CSS动画适用于Chrome和Safari，但不适用于Firefox和Internet Explorer

I have a simply css animation running on my website which should simply fade in various sections of my webpage at different times. Unfortunately, this aspect of my page works only in chrome and Safari, but not in Firefox and IE. After doing a little research, I included unit values for the fade timeframes, but this resulted in no improvement. Here is the following css:I have a simply css animation running on my web