:optional last modified: 20 October 2018
:optional
Basic Syntax of :optional
- :after/:before
- :active
- Adjacent sibling
- [attribute]
- :blank
- :checked
- Child
- Class
- :default
- :disabled
- Descendant
- :empty
- :enabled
- ::first-letter
- ::first-line
- :first-child
- :first-of-type
- :focus
- :focus-within
- General sibling
- :hover
- :in-range
- :indeterminate
- :invalid
- ID
- :lang()
- :last-child
- :last-of-type
- :link
- ::marker
- :matches()
- :not(s)
- :nth-child
- :nth-last-child
- :nth-last-of-type
- :nth-of-type
- :only-child
- :only-of-type
- :optional
- :out-of-range
- ::placeholder
- :placeholder-shown
- :read-write / :read-only
- :required
- :root
- ::selection
- :target
- Type
- :user-invalid
- Universal
- :valid
- :visited
- align-content
- align-items
- align-self
- all
- animation
- appearance
- backface-visibility
- background
- background-attachment
- background-blend-mode
- background-clip
- background-color
- background-image
- background-origin
- background-position
- background-repeat
- background-size
- bleed
- border
- border-collapse
- border-image
- border-radius
- bottom
- box-decoration-break
- box-shadow
- box-sizing
- break-inside
- caption-side
- clear
- clip-path
- color
- column-count
- column-fill
- column-gap
- column-rule
- column-span
- column-width
- columns
- content
- counter-increment
- counter-reset
- cursor
- direction
- display
- empty-cells
- fill
- filter
- flex
- flex-basis
- flex-direction
- flex-flow
- flex-grow
- flex-shrink
- flex-wrap
- float
- font
- font-display
- font-family
- font-feature-settings
- font-size
- font-size-adjust
- font-stretch
- font-style
- font-variant
- font-weight
- grid-row / grid-column
- grid-row-span / grid-column-span
- grid-rows / grid-columns
- hanging-punctuation
- height
- hyphens
- image-rendering
- initial-letter
- isolation
- justify-content
- left
- letter-spacing
- line-height
- list-style
- margin
- max-height
- max-width
- min-height
- min-width
- mix-blend-mode
- object-fit
- object-position
- offset-distance
- offset-path
- offset-rotation
- opacity
- order
- orphans
- outline
- outline-offset
- overflow
- overflow-anchor
- overflow-wrap
- padding
- page-break
- perspective
- perspective-origin
- pointer-events
- position
- quotes
- resize
- right
- scroll-behavior
- scrollbar
- shape-outside
- speak
- stroke
- stroke-dasharray
- stroke-dashoffset
- stroke-linecap
- stroke-width
- tab-size
- table-layout
- text-align
- text-align-last
- text-decoration
- text-decoration-color
- text-decoration-line
- text-decoration-skip
- text-decoration-style
- text-indent
- text-overflow
- text-rendering
- text-shadow
- text-stroke
- text-transform
- text-underline-position
- top
- transform
- transform-origin
- transform-style
- transition
- transition-delay
- transition-duration
- transition-property
- transition-timing-function
- unicode-bidi
- user-select
- vertical-align
- visibility
- white-space
- widows
- width
- will-change
- word-break
- word-spacing
- writing-mode
- z-index
- zoom