To remove the outline on an input field, simply set the 'outline' property to 'none':
input {
outline: none;
}
Check out this JS Fiddle demo for a live example.
It's important to note that the outline is a visual cue for users to identify the currently active form element, so consider potential usability implications before removing it.
Update: Responding to a comment by Beakr, the OP, who wanted to experiment with modifying the outline:
I wanted to disable or customize it to explore different options.
If you want to customize the outline, you can adjust its individual properties like width, style, and color:
elementSelector:focus {
outline-width: 4px;
outline-style: auto;
outline-color: #f90;
}
For a more concise approach, use shorthand notation:
elementSelector:focus {
outline: 4px auto #f90;
}
You can also set the outline width to 'thin' or '1px' for a minimal outline effect:
elementSelector:focus {
outline-width: thin;
}