L · 01 settings save per row on change; a busy row disables its control and shows an indicatorL · 02 description sits above the field, the error below it in red caption text that eases in through .form-reveal; one primary bottom-rightL · 03 two-column grids for personal info, collapsing to one column under 640pxL · 04 the composer is a one-row exception, paste-and-go, no labelsL · 05 block callouts are app.put.io's notification: info, success, warning, danger. Field errors carry no icon