backdrop-filter - CSS: Cascading Style Sheets
puted valueas specifiedanimation typea filter function list formal syntax none | <filter-function-list>where <filter-function-list> = [ <filter-function> | <url> ]+where <filter-function> = <blur()> | <brightness()> | <contrast()> | <drop-shadow()> | <grayscale()> | <hue-rotate()> | <invert()> | <opacity()> | <saturate()> | <sepia()>where <blur()> = blur( <length> )<brightness()> = brightness( <number-percentage> )<contrast()> = contrast( [ <number-percentage> ] )<drop-shadow()> = drop-shadow( <length>{2,3} <color>?
... )<grayscale()> = grayscale( <number-percentage> )<hue-rotate()> = hue-rotate( <angle> )<invert()> = invert( <number-percentage> )<opacity()> = opacity( [ <number-percentage> ] )<saturate()> = saturate( <number-percentage> )<sepia()> = sepia( <number-percentage> )where <number-percentage> = <number> | <percentage><color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>where <rgb()> = rgb( <percentage>{3} [ / <alpha-value> ]?

border-image-slice - CSS: Cascading Style Sheets
rder-image-slice: 10% 30%; /* top | horizontal | bottom */ border-image-slice: 30 30% 45; /* top | right | bottom | left */ border-image-slice: 7 12 14 5; /* using the `fill` keyword */ border-image-slice: 10% fill 7 12; /* global values */ border-image-slice: inherit; border-image-slice: initial; border-image-slice: unset; the border-image-slice property may be specified using one to four <number-percentage> values to represent the position of each image slice.
...it also applies to ::first-letter.inheritednopercentagesrefer to the size of the border imagecomputed valueone to four percentage(s) (as specified) or absolute length(s), plus the keyword fill if specifiedanimation typeby computed value type formal syntax <number-percentage>{1,4} && fill?where <number-percentage> = <number> | <percentage> examples adjustable border width and slice the folowing example shows a simple <div> with a border image set on it.

filter - CSS: Cascading Style Sheets
puted valueas specifiedanimation typea filter function list formal syntax none | <filter-function-list>where <filter-function-list> = [ <filter-function> | <url> ]+where <filter-function> = <blur()> | <brightness()> | <contrast()> | <drop-shadow()> | <grayscale()> | <hue-rotate()> | <invert()> | <opacity()> | <saturate()> | <sepia()>where <blur()> = blur( <length> )<brightness()> = brightness( <number-percentage> )<contrast()> = contrast( [ <number-percentage> ] )<drop-shadow()> = drop-shadow( <length>{2,3} <color>?
... )<grayscale()> = grayscale( <number-percentage> )<hue-rotate()> = hue-rotate( <angle> )<invert()> = invert( <number-percentage> )<opacity()> = opacity( [ <number-percentage> ] )<saturate()> = saturate( <number-percentage> )<sepia()> = sepia( <number-percentage> )where <number-percentage> = <number> | <percentage><color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>where <rgb()> = rgb( <percentage>{3} [ / <alpha-value> ]?

mask-border-slice - CSS: Cascading Style Sheets
al */ mask-border-slice: 10% 30%; /* top | horizontal | bottom */ mask-border-slice: 30 30% 45; /* top | right | bottom | left */ mask-border-slice: 7 12 14 5; /* using the `fill` keyword */ mask-border-slice: 10% fill 7 12; /* global values */ mask-border-slice: inherit; mask-border-slice: initial; mask-border-slice: unset; the mask-border-slice property may be specified using one to four <number-percentage> values to represent the position of each image slice.
... formal definition initial value0applies toall elements; in svg, it applies to container elements excluding the defs element and all graphics elementsinheritednopercentagesrefer to size of the mask border imagecomputed valueas specifiedanimation typediscrete formal syntax <number-percentage>{1,4} fill?where <number-percentage> = <number> | <percentage> examples basic usage this property doesn't appear to be supported anywhere yet.

CSS data types - CSS: Cascading Style Sheets
angle-percentage> <angular-color-hint> <angular-color-stop> <attr-fallback> <attr-name> <basic-shape> <blend-mode> <calc-product> <calc-sum> <calc-value> <color> <color-stop> <color-stop-angle> <counter-style> <custom-ident> <dimension> <filter-function> <flex> <frequency> <frequency-percentage> <gradient> <ident> <image> <integer> <length> <length-percentage> <number> <number-percentage> <percentage> <position> <quote> <ratio> <resolution> <shape-box> <shape-radius> <string> <time> <time-percentage> <timing-function> <toggle-value> <transform-function> <type-or-unit> <url> <url-modifier> <zero> specifications specification status comment css values and units module level 4 editor's draft css values and units module...