Answers for "how to remove border of button"

remove button default border css

button:focus { outline: none; }

how to remove border on button click

.btnName{
	outline: none;
}

removing the unwanted border button css

button,
button:active,
button:focus {
  outline: none;
}

html button remove border on click

.x-btn:focus, .button:focus, [type="submit"]:focus {
   outline: none;
}