`line-height-step` CSS property

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The line-height-step CSS property sets the step unit for line box heights. When the property is set, line box heights are rounded up to the closest multiple of the unit.

Syntax

/* Point values */
line-height-step: 18pt;

/* Global values */
line-height-step: inherit;
line-height-step: initial;
line-height-step: revert;
line-height-step: revert-layer;
line-height-step: unset;

Values

This property is specified as the following value:

<length>: The specified <length> is used in the calculation of the line box height step.

Formal definition

Initial value	0
Applies to	block containers
Inherited	yes
Computed value	absolute `<length>`
Animation type	by computed value type

Formal syntax

line-height-step = 
  <length>

Examples

Setting step unit for line box height

In the following example, the height of line box in each paragraph is rounded up to the step unit. The line box in <h1> does not fit into one step unit and thus occupies two, but it is still centered within the two step unit.

:root {
  font-size: 12pt;
  --my-grid: 18pt;
  line-height-step: var(--my-grid);
}
h1 {
  font-size: 20pt;
  margin-top: calc(2 * var(--my-grid));
}

The result of these rules is shown below in the following screenshot:

How the line-height-step property affects the appearance of text.

Specifications

Currently, no browsers support this feature.