みやすいように改行しています。

nemui.js

d=document;
[a,g,_,t,r,c,b,a.style,a.innerText]=[d.createElement('h1'),'background','center','transform','rotateX',d.createElement('style'),d.body,'animation:q 2s infinite','ねむい'];
x=`@keyframes q{from{${g}:red;${t}:${r}(0deg)}to{${g}:blue;${t}:${r}(90deg)scale(8)}}`;
b.style=`display:flex;justify-content:${_};align-items:${_}`;
f=(x,y)=>x.append(y);f(c,x);f(b,c);f(b,a);

nemui2.js

d=document;[a,g,_,t,r,c,b,a.style,a.innerText]=[d.createElement('h1'),'background','center','transform','rotateX',d.createElement('style'),d.body,'animation:q 2s infinite','ねむい'];x=`@keyframes q{from{${g}:red;${t}:${r}(0deg)}to{${g}:blue;${t}:${r}(90deg)scale(8)}}`;b.style=`display:flex;justify-content:${_};align-items:${_}`;f=(x,y)=>x.append(y);f(c,x);f(b,c);f(b,a);