Build a linear, radial or conic gradient stop by stop with position sliders, then copy the CSS — which is re-parsed on the page to prove the output is valid.
Design a button's colours, padding, radius, border and shadow with a live preview, and get a measured WCAG contrast verdict on the text.
Build a complementary, analogous, triadic, split-complementary or monochromatic palette from one base colour, with the hue offsets shown and the best-contrast accent picked out.
Pair a display, body and code font from a curated Google Fonts list, see a live specimen at real modular-scale sizes, and copy the link tag and CSS.
Convert any number between bases 2 and 36, with binary, octal, decimal and hex side by side plus a Roman numeral readout.
Prime factorisation by trial division, every division step, the full divisor list, plus GCD and LCM of two numbers.
A real expression parser: tokenise, shunting-yard to postfix, then evaluate.
Build a wedding budget by category, track what is paid, and see what is still owed.
