5;this.vMaxY=4;this.zIndex=0;var a=this,y=this,i=navigator.userAgent.match(/msie/i),z=navigator.userAgent.match(/msie 6/i),A=navigator.appVersion.match(/windows 98/i),s=navigator.userAgent.match(/mobile/i),B=i&&d.compatMode==="BackCompat",t=s||B||z,h=null,k=null,j=null,m=null,u=null,v=null,
p=1,n=false,q;a:{try{d.createElement("div").style.opacity="0.5"}catch(C){q=false;break a}q=true}var w=false,x=d.createDocumentFragment();this.timers=[];this.flakes=[];this.active=this.disabled=false;this.meltFrameCount=20;this.meltFrames=[];this.events=function(){function a(b){var b=f.call(b),c=b.length;l?(b[1]="on"+b[1],c>3&&b.pop()):c===3&&b.push(false);return b}function d(a,c){var e=a.shift(),f=[b[c]];if(l)e[f](a[0],a[1]);else e[f].apply(e,a)}var l=!e.addEventListener&&e.attachEvent,f=Array.prototype.slice,
b={add:l?"attachEvent":"addEventListener",remove:l?"detachEvent":"removeEventListener"};return{add:function(){d(a(arguments),"add")},remove:function(){d(a(arguments),"remove")}}}();this.randomizeWind=function(){var c;c=g(a.vMaxX,0.2);u=parseInt(g(2),10)===1?c*-1:c;v=g(a.vMaxY,0.2);if(this.flakes)for(c=0;c<this.flakes.length;c++)this.flakes[c].active&&this.flakes[c].setVelocities()};this.scrollHandler=function(){var c;m=a.flakeBottom?0:parseInt(e.scrollY||d.documentElement.scrollTop||d.body.scrollTop,
10);isNaN(m)&&(m=0);if(!n&&!a.flakeBottom&&a.flakes)for(c=a.flakes.length;c--;)a.flakes[c].active===0&&a.flakes[c].stick()};this.resizeHandler=function(){e.innerWidth||e.innerHeight?(h=e.innerWidth-(!i?16:16)-a.flakeRightOffset,j=a.flakeBottom?a.flakeBottom:e.innerHeight):(h=(d.documentElement.clientWidth||d.body.clientWidth||d.body.scrollWidth)-(!i?8:0)-a.flakeRightOffset,j=a.flakeBottom?a.flakeBottom:d.documentElement.clientHeight||d.body.clientHeight||d.body.scrollHeight);k=parseInt(h/2,10)};this.resizeHandlerAlt=
function(){h=a.targetElement.offsetLeft+a.targetElement.offsetWidth-a.flakeRightOffset;j=a.flakeBottom?a.flakeBottom:a.targetElement.offsetTop+a.targetElement.offsetHeight;k=parseInt(h/2,10)};this.freeze=function(){var c;if(a.disabled)return false;else a.disabled=1;for(c=a.timers.length;c--;)clearInterval(a.timers[c])};this.resume=function(){if(a.disabled)a.disabled=0;else return false;a.timerInit()};this.toggleSnow=function(){a.flakes.length?(a.active=!a.active,a.active?(a.show(),a.resume()):(a.stop(),
a.freeze())):a.start()};this.stop=function(){var c;this.freeze();for(c=this.flakes.length;c--;)this.flakes[c].o.style.display="none";a.events.remove(e,"scroll",a.scrollHandler);a.events.remove(e,"resize",a.resizeHandler);a.freezeOnBlur&&(i?(a.events.remove(d,"focusout",a.freeze),a.events.remove(d,"focusin",a.resume)):(a.events.remove(e,"blur",a.freeze),a.events.remove(e,"focus",a.resume)))};this.show=function(){var a;for(a=this.flakes.length;a--;)this.flakes[a].o.style.display="block"};this.SnowFlake=
function(a,e,l,f){var b=this;this.type=e;this.x=l||parseInt(g(h-20),10);this.y=!isNaN(f)?f:-g(j)-12;this.vY=this.vX=null;this.vAmpTypes=[1,1.2,1.4,1.6,1.8];this.vAmp=this.vAmpTypes[this.type];this.melting=false;this.meltFrameCount=a.meltFrameCount;this.meltFrames=a.meltFrames;this.twinkleFrame=this.meltFrame=0;this.active=1;this.fontSize=10+this.type/5*10;this.o=d.createElement("div");this.o.innerHTML=a.snowCharacter;this.o.style.color=a.snowColor;this.o.style.position=n?"fixed":"absolute";this.o.style.width=
a.flakeWidth+"px";this.o.style.height=a.flakeHeight+"px";this.o.style.fontFamily="arial,verdana";this.o.style.overflow="hidden";this.o.style.fontWeight="normal";this.o.style.zIndex=a.zIndex;x.appendChild(this.o);this.refresh=function(){if(isNaN(b.x)||isNaN(b.y))return false;b.o.style.left=b.x+"px";b.o.style.top=b.y+"px"};this.stick=function(){t||a.targetElement!==d.documentElement&&a.targetElement!==d.body?b.o.style.top=j+m-a.flakeHeight+"px":a.flakeBottom?b.o.style.top=a.flakeBottom+"px":(b.o.style.display=
