opacity()
The opacity() CSS function applies transparency to the samples in the input image. Its result is a <filter-function>.
Note: This function is similar to the more established opacity property. The difference is that with filters, some browsers provide hardware acceleration for better performance.
Syntax
opacity(amount)
Parameters
- amount
- 
    The amount of the conversion, specified as a <number>or a<percentage>. A value of0%is completely transparent, while a value of100%leaves the input unchanged. Values between0%and100%are linear multipliers on the effect. The lacuna value for interpolation is1.
Examples
Examples of correct values for opacity()
opacity(0%)   /* Completely transparent */
opacity(50%)  /* 50% transparent */
opacity(1)    /* No effect */
Specifications
| Specification | 
|---|
| Filter Effects Module Level 2 # funcdef-filter-opacity | 
Browser compatibility
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