Client borders:

    Expressions:
       
        #Changers: set (Location)
        #Info: The location ignores the y coordinate
        [client [side]] [world] border center [location] (for|of) %player%
        %player%'s [client [side]] [world] border center [location]
       
        #Changers: set, add, remove and reset (Number)
        #Info: Resetting it returns it to like how a new border would be made
        [client [side]] [world] border size (for|of) %player%
        %player%'s [client [side]] [world] border size
       
        #Changers: set, add, remove and reset (Number)
        #Info: Resetting it returns it to like how a new border would be made
        [client [side]] [world] border [damage] buffer (for|of) %player%
        %player%'s [client [side]] [world] border [damage] buffer
       
        #Changers: set, add, remove and reset (Number)
        #Info: Resetting it returns it to like how a new border would be made
        [client [side]] [world] border damage [amount] (for|of) %player%
        %player%'s [client [side]] [world] border damage [amount]
       
        #Changers: set, add, remove and reset (Integer)
        #Info: Resetting it returns it to like how a new border would be made
        [client [side]] [world] border warning [time] (for|of) %player%
        %player%'s [client [side]] [world] border warning [time]
       
        #Changers: set, add, remove and reset (Integer)
        #Info: Resetting it returns it to like how a new border would be made
        [client [side]] [world] border warning distance (for|of) %player%
        %player%'s [client [side]] [world] border warning distance

command /b:
    trigger:
        set client border warning distance of player to 100
        set client border center location of player to player's location
        broadcast "&6%client border center location of player%"
        broadcast "%client border size of player%"
        loop 20 times:
            set client border size of player to loop-number
            broadcast "%client border size of player%"
            wait a second
        reset client border warning distance of player