:root {
  --bg: #05070a;
  --bg-2: #0a0e13;
  --panel: #0d1219;
  --text: #f2f7fa;
  --muted: #95a6b6;
  --accent: #8fe3ff;
  --accent-2: #4e9dff;
  --line: rgba(255, 255, 255, 0.13);
  --max: 1320px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

/* Lenis (bundle showroom-motion.min.js) — CSS bắt buộc của thư viện. */
html.lenis,
html.lenis body { height: auto; }
.lenis.lenis-smooth { scroll-behavior: auto !important; }
.lenis.lenis-smooth [data-lenis-prevent] { overscroll-behavior: contain; }
.lenis.lenis-stopped { overflow: hidden; }
.lenis.lenis-smooth iframe { pointer-events: none; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }

.topbar {
  position: fixed;
  inset: 0 0 auto 0;
  height: 64px;
  z-index: 60;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(1rem, 4vw, 3rem);
  background: linear-gradient(to bottom, rgba(5, 7, 10, 0.88), rgba(5, 7, 10, 0));
  backdrop-filter: blur(12px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  font-size: 0.78rem;
}

.brand em { color: var(--accent); font-style: normal; }

.brand-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 18px var(--accent);
}

.topbar nav {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  font-size: 0.78rem;
  color: var(--muted);
}

.topbar nav a:hover { color: var(--text); }

.shop-link {
  border: 1px solid var(--line);
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  color: var(--text);
}

.stage {
  position: relative;
  height: 520vh;
}

.stage-inner {
  position: sticky;
  top: 0;
  height: 100svh;
  overflow: hidden;
  background: #020304;
  /* Parallax 2.5D: JS ghi --sr-px/py/pr/ps khi rê chuột (tắt trên cảm ứng
     và khi prefers-reduced-motion). Mặc định 0 để máy không có JS vẫn đúng.
     --sr-ox/oy dành cho lớp vignette trôi chậm hơn nền. */
  --sr-px: 0px;
  --sr-py: 0px;
  --sr-pr: 0deg;
  --sr-ps: 1;
  --sr-ox: 0px;
  --sr-oy: 0px;
  --sr-os: 1;
}

.stage-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  /* Màu (sáng/tương phản/bão hoà) đã nướng vào video lúc encode —
     xem GRADE trong showroom/encode_final.py. Bỏ filter ở đây để trình
     duyệt khỏi lọc lại 1080p mỗi frame khi cuộn. */
  /* Video và lớp hotspot dùng CHUNG phép biến đổi → chấm luôn nằm trên
     sản phẩm, không trôi lệch khi rê chuột. */
  transform: translate3d(var(--sr-px), var(--sr-py), 0)
             scale(var(--sr-ps))
             rotate(var(--sr-pr));
  transform-origin: 50% 50%;
  will-change: transform;
}

.stage-vignette {
  position: absolute;
  inset: 0;
  /* v7.1: nhẹ hơn để nhìn rõ phòng; vẫn đủ tối ở mép cho chữ nổi. */
  background:
    linear-gradient(90deg, rgba(3, 5, 8, 0.40) 0%, rgba(3, 5, 8, 0) 40%, rgba(3, 5, 8, 0) 60%, rgba(3, 5, 8, 0.40) 100%),
    radial-gradient(ellipse at 50% 45%, rgba(0, 0, 0, 0) 38%, rgba(3, 5, 8, 0.34) 100%),
    linear-gradient(to bottom, rgba(3, 5, 8, 0.34), rgba(3, 5, 8, 0) 28%, rgba(3, 5, 8, 0) 68%, rgba(3, 5, 8, 0.55));
  pointer-events: none;
  /* Trôi chậm hơn nền để tạo chiều sâu; scale bù để không hở mép. */
  transform: translate3d(var(--sr-ox), var(--sr-oy), 0)
             scale(var(--sr-os));
  transform-origin: 50% 50%;
  will-change: transform;
}

/* ---------- đèn chớp ---------- */

/* Đèn phòng chớp rất nhẹ, đúng một nhịp mỗi 5 giây. */
.sr-flicker,
.stage-flicker {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: #02050a;
  opacity: 0;
  animation: sr-flicker 5s steps(1, end) infinite;
  will-change: opacity;
}

