a. The blue border appears when the button and input are clicked to get the focus, how to remove it

a,button,input{

-webkit-tap-highlight-color: rgba(0, 0, 0, 0);

　　-webkit-user-modify: read-write-plaintext-only;

}

Can be added according to the actual situation

outline: none;

or

box-shadow: none;

Sometimes the <img /> image will also appear in the a tag, and the border of the image can be set to 0.

In addition, pay attention to the settings of its pseudo-class.

 

js method:

onclick="this.blur()"