Add missing #RRGGBBAA notation support

Author: hail2u

after/syntax/css/css-color-4.vim

@@ -1,4 +1,5 @@
 syn match cssColorProp contained "\<color-adjust\>"
 syn keyword cssColor contained rebeccapurple
+syn match cssColor contained "#[0-9A-Fa-f]\{8\}\>" contains=cssUnitDecorators
 syn region cssFunction contained matchgroup=cssFunctionName start="\<\(hwb\|lab\|lch\|gray\|color\|device-cmyk\|color-mod\=\)\s*(" end=")" oneline keepend
 syn match cssFontDescriptor "@color-profile\>" nextgroup=cssFontDescriptorBlock skipwhite skipnl

test/test.css

@@ -98,7 +98,8 @@
 }
 
 .color-4 {
-  color-adjust: rebeccapurple;
+  color-adjust: #FFEEDDFF;
+  display: rebeccapurple;
   display: hwb(120deg, 44%, 50%);
   display: lab(1 2 3);
   display: lch(4 5 6);

test/test.html

@@ -117,7 +117,8 @@
 }
 
 .color-4 {
-  color-adjust: rebeccapurple;
+  color-adjust: #FFEEDDFF;
+  display: rebeccapurple;
   display: hwb(120deg, 44%, 50%);
   display: lab(1 2 3);
   display: lch(4 5 6);