Units without leading 0s causes shadow color to not work.

[crswll]

What version of Tailwind CSS are you using?

3.0.14

What build tool (or framework if it abstracts the build tool) are you using?

Play

What version of Node.js are you using?

N/A

What browser are you using?

Chrome

What operating system are you using?

macOS

Reproduction URL

https://play.tailwindcss.com/sgiL9df2gw?file=config

Describe your issue

When using a value without a leading 0 for a box shadow the color won't be changed.

I took a shot at rewriting parseBoxShadowValue to get it to work because it seemed like a fun one to play around with. Ran the tests and it all passed. Didn't want to create a PR incase you had quicker, better fixes.

let KEYWORDS = ['inset', 'inherit', 'initial', 'revert', 'unset']
let COMMA = /\,(?![^(]*\))/g // Comma separator that is not located between brackets. E.g.: `cubiz-bezier(a, b, c)` these don't count.
let SPACE = /\ +(?![^(]*\))/g // Similar to the one above, but with spaces instead.

function parseBoxShadowValue (input) {
  let shadows = input.split(COMMA)

  return shadows.map(shadow => {
    let value = shadow.trim()
    let parts = value.split(SPACE)
    let output = { raw: value, valid: true }

    // A box-shadow requires at least 3 parts.
    if (parts.length < 3) {
      output.valid = false
      return output
    }

    // The color is always at the end, also a color can't start with a number or a .
    if (/^[\d.]/.test(parts[parts.length - 1])) {
      output.valid = false
      return output
    }

    if (KEYWORDS.includes(parts[0])) {
      output.keyword = parts.shift()
    }

    output.color = parts.pop()
    output.x = parts.shift()
    output.y = parts.shift()
    output.blur = parts.shift()
    output.spread = parts.shift()
    output.unknown = parts

    return output
  })
}