/* 《沉浮》EP Hub — 沉浸分曲（参考 Apple 产品页节奏） */
body.hub-page {
  background: #07090b;
  color: #f5f5f7;
  overflow-x: hidden;
}

body.hub-page .nav {
  background: rgba(8, 10, 12, 0.72);
}
body.hub-page .nav-buy::before,
body.hub-page .btn-pill::before {
  display: none;
}
body.hub-page .cta-row {
  justify-content: flex-start;
  margin-top: 0;
}
body.hub-page .cta-row a {
  color: inherit;
}
body.hub-page .hero-mark {
  width: 48px;
  height: 48px;
  display: block;
  margin: 0 0 16px;
}
body.hub-page .hub-stage-copy .eyebrow {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  opacity: 0.7;
  color: rgba(245, 245, 247, 0.75);
}
body.hub-page .hub-stage-copy .subhead,
body.hub-page .hub-stage-copy .en {
  color: rgba(245, 245, 247, 0.72);
  margin-left: 0;
  margin-right: 0;
}

/* 氛围视频：有源时叠在静图上缓慢呼吸 */
.hub-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 1.2s ease;
  pointer-events: none;
}
.hub-video.is-ready {
  opacity: 0.68;
  mix-blend-mode: soft-light;
}
.hub-stage--hero .hub-video.is-ready {
  opacity: 0.5;
}
.hub-stage--track .hub-video.is-ready {
  opacity: 0.62;
  mix-blend-mode: overlay;
}

/* —— 全幅舞台 —— */
.hub-stage {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #f5f5f7;
}
.hub-stage--hero {
  align-items: end;
}
.hub-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hub-bg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.06);
  filter: saturate(0.92) contrast(1.05);
  will-change: transform;
  transition: transform 1.2s cubic-bezier(0.25, 0.1, 0.25, 1);
}
.hub-stage.is-in .hub-bg {
  transform: scale(1);
}
.hub-scrim {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(0,0,0,.18) 0%, rgba(0,0,0,.25) 40%, rgba(0,0,0,.78) 100%);
  pointer-events: none;
}
.hub-scrim--hero {
  background:
    radial-gradient(ellipse 70% 55% at 70% 30%, rgba(42,143,154,.22), transparent 58%),
    linear-gradient(180deg, rgba(0,0,0,.2) 0%, rgba(0,0,0,.55) 55%, rgba(0,0,0,.88) 100%);
}
.hub-scrim--blood {
  background:
    radial-gradient(ellipse 60% 50% at 30% 40%, rgba(196,30,58,.28), transparent 55%),
    linear-gradient(180deg, rgba(10,0,4,.25) 0%, rgba(0,0,0,.82) 100%);
}
.hub-scrim--mist {
  background:
    radial-gradient(ellipse 70% 60% at 60% 35%, rgba(160,190,200,.2), transparent 60%),
    linear-gradient(180deg, rgba(20,28,34,.2) 0%, rgba(12,16,20,.78) 100%);
}
.hub-scrim--ember {
  background:
    radial-gradient(ellipse 65% 55% at 75% 45%, rgba(232,90,36,.32), transparent 55%),
    linear-gradient(180deg, rgba(20,10,6,.25) 0%, rgba(0,0,0,.84) 100%);
}

.hub-canvas,
.hub-fx {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}
.hub-canvas { z-index: 1; opacity: .85; }
.hub-fx { z-index: 1; mix-blend-mode: soft-light; }

/* 概念动画层 */
.hub-fx--tide {
  background:
    radial-gradient(ellipse 40% 20% at 20% 80%, rgba(94,200,216,.25), transparent 70%),
    radial-gradient(ellipse 35% 18% at 80% 70%, rgba(42,143,154,.2), transparent 70%);
  animation: tideDrift 9s ease-in-out infinite alternate;
}
.hub-fx--caustic {
  background:
    repeating-linear-gradient(
      115deg,
      transparent 0 18px,
      rgba(120, 220, 230, 0.05) 18px 20px,
      transparent 20px 40px
    );
  animation: causticShift 7s linear infinite;
  opacity: .7;
}
.hub-fx--fin {
  background:
    linear-gradient(120deg, transparent 40%, rgba(255,90,110,.12) 50%, transparent 60%);
  background-size: 200% 100%;
  animation: finSweep 6.5s ease-in-out infinite;
}
.hub-fx--fog {
  background:
    radial-gradient(circle at 30% 40%, rgba(230,240,245,.18), transparent 40%),
    radial-gradient(circle at 70% 60%, rgba(180,200,210,.14), transparent 45%);
  animation: fogBreath 8s ease-in-out infinite;
}
.hub-fx--heat {
  background:
    radial-gradient(ellipse 50% 40% at 70% 60%, rgba(255,120,40,.22), transparent 60%);
  animation: heatPulse 4.8s ease-in-out infinite;
}

