How to determine if the power level of Xiaomi Wireless Keyboard and Mouse Combo is too low?

When the keyboard is low on battery, the orange light will flash for 3 seconds after the keyboard is switched on or woken up from hibernation to indicate battery replacement. When the mouse is low on power, the centre seam light will flash orange for 10 seconds after the mouse is switched on or wakes up from hibernation to prompt for battery replacement.