神奇3D圣诞树祝广大技术人员圣诞快乐！

 全部代码:

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div { margin: 0; padding: 0; border: 0; }
.nav { position: absolute; top: 0; left: 0; width: 100%; height: 27px; background-color: white; color: black; text-align: center; line-height: 25px;
}
a { color: black; text-decoration: none; border-bottom: 1px dashed black; }
a:hover { border-bottom: 1px solid red; }
.previous { float: left; margin-left: 10px; }
.next { float: right; margin-right: 10px; }
.green { color: green; }
.red { color: red; }
textarea { width: 100%; height: 100%; border: 0; padding: 0; margin: 0; padding-bottom: 20px; }
.block-outer { float: left; width: 22%; height: 100%; padding: 5px; border-left: 1px solid black; margin: 30px 3px 3px 3px; }
.block-inner { height: 68%; }
.one { border: 0; }
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</script><script>// start of submission //
M=Math;Q=M.random;J=[];U=16;T=M.sin;E=M.sqrt;for(O=k=0;x=z=j=i=k<200;)with(M[k]=k?c.cloneNode(0):c){width=height=k?32:W=446;with(getContext('2d'))if(k>10|!k)for(font='60px Impact',V='rgba(';I=i*U,fillStyle=k?k==13?V+'205,205,215,.15)':V+(147+I)+','+(k%2?128+I:0)+','+I+',.5)':'#cca',i<7;)beginPath(fill(arc(U-i/3,24-i/2,k==13?4-(i++)/2:8-i++,0,M.PI*2,1)));else for(;x=T(i),y=Q()*2-1,D=x*x+y*y,B=E(D-x/.9-1.5*y+1),R=67*(B+1)*(L=k/9+.8)>>1,i++<W;)if(D<1)beginPath(strokeStyle=V+R+','+(R+B*L>>0)+',40,.1)'),moveTo(U+x*8,U+y*8),lineTo(U+x*U,U+y*U),stroke();for(y=H=k+E(k++)*25,R=Q()*W;P=3,j<H;)J[O++]=[x+=T(R)*P+Q()*6-3,y+=Q()*U-8,z+=T(R-11)*P+Q()*6-3,j/H*20+((j+=U)>H&Q()>.8?Q(P=9)*4:0)>>1]}setInterval(function G(m,l){A=T(D-11);if(l)return(m[2]-l[2])*A+(l[0]-m[0])*T(D);a.clearRect(0,0,W,W);J.sort(G);for(i=0;L=J[i++];a.drawImage(M[L[3]+1],207+L[0]*A+L[2]*T(D)>>0,L[1]>>1)){if(i==2e3)a.fillText('Merry Christmas!',U,345);if(!(i%7))a.drawImage(M[13],((157*(i*i)+T(D*5+i*i)*5)%W)>>0,((113*i+(D*i)/60)%(290+i/99))>>0);}D+=.02},1)
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