TITLE: Tempus — Hourglass Timer FILE: 088-hourglass-timer.html === PROMPT (exact prompt used) === Build "Tempus — Hourglass Timer", a beautiful focus timer with a physically simulated hourglass. Two glass bulbs drawn in SVG with realistic reflections inside a turned-wood and brass frame (#6b4226, #c9a227); sand simulated as particles (or a cellular sand grid) flowing through the neck: the top pile drains with a conical dip, a thin stream falls, and a mound builds in the lower bulb with grains tumbling down its slopes. Warm desert-glass palette: sand #e3b778, glass tint #e8f4f8, dusk background #2d1b3d → #d98d62. Set the duration with elegant preset chips (1, 5, 15, 25 min) or a custom input; the flow rate adapts so the sand runs out exactly on time. Click the hourglass (or a flip button) to flip it with a smooth 180° rotation — the sand keeps flowing with gravity reversed. Remaining time appears as a large, thin numeral with a progress arc; a gentle chime plays at the end (Web Audio). Pause/resume. Typography: classic serif numerals with old-style figures. SHARED REQUIREMENTS (apply to every page in this 100-page collection): 1. One standalone HTML5 file. All CSS inline in