css3 - css 3问题， transition:0.5s all;是指所有属性？

Question

w3cSchool这样说的：

Answer 1

That’s pretty much what the questioner said, but let’s be clear, all refers to everything,

p{
    width: 200px;
    height: 200px;
    margin: 300px auto;
    background-color: #336699;
    
    transition: all 1s;
    /*transition: height 1s;*/
}
p:hover{
    width: 300px;
    height: 400px;
}

I think all here refers to the style after the transition. The above code runs and the width and height of p change smoothly. When we change all to height, only the height transformation process has animation effects. width is an instant change.

Answer 2

Yes, all can also be omitted without writing

Answer 3

Yes, it is recommended to specify a certain attribute when using it