border-inline-start-width | CSS CSS Properties

Defines the thickness of the logical 'start' border. It's the modern way to set a left border that flips to the right in RTL languages.

Quick example

.side-accent {
  /* Logical left border thickness */
  border-inline-start-width: 8px;
  border-inline-start-style: solid;
  border-inline-start-color: #ec4899;
}

Quick facts

Initial value

medium

Inherited

Applies to

all elements

Animation type

byComputedValueType

Values

border-top-width

border-inline-start-width Browser Support

Widely available Since 2021 95% global usage

This feature is well established and works across many devices and browser versions. It has been available across browsers since 2021.

Safe to use without fallbacks.

View on caniuse.com → View on MDN → View on webstatus.dev → Learn more about Baseline →

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