ID:2164740
 
(See the best response by Kaiochao.)
Code:
winset(src, "label", "text = \"<font color=red>Hello</font>\"")


Problem description: This doesn't change the font color of the text in a label to red, but instead prints the whole text in quotes... I know I can change the color of the text in the label via "Foreground" in appearance, but that changes the whole text's color and I'd like some words to be in different color than others...

winset(src, "label", "text-color = \"red\"")


That should work
Um, this still changes the font color of the whole text in the label... My example: ABC 123
How can I make ABC red and 123 blue!?
I'm not sure if skin elements work like that. You might have to redecorate it a bit and join two separate labels.
Best response
Labels don't support HTML, so they can only use one style at a time.

You can instead use an output element or a map element (using maptext on a HUD; this also enables mouse events).
obj
maptext
screen_loc = "10,10"//adjust to fit your screen
plane = 100//make it appear infront
maptext_width = 256
New()
..()
maptext = "<font color=red>ABC</font><font color=blue>123</font>"


mob
proc
maptext()
var/image/i = new/obj/maptext
src.client.screen+=i
sleep(20)
src.client.screen-=i

Use Maptext, it's the best and can more or less do what you're trying to do. Get familiar with it and use it all the time: http://www.byond.com/docs/ref/info.html#/atom/var/maptext