Input
Short, single-line free text — reach for Textarea when the answer runs to sentences, and Select when it comes from a known set. Wrap it in Field for the label and description; a placeholder is an example of the answer, never a substitute for the label and never where required information lives.
Usage
Examples
Sizes
A 36 / 32 / 24px scale shared with Textarea, InputGroup and the date inputs, so a row
of mixed fields lines up. Reach below default only in dense places like a table filter.
Focused
Focus is a ring outside the border rather than a border change, so nothing reflows by a pixel when the reader tabs through a form.
Disabled
Dimmed and not focusable. Say elsewhere what would enable it — a disabled field with no explanation reads as broken.
With value
A filled field. Placeholder text is deliberately set at the same size as real input so the text doesn't jump when typing starts; only its colour is lighter.
With error
error reddens the border and sets aria-invalid. It shows that something is wrong but
not what — the message is FieldError's job.