"none",b.o.style.top="auto",b.o.style.bottom="0px",b.o.style.position="fixed",b.o.style.display="block")};this.vCheck=function(){if(b.vX>=0&&b.vX<0.2)b.vX=0.2;else if(b.vX<0&&b.vX>-0.2)b.vX=-0.2;if(b.vY>=0&&b.vY<0.2)b.vY=0.2};this.move=function(){var d=b.vX*p;b.x+=d;b.y+=b.vY*b.vAmp;if(b.x>=h||h-b.x<a.flakeWidth)b.x=0;else if(d<0&&b.x-a.flakeLeftOffset<-a.flakeWidth)b.x=h-a.flakeWidth-1;b.refresh();if(j+m-b.y<a.flakeHeight)b.active=0,a.snowStick?b.stick():b.recycle();else{if(a.useMeltEffect&&b.active&&
b.type<3&&!b.melting&&Math.random()>0.998)b.melting=true,b.melt();if(a.useTwinkleEffect)if(b.twinkleFrame)b.twinkleFrame--,b.o.style.visibility=b.twinkleFrame&&b.twinkleFrame%2===0?"hidden":"visible";else if(Math.random()>0.9)b.twinkleFrame=parseInt(Math.random()*20,10)}};this.animate=function(){b.move()};this.setVelocities=function(){b.vX=u+g(a.vMaxX*0.12,0.1);b.vY=v+g(a.vMaxY*0.12,0.1)};this.setOpacity=function(a,b){if(!q)return false;a.style.opacity=b};this.melt=function(){!a.useMeltEffect||!b.melting?
b.recycle():b.meltFrame<b.meltFrameCount?(b.meltFrame++,b.setOpacity(b.o,b.meltFrames[b.meltFrame]),b.o.style.fontSize=b.fontSize-b.fontSize*(b.meltFrame/b.meltFrameCount)+"px",b.o.style.lineHeight=a.flakeHeight+2+a.flakeHeight*0.75*(b.meltFrame/b.meltFrameCount)+"px"):b.recycle()};this.recycle=function(){b.o.style.display="none";b.o.style.position=n?"fixed":"absolute";b.o.style.bottom="auto";b.setVelocities();b.vCheck();b.meltFrame=0;b.melting=false;b.setOpacity(b.o,1);b.o.style.padding="0px";b.o.style.margin=
"0px";b.o.style.fontSize=b.fontSize+"px";b.o.style.lineHeight=a.flakeHeight+2+"px";b.o.style.textAlign="center";b.o.style.verticalAlign="baseline";b.x=parseInt(g(h-a.flakeWidth-20),10);b.y=parseInt(g(j)*-1,10)-a.flakeHeight;b.refresh();b.o.style.display="block";b.active=1};this.recycle();this.refresh()};this.snow=function(){for(var c=0,d=0,e=0,f=null,f=a.flakes.length;f--;)a.flakes[f].active===1?(a.flakes[f].move(),c++):a.flakes[f].active===0?d++:e++,a.flakes[f].melting&&a.flakes[f].melt();if(c<a.flakesMaxActive&&
(f=a.flakes[parseInt(g(a.flakes.length),10)],f.active===0))f.melting=true};this.mouseMove=function(c){if(!a.followMouse)return true;c=parseInt(c.clientX,10);c<k?p=-2+c/k*2:(c-=k,p=c/k*2)};this.createSnow=function(c,d){var e;for(e=0;e<c;e++)if(a.flakes[a.flakes.length]=new a.SnowFlake(a,parseInt(g(6),10)),d||e>a.flakesMaxActive)a.flakes[a.flakes.length-1].active=-1;y.targetElement.appendChild(x)};this.timerInit=function(){a.timers=!A?[setInterval(a.snow,a.animationInterval)]:[setInterval(a.snow,a.animationInterval*
3),setInterval(a.snow,a.animationInterval)]};this.init=function(){var c;for(c=0;c<a.meltFrameCount;c++)a.meltFrames.push(1-c/a.meltFrameCount);a.randomizeWind();a.createSnow(a.flakesMax);a.events.add(e,"resize",a.resizeHandler);a.events.add(e,"scroll",a.scrollHandler);a.freezeOnBlur&&(i?(a.events.add(d,"focusout",a.freeze),a.events.add(d,"focusin",a.resume)):(a.events.add(e,"blur",a.freeze),a.events.add(e,"focus",a.resume)));a.resizeHandler();a.scrollHandler();a.followMouse&&a.events.add(i?d:e,"mousemove",
a.mouseMove);a.animationInterval=Math.max(20,a.animationInterval);a.timerInit()};this.start=function(c){if(w){if(c)return true}else w=true;if(typeof a.targetElement==="string"&&(c=a.targetElement,a.targetElement=d.getElementById(c),!a.targetElement))throw Error('Snowstorm: Unable to get targetElement "'+c+'"');if(!a.targetElement)a.targetElement=!i?d.documentElement?d.documentElement:d.body:d.body;if(a.targetElement!==d.documentElement&&a.targetElement!==d.body)a.resizeHandler=a.resizeHandlerAlt;
a.resizeHandler();a.usePositionFixed=a.usePositionFixed&&!t;n=a.usePositionFixed;if(h&&j&&!a.disabled)a.init(),a.active=true};a.events.add(e,"load",r,false);return this}(window,document);
//]]>
</script>

Guarda los cambios y a aguantarse el frío virtual.

El número 40 es la velocidad en la que cae la nieve, con un valor más bajo caerá más rápida y con uno más alto caerá más despacio.

En color rojo está el código del color de la nieve, en este caso es blanca, pero puedes cambiarlo por otro en caso que tu blog sea de un color claro, sino pues no se verá.

Cuando acabe la temporada navideña sólo elimina el gadget donde pusiste el código y se habrá ido la nieve.