mask element allows you to "clip" with soft edges. You can compose masks from multible elements including text. Everything of a mask that is white will be completely opaque. Everything that is black will be completely transparent. Values between white and black will be semi transparent.
SVG Fonts are not directly supported by Browsers any more. Still they are very convenient for programmatically generating fonts such as symbol fonts or barcode fonts.
There are many tools out there that allow you to convert svg fonts to any other font format.