mask-repeat

The mask-repeat CSS property sets how mask images are repeated. A mask image can be repeated along the horizontal axis, the vertical axis, both axes, or not repeated at all.

/* One-value syntax */
mask-repeat: repeat-x;
mask-repeat: repeat-y;
mask-repeat: repeat;
mask-repeat: space;
mask-repeat: round;
mask-repeat: no-repeat;

/* Two-value syntax: horizontal | vertical */
mask-repeat: repeat space;
mask-repeat: repeat repeat;
mask-repeat: round space;
mask-repeat: no-repeat round;

/* Multiple values */
mask-repeat: space round, no-repeat;
mask-repeat: round repeat, space, repeat-x;

/* Global values */
mask-repeat: inherit;
mask-repeat: initial;
mask-repeat: revert;
mask-repeat: unset;

By default, the repeated images are clipped to the size of the element, but they can be scaled to fit (using round) or evenly distributed from end to end (using space).

One or more <repeat-style> values, separated by commas.

<repeat-style>

The one-value syntax is a shorthand for the full two-value syntax:

Single value	Two-value equivalent
repeat-x	repeat no-repeat
repeat-y	no-repeat repeat
repeat	repeat repeat
space	space space
round	round round
no-repeat	no-repeat no-repeat

In the two-value syntax, the first value represents the horizontal repetition behavior and the second value represents the vertical behavior. Here is an explanation of how each option works for either direction:

repeat	The image is repeated as much as needed to cover the whole mask painting area. The last image will be clipped if it doesn't fit.
space	The image is repeated as much as possible without clipping. The first and last images are pinned to either side of the element, and whitespace is distributed evenly between the images. The mask-position property is ignored unless only one image can be displayed without clipping. The only case where clipping happens using space is when there isn't enough room to display one image.
round	As the allowed space increases in size, the repeated images will stretch (leaving no gaps) until there is room for another one to be added. When the next image is added, all of the current ones compress to allow room. Example: An image with an original width of 260px, repeated three times, might stretch until each repetition is 300px wide, and then another image will be added. They will then compress to 225px.
no-repeat	The image is not repeated (and hence the mask painting area will not necessarily be entirely covered). The position of the non-repeated mask image is defined by the mask-position CSS property.

<repeat-style>#
where 
<repeat-style> = repeat-x | repeat-y | [ repeat | space | round | no-repeat ]{1,2}

You can specify a different <repeat-style> for each mask image, separated by commas:

.examplethree {
  mask-image: url('mask1.png'), url('mask2.png');
  mask-repeat: repeat-x, repeat-y;
}

Each image is matched with the corresponding repeat style, from first specified to last.

• Clipping and Masking in CSS