Invert gravity

A simple endless runner in 560 characters of code. You have to invert gravity to skip the deadly spikes. Speed gets faster and faster. Press Z to invert gravity.

https://www.lexaloffle.com/bbs/?tid=37758

This game was made for #TweetTweetJam and contains only 560 characters of code, including art. The code is below:

_set_fps(60)h=0::s::p,x,y,z,b,t,e,f,g,l,m={},16,64,0,0,1,1,.02,.1,0,128
for i=1,900 do
p[i]=flr(rnd(3))end
::_::cls(1)t+=f
if(btn(4) and e>0)b,y,z,e=130-b,138-y,0,0
poke(24364,b)for i=0,m do
u=t+i/64
r=(m*u)%x
if(r>8)r=x-r
q=p[flr(u)]
if(b>0 and q>0)q=3-q
v=8*(sin(u)+sin(u/2))
c,w=3,104-v
if(q%2>0)w,c=w+r,12
rect(i,w,i,m,c)
if i==x then
if y<w then="" z+="g" y+="z" else="" y,z,e="w,0,1" if(c="=12)h=max(h,s)goto" s="" end="" c,w="3,24+v" if(band(q,2)="">0)w,c=w-r,12
rect(i,0,i,w,c)
end
?"웃",x,y-5,10
s=flr(t)
if(s>l)f,g,l=f+.001,g+.025,l+1
?"s: "..s.." h: "..h,0,0
flip()goto _