Building Web Applications with SVG - Cdn.oreilly.com

4. Change the code so that just the outside of the circle is colored. This actually involves three
tasks: setting the fill of the circle to none so that its interior is transparent, setting its stroke
to some color (e.g., darkorange), and defining a width for the stroke. The code below also
adjusts the color from the named color darkorange to #e60, which is a bit lower on the
red channel and a good bit lower on the green channel than the darkorange hexadecimal
equivalent, #FF8C00.
5. Make the inside transparent. You can accomplish this by putting another opaque circle behind
it and scooting it a bit to the left. Note that the first object defined appears behind objects
that appear later in the document tree. In this case, we’ve also added another namespace
identifier (which is not strictly needed here, but will become necessary for elements that use
the SVG linking facilities to link to external documents or code fragments defined elsewhere
within the same document). It’s here so you can become accustomed to seeing it, because it’s
part of the standard declaration of a typical SVG document.
CHAPTER 1 SVG Basics 25