3.2 Transparency: the ‘opacity’ property

Chapter 3 - Color properties - 3.2 Transparency: the ‘opacity’ property

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t32-opacity-basic-0.0-a
opacity
Opacity of 0.0 makes box transparent.
t32-opacity-basic-0.6-a
opacity
Opacity of 0.6 makes box partially opaque. Colors are in sRGB color space (may test).
t32-opacity-basic-1.0-a
opacity
Opacity of 1.0 makes box fully opaque.
t32-opacity-clamping-0.0-b
opacity
Opacity values less than 0.0 are clamped to 0.0
t32-opacity-clamping-1.0-b
opacity
Opacity values greater than 1.0 are clamped to 1.0
t32-opacity-offscreen-b
opacity
That opacity specifies compositing the contents as a single offscreen buffer.
t32-opacity-offscreen-multiple-boxes-1-c
opacity
Opacity is group opacity over elements (not boxes).
t32-opacity-offscreen-multiple-boxes-2-c
opacity
Opacity is group opacity over elements (not boxes).
t32-opacity-offscreen-with-alpha-c
opacity
That alpha within the offscreen buffer is composited correctly.
t32-opacity-zorder-c
opacity
Opacity has z-ordering treatment of positioned elements and z-index applies.
will-change-stacking-context-opacity-1
CSS will-change: 'will-change: opacity' creates a stacking context
If any non-initial value of a property would create a stacking context on the element, specifying that property in will-change must create a stacking context on the element.