Tyche is a static Hellenistic astrology chart creator built with plain HTML, CSS, and JavaScript.

It calculates a browser-side natal chart with:

• Tropical zodiac and Whole Sign Houses by default.
• The seven visible planets as the strict base set.
• Ascendant, MC, IC, sect, essential condition, lots, and configurations.
• English/Spanish UI.
• Day/night theme.
• Local serif typography and responsive mobile-first layout.

Planetary positions are calculated locally in the browser with vendored Astronomy Engine, an MIT-licensed JavaScript ephemeris library with approximate +/-1 arcminute accuracy. Critical charts should still be checked against professional ephemerides.