Jonas Lossl was forced into an early save in the 5th minute, denying Glen Murray's header from five yards out before the assistant flagged the Scotsman offside.
Huddersfield took an early lead from a set piece in the 12th minute - Chris Lowe's corner was flicked on at the near post by Christopher Schindler to allow that man Mounie to bundle home at the back post for his first home goal.
Mounie then grabbed his second of the game in a very similar fashion to his first. Ryan punched Lowe's corner clear, Aaron Mooy whipped the ball back in to Mathias Jorgensen, who nodded it towards the Beninese striker for a header from close range that Ryan will be disappointed he couldn't keep out.
He's done it again! That man Steve Mounié has doubled Town's lead! (CL) pic.twitter.com/EjwIqhFtiO— Huddersfield Town (@htafcdotcom) December 9, 2017
The goal came at the perfect time for t
Brighton weren't in the game at all, and Hughton tried to switch things up in the 63rd minute by bringing on record signing Jose Izquierdo for Pascal Gross, moving Brown in behind. He then rolled the dice again ten minutes later, putting Tomer Hemed alongside Murray in place of Brown, who's name the Town fans sang as he departed the pitch.
Smith almost made it three as he drove inside and curled an effort just round the post - Huddersfield relentlessly kept knocking on the door.
However, Hughton's changes came to no avail and the game finished 2-0.
TEAM NEWS with @ViessmannUK: Head Coach David Wagner has made three changes to his #htafc starting line-up for today's @premierleague game against @OfficialBHAFC; 3pm kick-off.— Huddersfield Town (@htafcdotcom) December 9, 2017
➡️Jonathan Hogg, Chris Löwe and Steve Mounié (AT) pic.twitter.com/HOOF3EeuXv