I want a cross-fading background for my home block portfolio
If viewport < 1000px
use small size picture(512x350)
else big size(1024x700)
bimg1 fadein, bimg2 fadeout
how to set the breakpoint, I want to set at 830, but it didn’t work. it just switch file randomly, not at the width=830px
if i run the program on ipad, it will still show the big size pictures for once, then switch to small size, any idea why?
here is my codepen link http://codepen.io/hsiangshen/pen/YGQNLE