:root {
  color-scheme: dark;
  --page-bg: #050403;
  --frame: #d6a84f;
  --frame-dark: #5f3f17;
  --ink: #f6e7bd;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 18%, rgba(115, 77, 28, 0.42), transparent 34%),
    linear-gradient(180deg, #17110a 0%, #050403 70%);
  color: var(--ink);
  font-family: "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, sans-serif;
  /* 扫描线效果 */
  background-image:
    repeating-linear-gradient(0deg, rgba(0,0,0,0.03) 0px, rgba(0,0,0,0.03) 2px, transparent 2px, transparent 4px);
}

.game-shell {
  width: 100vw;
  height: 100vh;
  display: grid;
  place-items: center;
  padding: 12px;
}

.game-shell:fullscreen {
  padding: 0;
  background: #050403;
}

#gameCanvas {
  display: block;
  image-rendering: pixelated;
  image-rendering: crisp-edges;

  /* 双层像素边框 */
  border: 4px solid var(--frame);
  outline: 3px solid var(--frame-dark);
  outline-offset: 0;

  background: #080704;
  box-shadow:
    0 0 0 2px #1d1308,
    0 24px 80px rgba(0, 0, 0, 0.72),
    inset 0 0 60px rgba(0, 0, 0, 0.3);

  cursor: crosshair;
  touch-action: none;
}

/* 游戏容器微光 */
.game-shell {
  position: relative;
}
.game-shell::after {
  content: "";
  position: absolute;
  inset: -4px;
  border: 1px solid rgba(214, 168, 79, 0.1);
  pointer-events: none;
}

.fallback-text {
  position: fixed;
  left: 12px;
  bottom: 8px;
  margin: 0;
  color: rgba(246, 231, 189, 0.46);
  font-size: 11px;
  pointer-events: none;
  letter-spacing: 0.5px;
}

@media (max-width: 640px) {
  .game-shell {
    padding: 6px;
  }
  #gameCanvas {
    border-width: 2px;
  }
}