@keyframes tideDrift {
  from { transform: translate3d(-2%, 1%, 0) scale(1); }
  to { transform: translate3d(3%, -2%, 0) scale(1.05); }
}
@keyframes causticShift {
  from { background-position: 0 0; }
  to { background-position: 120px 40px; }
}
@keyframes finSweep {
  0%, 100% { background-position: 100% 0; opacity: .35; }
  50% { background-position: 0% 0; opacity: .7; }
}
@keyframes fogBreath {
  0%, 100% { opacity: .45; transform: scale(1); }
  50% { opacity: .8; transform: scale(1.08); }
}
@keyframes heatPulse {
  0%, 100% { opacity: .4; transform: scale(1); }
  50% { opacity: .85; transform: scale(1.06); }
}

.hub-stage-copy {
  position: relative;
  z-index: 3;
  padding: 0 clamp(22px, 6vw, 72px) clamp(48px, 10vh, 96px);
  max-width: 920px;
}
.hub-stage-copy .eyebrow,
.hub-stage-copy .num {
  letter-spacing: .22em;
  text-transform: uppercase;
  font-size: 12px;
  opacity: .7;
  margin: 0 0 12px;
}
.hub-stage-copy .headline {
  font-size: clamp(64px, 12vw, 120px);
  line-height: .9;
  margin: 0 0 10px;
  font-weight: 600;
  letter-spacing: -0.04em;
}
.hub-stage-copy .track-title {
  font-size: clamp(48px, 9vw, 92px);
  line-height: .92;
  margin: 0 0 8px;
  font-weight: 600;
  letter-spacing: -0.035em;
}
.hub-stage-copy .en {
  margin: 0 0 18px;
  opacity: .58;
  font-size: clamp(15px, 2vw, 20px);
  letter-spacing: .04em;
  text-transform: uppercase;
}
.hub-stage-copy .subhead,
.hub-stage-copy .pitch {
  max-width: 28em;
  margin: 0 0 28px;
  font-size: clamp(17px, 2.1vw, 22px);
  line-height: 1.45;
  opacity: .88;
}
.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 22px;
  align-items: center;
}
.ghost-link {
  color: rgba(245,245,247,.85) !important;
  text-decoration: none !important;
  font-size: 15px;
}
.ghost-link:hover { opacity: .7; }

.btn-pill--cyan { background: #2a8f9a; }
.btn-pill--cyan:hover { background: #1f6f78; }
.btn-pill--blood { background: #c41e3a; }
.btn-pill--blood:hover { background: #a81832; }
.btn-pill--mist { background: #5a7a88; }
.btn-pill--mist:hover { background: #3d5a66; }
.btn-pill--ember { background: #e85a24; }
.btn-pill--ember:hover { background: #c44718; }

/* 叙事弧 */
.hub-arc {
  padding: clamp(80px, 16vh, 160px) clamp(22px, 8vw, 96px);
  background: #07090b;
  text-align: center;
}
.arc-line {
  margin: 0 auto 28px;
  max-width: 16em;
  font-size: clamp(28px, 5vw, 48px);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.2;
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .9s var(--ease), transform .9s var(--ease);
}
.arc-line.is-in {
  opacity: 1;
  transform: none;
}

/* 曲目轨 */
.track-rail {
  position: sticky;
  top: 48px;
  z-index: 60;
  display: flex;
  gap: 4px;
  overflow-x: auto;
  padding: 10px 16px;
  background: rgba(8, 10, 12, 0.82);
  backdrop-filter: saturate(160%) blur(16px);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  border-bottom: 1px solid rgba(255,255,255,.06);
  scrollbar-width: none;
}
.track-rail::-webkit-scrollbar { display: none; }
.track-rail a {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: 980px;
  color: rgba(245,245,247,.7) !important;
  text-decoration: none !important;
  font-size: 13px;
  white-space: nowrap;
  transition: background .25s ease, color .25s ease;
}
.track-rail a span {
  opacity: .45;
  letter-spacing: .08em;
  font-size: 11px;
}
.track-rail a.is-on,
.track-rail a:hover {
  background: rgba(255,255,255,.08);
  color: #fff !important;
}

.hub-foot {
  padding: 72px 22px 96px;
  text-align: center;
  background: #050607;
  color: rgba(245,245,247,.55);
  font-size: 14px;
}
.hub-foot .eyebrow {
  letter-spacing: .18em;
  text-transform: uppercase;
  font-size: 11px;
  margin-bottom: 12px;
  opacity: .6;
}
.hub-foot-note {
  margin-top: 14px;
  opacity: .7;
}

@media (max-width: 720px) {
  .hub-stage-copy .headline { font-size: 56px; }
  .hub-stage-copy .track-title { font-size: 42px; }
  .arc-line { font-size: 26px; }
  .hub-stage-copy { padding: 0 18px 32px; }
  .cta-row { flex-wrap: wrap; gap: 14px; }
  .btn-pill { white-space: nowrap; }
}

@media (prefers-reduced-motion: reduce) {
  .hub-fx, .hub-bg, .arc-line { animation: none !important; transition: none !important; }
}