CONTROLS: - Left-click/Scroll up/Up arrow: Increase gray level - Right-click/Scroll down/Down arrow: Decrease gray level - Click the gray level number: Type in a value (0-255) - Dropdown menu: Select step size (1, 5, or 15) - Grid toggle (⌗): Show/hide 3x3 grid overlay - ⟲ or R: Reset to the starting gray level, step and grid - ? or H: Show/hide this help USAGE: - Gray levels range from 0 (black) to 255 (white) - Use this tool to evaluate display gray scale - Current gray level shown in top right (zero-padded) - Step size controls increment/decrement amount - Grid overlay helps assess uniformity across display URL PARAMETERS: - ?gray=N - Set initial gray level (0-255) [default: 120] - ?step=N - Set initial step size (1, 5, or 15) [default: 15] - ?grid=true/false - Set initial grid state [default: false] - Example: grays.html?gray=128&step=5 - Example: grays.html?step=15&grid=true