极光效果：js+jquery+canvas，使用请自行引用jquery插件

html代码：

<div class="background">
	<canvas id="startrack" width="1499" height="1312"></canvas>
	<div class="cover">
	</div>
</div>

js特效代码：

window.requestAnimFrame=window.requestAnimationFrame||window.webkitRequestAnimationFrame||window.mozRequestAnimationFrame||window.oRequestAnimationFrame||window.msRequestAnimationFrame||function(t){window.setTimeout(t,1e3/60)},window.onresize=function(){c.width=cw=c.offsetWidth,c.height=ch=c.offsetHeight,ctx.fillStyle="rgba(21,21,21,1)",ctx.fillRect(0,0,cw,ch)};var cf=document.createElement("canvas"),c=document.getElementById("startrack");c.width=cf.width=cw=c.offsetWidth,c.height=cf.height=ch=c.offsetHeight;var longside=Math.max(cw,ch);cf.width=2.6*longside,cf.height=2.6*longside;var ctx=c.getContext("2d"),cftx=cf.getContext("2d"),centerX=cw,centerY=0,stars=[],drawTimes=0;function rand(t,a){var e=a-t,n=Math.random();return t+Math.round(n*e)}function createStar(){stars.push({x:rand(-cf.width,cf.width),y:rand(-cf.height,cf.height),size:1,color:randomColor()})}function randomColor(){return"rgba("+rand(120,255)+","+rand(120,255)+","+rand(120,255)+","+rand(30,100)/100+")"}function drawStar(){for(var t=stars.length;t--;){var a=stars[t];cftx.beginPath(),cftx.arc(a.x,a.y,a.size,0,2*Math.PI,!0),cftx.fillStyle=a.color,cftx.closePath(),cftx.fill()}}function drawfromCache(){ctx.drawImage(cf,-cf.width/2,-cf.height/2)}function loop(){drawfromCache(),++drawTimes>150&&drawTimes%8==0&&(ctx.fillStyle="rgba(0,0,0,.04)",ctx.fillRect(-3*longside,-3*longside,6*longside,6*longside)),rotateCanvas(.025)}function rotateCanvas(t){ctx.rotate(t*Math.PI/180)}ctx.fillStyle="rgba(21,21,21,1)",ctx.fillRect(0,0,cw,ch),ctx.lineCap="round";for(var count=2e4;count--;)createStar();drawStar();var x=centerX,y=centerY;function fireAnimate(){requestAnimFrame(fireAnimate),loop()}function changeStar(){loop=function(){drawfromCache(),++drawTimes>150&&drawTimes%8==0&&(ctx.fillStyle="rgba(0,0,0,.04)",ctx.fillRect(-3*longside,-3*longside,6*longside,6*longside)),rotateCanvas(random(1,100))}}function getMsg(){var t=["七娃：www.51qux.com"],a=random(0,t.length-1);$("#slogan").html(t[a])}function random(t,a){var e=a-t,n=Math.random();return t+Math.round(n*e)}ctx.translate(x,y),fireAnimate(),$(function(){getMsg()}),window.onscroll=function(){$(window).scrollTop()>.6*$(window).height()?$(".background").addClass("fixed"):$(".background").removeClass("fixed")},$(function(){$(".chatbox .line[data-meta-conf=init]").css("display","block"),$("[data-meta-flag]").on("click",function(){var t=$(this).attr("data-meta-flag"),a=$(this).parent(".line.question");if(a.hasClass("disable"))$(this).removeClass("error").addClass("error");else{!function(t){switch(t){case"the-end":case"nekotora-magic":$(".chatbox").slideUp();break;case"do-another-style":$("body").html('\n          <div class="container">\n            <h1>你好我是七娃Nekotora.</h1>\n            <h4>完了。</h4>\n          </div>\n        ')}}(t),a.addClass("disable"),$(this).addClass("selected"),$(".chatbox .loading").css("display","block"),$(`[data-meta-content=${t}]>*`).css("display","none"),$(`[data-meta-content=${t}]`).css("display","block");var e=0;$(`[data-meta-content=${t}]>*`).each(function(){var t=random(1e3,2e3);e+=t,$(".chatbox .loading").css("display","block"),setTimeout(()=>{$(this).fadeIn()},e)}),setTimeout(()=>{$(".chatbox .loading").css("display","none")},e)}})});var _hmt=_hmt||[];(function(){var hm=document.createElement("script");hm.src="https://hm.baidu.com/hm.js?d3b3b1b968a56124689d1366adeacf8f";var s=document.getElementsByTagName("script")[0];s.parentNode.insertBefore(hm,s)})();