How to display colored text to players when they enter a certain area/coordinates

I made a map and I'm trying to make something like this:

I need a command that will run when anyone enters certain area/coordinates, it will display colored text. I tried every command that I guessed it will work.(/execute -/tellraw -/testfor) But it didn't work. This is another example of what I tried: **\tellraw** command (*Colored Text*)

An example of what I'm trying to do:

If anybody enters 10 60 10 to 50 60 10 coordinates, a red colored text will say: "You're about to fall down!"

What is a functioning command

Solution 1:

I might know! You have to do radius though, here is the command:

/execute @a[x=-30,y=60,z=10,r=2] ~ ~ ~ tellraw @p ["",{"text":"You're about to fall down!","color":"dark_red"}]

EDIT: You have to put it in a command block that is Repeat Unconditional and Always Active, you can put it anywhere.