/* 基础层：重置、设计变量、全屏画布与氛围叠层 */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --cyan: #54e6ff;
  --violet: #a06bff;
  --gold: #ffd166;
  --red: #ff5c7a;
  --line: rgba(120, 190, 255, 0.2);
  --text: #e6f2ff;
}

html, body { height: 100%; }

body {
  background: #04060f;
  color: var(--text);
  font-family: "Segoe UI", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  overflow: hidden;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

#game {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
}

.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 5;
  background-image: repeating-linear-gradient(0deg, rgba(160, 220, 255, 0.035) 0 1px, transparent 1px 3px);
  opacity: 0.5;
  mix-blend-mode: overlay;
}

.vignette {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 6;
  background: radial-gradient(ellipse at 50% 45%, transparent 36%, rgba(2, 4, 10, 0.5) 78%, rgba(2, 4, 10, 0.92) 100%);
}