This is a fully configurable and client side gamma/brightness utility mod, making it much easier to see in the dark. It's a really basic mod that allows you to change the gamma value in game way higher than the in game brightness setting allows. Nights will look like day and caves will look like they're fully lit up. Basically Fullbright/Gammabright but for Fabric.

Toggle Gamma
Usage: Keybind (default: G) or /gamma toggle
Toggle between the default gamma percentage and the configured toggled percentage.

Increase Gamma
Usage: Keybind (default: arrow up) or /gamma increase (value is optional)
Increase the gamma percentage by the configured step percentage or the given value.

Decrease Gamma
Usage: Keybind (default: arrow down) or /gamma decrease (value is optional)
Decrease the gamma percentage by the configured step percentage or the given value.

Set Gamma
Usage: /gamma set
Set the gamma to a specific percentage.

Min Gamma
Usage: Keybind or /gamma min
Sets the gamma to the configured minimum limit.

Max Gamma
Usage: Keybind or /gamma max
Sets the gamma to the configured maximum limit.

Toggle Night Vision
Usage: Keybind (default: H) or /gamma nightvision
Toggle night vision on or off.

Default Gamma Percentage
Default: 100%
Gamma percentage for when the mod is toggled off.

Toggled Gamma Percentage
Default: 1500%
Gamma percentage for when the mod is toggled on.

Update Toggle Value
Default: false
Enabling this will make the toggle value remember the last non default value you've used.

Smooth Transition
Default: false
Make the transition when toggling gamma smoother.

Transition Speed
Default: 4500
Speed in gamma percentage per second.

Show Status Effect
Default: false
Show a status effect when the gamma percentage is outside normal range.
("Low Gamma" below 0% and "High Gamma" above 100%)

Limit Check
Default: true
Should the mod enforce the minimum and maximum gamma limits.

Minimum Gamma Limit
Default: -750%
Minimum gamma percentage the mod will allow if the Limit Check is enabled.

Maximum Gamma Limit
Default: 1500%
Maximum gamma percentage the mod will allow if the Limit Check is enabled.

Gamma Percentage Step
Default: 10%
Gamma percentage change for every increase or decrease.

Show Gamma Message
Default: true
Show a message with the new gamma value.

Reset on Close
Default: false
Reset the gamma value to default when Minecraft closes.

Required:
Fabric API
Cloth Config API Fabric (Is required to make the config work)

Optional:
Mod Menu (This mod allows you to edit the configs in game)