remove(decl) {
    let params = this.parse(decl.value)
    params = params.filter(i => {
      let prop = this.prefixes.remove[this.findProp(i)]
      return !prop || !prop.remove
    })
    let value = this.stringify(params)

    if (decl.value === value) {
      return
    }

    if (params.length === 0) {
      decl.remove()
      return
    }

    let double = decl.parent.some(i => {
      return i.prop === decl.prop && i.value === value
    })
    let smaller = decl.parent.some(i => {
      return i !== decl && i.prop === decl.prop && i.value.length > value.length
    })

    if (double || smaller) {
      decl.remove()
      return
    }

    decl.value = value
  }
Process transition and remove all unnecessary properties