void setStrokeColorHsl(
int h,
num s,
num l,
[num a = 1]
)

Sets the color used for stroking shapes. h is in degrees, 0-360. s, l are in percent, 0-100. a is 0-1.

Source

/**
 * Sets the color used for stroking shapes.
 * [h] is in degrees, 0-360.
 * [s], [l] are in percent, 0-100.
 * [a] is 0-1.
 */
void setStrokeColorHsl(int h, num s, num l, [num a = 1]) {
  this.strokeStyle = 'hsla($h, $s%, $l%, $a)';
}