100 Square Calc: Add & Mul

10x10 simple 100 square calculation. It supports addition and multiplication, and can record time on a graph. Improves calculation skills and mental arithmetic skills, and helps train the brain. Functions/Features - Addition 100 Squares Calculation - Multiplication 100 Squares Calculation - Smooth numeric input - Measure your time - Record in graph - Display personal best/average time - Customization (dark mode, theme colors) - Simple design compliant with Material Design