Layout: rows and columns

Fields are stacked top to bottom. To put fields side by side, wrap them in a columns row. Every column has a span (out of 12) and holds its own stack of fields, so you can have three short fields on the left next to one tall field on the right:

{
  "type": "columns",
  "id": "row1",
  "config": { "align": "start", "justify": "start" },
  "columns": [
    { "id": "left",  "span": 8, "fields": [ { "type": "input", "id": "name", "model": "name", "label": "Name" }, { "type": "input", "id": "email", "model": "email", "label": "Email" } ] },
    { "id": "right", "span": 4, "fields": [ { "type": "textarea", "id": "bio", "model": "bio", "label": "About you" } ] }
  ]
}

• config.align: vertical alignment of the columns, start center end or stretch.
• config.justify: where a row whose spans add up to less than 12 sits, start center or end (e.g. a single centered span: 6 column).
• Rows can't be nested. A row can have logic to show or hide all of it, and columns stack on narrow screens.
• The old per-field width (layout.cols) is still understood: adjacent partial-width fields are grouped into rows automatically when the schema loads.