/* === 入场动画 === */

/* 淡入上浮基础 */
.fade-up {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s var(--ease-out),
              transform 0.7s var(--ease-out);
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 交错延迟 */
.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }
.delay-4 { transition-delay: 0.4s; }
.delay-5 { transition-delay: 0.5s; }

/* 缩放淡入 */
.fade-scale {
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.5s var(--ease-out),
              transform 0.5s var(--ease-out);
}

.fade-scale.visible {
  opacity: 1;
  transform: scale(1);
}

/* === 首屏Hero动画 === */
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

@keyframes pulse-ring {
  0%, 100% { transform: scale(1); opacity: 0.3; }
  50% { transform: scale(1.08); opacity: 0.15; }
}

@keyframes drift {
  0% { transform: translate(0, 0); }
  33% { transform: translate(20px, -10px); }
  66% { transform: translate(-15px, 15px); }
  100% { transform: translate(0, 0); }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-float {
  animation: float 6s ease-in-out infinite;
}

.hero-drift {
  animation: drift 20s linear infinite;
}

.hero-reveal-line {
  opacity: 0;
  animation: fadeInUp 0.8s var(--ease-out) forwards;
}

.hero-reveal-line:nth-child(1) { animation-delay: 0.2s; }
.hero-reveal-line:nth-child(2) { animation-delay: 0.4s; }
.hero-reveal-line:nth-child(3) { animation-delay: 0.6s; }
.hero-reveal-line:nth-child(4) { animation-delay: 0.8s; }

/* === 粒子光点 === */
.particles-container {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: rgba(255, 255, 255, 0.4);
  border-radius: 50%;
  animation: particleFloat 8s linear infinite;
}

@keyframes particleFloat {
  0% {
    transform: translateY(100vh) scale(0);
    opacity: 0;
  }
  10% {
    opacity: 1;
  }
  90% {
    opacity: 1;
  }
  100% {
    transform: translateY(-10vh) scale(1);
    opacity: 0;
  }
}

/* === 页面切换动画 === */
.page {
  animation: pageIn 0.4s var(--ease-out);
}

@keyframes pageIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}