:root {
  --bg: #14181f;
  --panel: #1d222b;
  --line: #2c333f;
  --fg: #e6ebf2;
  --muted: #8a93a3;
  --accent: #4aa3ff;
}
* { box-sizing: border-box; }
html, body {
  margin: 0; height: 100%;
  background: var(--bg); color: var(--fg);
  font: 14px/1.5 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
header.site {
  padding: 14px 20px; border-bottom: 1px solid var(--line);
  display: flex; align-items: baseline; gap: 16px;
}
header.site h1 { font-size: 16px; margin: 0; font-weight: 650; }
header.site nav { color: var(--muted); }
header.site nav a { margin-right: 14px; }

main { max-width: 1100px; margin: 0 auto; padding: 24px 20px; }
.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 10px; padding: 18px; margin-bottom: 18px;
}
.card h2 { margin: 0 0 6px; font-size: 15px; }
.muted { color: var(--muted); }

/* --- Sonic viewer --- */
.viewer-wrap { max-width: 1100px; margin: 0 auto; padding: 16px 20px; }
.viewport {
  /* Game Gear 10:9, capped by viewport height so it always fits on screen */
  position: relative; aspect-ratio: 10 / 9;
  width: min(100%, calc(60vh * 10 / 9)); margin: 0 auto;
  background: #000; border: 1px solid var(--line); border-radius: 8px;
  overflow: hidden; touch-action: none; cursor: grab;
}
.viewport.dragging { cursor: grabbing; }
.viewport canvas { display: block; width: 100%; height: 100%; image-rendering: pixelated; }
.hud {
  position: absolute; left: 8px; bottom: 8px;
  background: rgba(0,0,0,.55); color: #cfd6e0;
  padding: 3px 8px; border-radius: 6px; font: 12px ui-monospace, monospace;
  pointer-events: none;
}
.controls {
  display: flex; flex-wrap: wrap; gap: 14px 22px; align-items: center;
  padding: 12px 14px; margin-top: 12px;
  background: var(--panel); border: 1px solid var(--line); border-radius: 8px;
}
.controls label { display: inline-flex; align-items: center; gap: 6px; cursor: pointer; user-select: none; }
.controls select { background: var(--bg); color: var(--fg); border: 1px solid var(--line); border-radius: 6px; padding: 4px 8px; }
.controls .sep { width: 1px; align-self: stretch; background: var(--line); }
.controls .hint { color: var(--muted); margin-left: auto; }
.legend { margin-top: 12px; color: var(--muted); font-size: 13px; }
.legend b { color: var(--fg); font-weight: 600; }