body{-webkit-animation:-amp-start8ssteps(1,end)0s1normalboth;-moz-animation:-amp-start8ssteps(1,end)0s1normalboth;-ms-animation:-amp-start8ssteps(1,end)0s1normalboth;animation:-amp-start8ssteps(1,end)0s1normalboth}@-webkit-keyframes-amp-start{from{visibility:hidden}to{visibility:visible}}@-moz-keyframes-amp-start{from{visibility:hidden}to{visibility:visible}}@-ms-keyframes-amp-start{从{visibility:hidden}到{visibility:visible}}@-o-keyframes-amp-start{from{visibility:hidden}到{visibility:visible}}@keyframes-amp-start{from{可见性：隐藏}到{可见性：可见}}

HelloAMPWorld!