LightScreen

LightScreen is a free browser tool that fills a monitor, laptop, or phone with any color at adjustable brightness. Use it as a screen flashlight, reading light, ambient light, or red light for stargazing. Extra modes include breathing, RGB cycle, traffic-light blink, a ring light, and Zoom lighting. A screen test page shows solid colors for dead pixels and backlight bleed. It also includes small fullscreen utilities: a digital clock, a Linux terminal simulator, a QR code on screen, and harmless fake call or update screens. Nothing is installed and no account is required. LightScreen is designed for creators, students, remote workers, photographers, and anyone who needs simple, instant illumination from a display.