corner-start-start-shape

An experimental property to set the shape of the corner at the start of both the block and inline axes (usually the top-left corner).

It is documented as part of the CSS Backgrounds and Borders specification. This is an experimental technology. The syntax and behavior are still subject to change.

/* Usage Example */
.modern-button {
  /* Experimental: sets specific shape for top-left corner */
  corner-start-start-shape: angle;
}

/* Global values */
corner-start-start-shape: inherit;
corner-start-start-shape: initial;
corner-start-start-shape: revert;
corner-start-start-shape: revert-layer;
corner-start-start-shape: unset;
Limited availability Since 2020 67% global usage

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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