Gauge Card Pro is a Home Assistant Lovelace custom card that renders highly customizable gauge visualizations. It extends the native HA Gauge card with dual gauge layers (main and inner), gradient and severity modes, climate control features (HVAC, fan, swing, preset, temperature), template support, and a full visual editor. The card is built as a Lit web component and integrates deeply with Home Assistant's frontend, using internalized copies of HA and Mushroom dependencies for actions, entities, translations, and forms. Key entry points are `src/card/card.ts` (main card class) and `src/editor/editor.ts` (visual editor). Data flows from user configuration (YAML or UI) combined with HA entity state to compute gauge angles, gradient strings, indicators, and value displays. The system relies on external libraries like Lit, tinygradient, superstruct, and zod, and is distributed as a HACS plugin.