/* ============================================================
   X SPACE — 背景特效层 (FX)
   A 噪点 · B 发光网格 · C 鼠标光晕 · D 滚动视差
   E 扫描线 · F 粒子流 · G 极光漂移
   ============================================================ */

.fx-layer { position: fixed; inset: 0; pointer-events: none; z-index: 0; }
body > .bar, body > .frame, body > section, body > footer { position: relative; z-index: 1; }

/* A. 噪点纹理 */
.fx-noise-layer {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mix-blend-mode: overlay; opacity: 0.16;
}

/* B. 发光网格 + 呼吸 */
.fx-grid-layer {
  background-image:
    linear-gradient(rgba(255,215,0,0.10) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,215,0,0.10) 1px, transparent 1px);
  background-size: 48px 48px;
  animation: fx-grid-pulse 4s ease-in-out infinite;
}
@keyframes fx-grid-pulse { 0%,100% { opacity: .55; } 50% { opacity: 1; } }

/* C. 鼠标光晕 */
.fx-glow-layer {
  background: radial-gradient(
    600px circle at var(--mx, 50%) var(--my, 30%),
    rgba(255, 215, 0, 0.22), rgba(255, 215, 0, 0.06) 35%, transparent 60%
  );
}

/* D. 滚动视差 */
.hero-ghost {
  transform: translateY(calc(-50% + var(--pscroll, 0px) * 0.6)) rotate(calc(var(--pscroll, 0px) * 0.02deg)) !important;
  will-change: transform;
}
.hero-lead  { transform: translateY(calc(var(--pscroll, 0px) * 0.22));  will-change: transform; }
.hero-aside { transform: translateY(calc(var(--pscroll, 0px) * -0.1)); will-change: transform; }

/* E. 扫描线 + 滚动亮带 */
.fx-scan-layer {
  opacity: 0.6;
  background: repeating-linear-gradient(to bottom, rgba(0,0,0,0) 0, rgba(0,0,0,0) 2px, rgba(0,0,0,0.28) 3px, rgba(0,0,0,0) 4px);
}
.fx-scan-layer::after {
  content: ""; position: absolute; left: 0; right: 0; height: 140px;
  background: linear-gradient(to bottom, transparent, rgba(255,215,0,0.06), transparent);
  animation: fx-scanbar 6s linear infinite;
}
@keyframes fx-scanbar { from { top: -140px; } to { top: 100%; } }

/* F. 粒子流 / G. 极光 — canvas */
.fx-particles-canvas { opacity: 1; }
.fx-aurora-canvas { opacity: 0.85; }

/* 降低动效偏好：关闭动画类特效 */
@media (prefers-reduced-motion: reduce) {
  .fx-grid-layer, .fx-scan-layer::after { animation: none; }
  .hero-ghost, .hero-lead, .hero-aside { transform: none !important; }
  .fx-particles-canvas, .fx-aurora-canvas, .fx-scan-layer { display: none; }
}

/* ---- 触屏设备：无鼠标，关掉光晕（否则卡成静态光斑）---- */
@media (hover: none) {
  .fx-glow-layer { display: none; }
}

/* ---- 手机端：关掉视差（单列下大字与侧栏会反向位移重叠）+ 收细网格 ---- */
@media (max-width: 720px) {
  .hero-lead, .hero-aside { transform: none !important; }
  .hero-ghost { transform: translateY(-50%) !important; }
  .fx-grid-layer { background-size: 36px 36px; }
  .fx-noise-layer { opacity: 0.10; }       /* 小屏噪点收一点，免得糊字 */
  .fx-scan-layer { opacity: 0.4; }
}