/* HOME / blog index: Aurora + CTA sweep + card tilt (index-motion-a 相当) */

.hero-aurora {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.hero-aurora span {
  position: absolute;
  width: 55vmax;
  height: 55vmax;
  border-radius: 50%;
  filter: blur(40px);
  mix-blend-mode: screen;
  opacity: 0.28;
  animation: nanashinoAuroraFloat 16s ease-in-out infinite;
}

.hero-aurora span:nth-child(1) {
  background: #9f91ca;
  left: -10%;
  top: -10%;
}

.hero-aurora span:nth-child(2) {
  background: #ffffff;
  right: -18%;
  top: 18%;
  animation-delay: -4s;
}

.hero-aurora span:nth-child(3) {
  background: #d3c2db;
  left: 20%;
  bottom: -20%;
  animation-delay: -8s;
}

@keyframes nanashinoAuroraFloat {
  0%,
  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }
  50% {
    transform: translate3d(5%, -4%, 0) scale(1.12);
  }
}

.kv-hero__title-w1,
.kv-hero__title-w2 {
  background: linear-gradient(
    100deg,
    #ffffff,
    #f6ebff 40%,
    #fef5e6 70%,
    #ffffff
  );
  background-size: 240% auto;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  animation: nanashinoShimmerTitle 6s linear infinite;
}

@keyframes nanashinoShimmerTitle {
  0% {
    background-position: 0% 50%;
  }
  100% {
    background-position: 220% 50%;
  }
}

.kv-hero__cta {
  position: relative;
  overflow: hidden;
}

.kv-hero__cta::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    120deg,
    transparent 20%,
    rgba(255, 255, 255, 0.4) 50%,
    transparent 80%
  );
  transform: translateX(-140%);
  animation: kvCtaSweep 3.2s ease-in-out infinite;
  pointer-events: none;
}

@keyframes kvCtaSweep {
  0% {
    transform: translateX(-140%);
    opacity: 0;
  }
  22% {
    opacity: 1;
  }
  60% {
    opacity: 1;
  }
  100% {
    transform: translateX(140%);
    opacity: 0;
  }
}

.stream-panel,
.link-card,
.news-preview-card {
  transform-style: preserve-3d;
  will-change: transform;
  transition: transform 0.18s ease-out, box-shadow 0.18s ease-out;
}

@media (prefers-reduced-motion: reduce) {
  .hero-aurora span,
  .kv-hero__title-w1,
  .kv-hero__title-w2,
  .kv-hero__cta::after {
    animation: none !important;
  }
}