The flag of Czechia consists of two horizontal stripes and a blue isosceles triangle. The aspect ratio of the flag is 2:3.

Colors:

1. White (top stripe): HEX #FFFFFF, RGB(255, 255, 255)
2. Red (bottom stripe): HEX #D7141A, RGB(215, 20, 26)
3. Blue (triangle): HEX #11457E, RGB(17, 69, 126)

Geometric properties and measurements:

1. The white and red stripes are of equal height, each occupying half of the flag's total height.
2. The blue triangle has its base along the hoist side of the flag and extends to the midpoint of the opposite side.
3. The triangle's altitude is equal to the flag's height, and its base is equal to half of the flag's length.

No other specific measurements or relevant information are provided regarding the flag's design.