Fix off-by-one error in 'css--hex-to-rgb'

* lisp/textmodes/css-mode.el (css--hex-to-rgb): Fix off-by-one error.

* test/lisp/textmodes/css-mode-tests.el (css-test-hex-to-rgb): Add
regression tests for the above fix.

1 files changed, 3 insertions, 1 deletions

diff --git a/test/lisp/textmodes/css-mode-tests.el b/test/lisp/textmodes/css-mode-tests.el
index 272d281217e..4883123843d 100644
--- a/test/lisp/textmodes/css-mode-tests.el
+++ b/test/lisp/textmodes/css-mode-tests.el
@@ -281,7 +281,9 @@
                   ("#fff" "rgb(255, 255, 255)")
                   ("#ffffff" "rgb(255, 255, 255)")
                   ("#ffffff80" "rgba(255, 255, 255, 0.5)")
-                  ("#fff8" "rgba(255, 255, 255, 0.5)")))
+                  ("#fff0" "rgba(255, 255, 255, 0)")
+                  ("#fff8" "rgba(255, 255, 255, 0.53)")
+                  ("#ffff" "rgba(255, 255, 255, 1)")))
     (with-temp-buffer
       (css-mode)
       (insert (nth 0 item))