@keyframes sr-flicker {
  0%, 38%, 52%, 100% { opacity: 0; }
  40% { opacity: .035; }
  41% { opacity: .008; }
  42% { opacity: .05; }
  42.8% { opacity: .012; }
  43.8% { opacity: .03; }
  44.6% { opacity: 0; }
}

/* ---------- neon chạy trên biển "CLASSIC TECH" ---------- */

/* Vị trí + phép phối cảnh do sr-neon.js đặt mỗi frame; ở đây chỉ lo
   lớp phủ và dải sáng chạy bên trong mặt nạ chữ. */
.sr-neon,
.stage-neon {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  opacity: 0;
  transform: translate3d(var(--sr-px, 0px), var(--sr-py, 0px), 0)
             scale(var(--sr-ps, 1))
             rotate(var(--sr-pr, 0deg));
  transform-origin: 50% 50%;
  will-change: transform, opacity;
}

.sr-neon i,
.stage-neon i {
  position: absolute;
  left: 0;
  top: 0;
  width: 1000px;
  height: 88px;
  display: block;
  transform-origin: 0 0;
  -webkit-mask-size: 100% 100%;
  mask-size: 100% 100%;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
  mix-blend-mode: screen;
}
@supports (mix-blend-mode: plus-lighter) {
  .sr-neon i,
  .stage-neon i { mix-blend-mode: plus-lighter; }
}

/* Quầng sáng: cùng mặt nạ nhưng blur → ánh neon bung ra ngoài nét chữ.
   Khai báo sau @supports để thắng mix-blend-mode của lớp nét. */
.sr-neon i.sr-neon-halo,
.stage-neon i.sr-neon-halo {
  mix-blend-mode: screen;
  filter: blur(12px);
  opacity: 1;
}

/* Vet hong dam chay sau dai trang: doi mau ro khi den quet qua. */
.sr-neon i.sr-neon-tint,
.stage-neon i.sr-neon-tint {
  mix-blend-mode: screen;
  opacity: .6;
}
.sr-neon i.sr-neon-tint b,
.stage-neon i.sr-neon-tint b {
  width: 30%;
  animation-delay: .5s;
  background: linear-gradient(90deg,
    rgba(255, 40, 150, 0) 0%,
    rgba(255, 60, 165, .12) 26%,
    rgba(255, 50, 155, .55) 50%,
    rgba(255, 80, 175, .12) 74%,
    rgba(255, 40, 150, 0) 100%);
}

.sr-neon i.sr-neon-dim,
.stage-neon i.sr-neon-dim {
  background: #000;
  opacity: .12;
  mix-blend-mode: multiply;
}

.sr-neon b,
.stage-neon b {
  position: absolute;
  top: -10%;
  bottom: -10%;
  left: 0;
  width: 26%;
  display: block;
  background: linear-gradient(90deg,
    rgba(255, 255, 255, 0) 0%,
    rgba(255, 206, 228, .08) 28%,
    rgba(255, 245, 251, .42) 43%,
    rgba(255, 255, 255, 1) 50%,
    rgba(255, 240, 249, .42) 57%,
    rgba(255, 255, 255, 0) 72%);
  animation: sr-neon-run 2.4s cubic-bezier(.42, .02, .58, .98) infinite;
}

/* Quầng chạy chậm hơn một nhịp nhỏ → ánh sáng "trượt" khỏi nét, dày hơn. */
.sr-neon i.sr-neon-halo b,
.stage-neon i.sr-neon-halo b {
  width: 30%;
  animation-delay: -.1s;
}

@keyframes sr-neon-run {
  0%        { transform: translate3d(-130%, 0, 0); opacity: 0; }
  8%        { opacity: 1; }
  78%       { opacity: 1; }
  90%, 100% { transform: translate3d(250%, 0, 0); opacity: 0; }
}

@keyframes sr-neon-glow {
  0%, 100% { opacity: .88; }
  50%      { opacity: 1; }
}

/* QA chụp ảnh: đứng yên ở một pha cố định để ảnh tất định. */
.sr-neon.is-frozen b,
.stage-neon.is-frozen b {
  animation: none;
  opacity: 1;
  transform: translate3d(18%, 0, 0);
}
.sr-neon.is-frozen i,
.stage-neon.is-frozen i { animation: none; }

/* ---------- nhịp nối Góc 01 → Góc 02 ---------- */

/* Lấp khoảng 0,55–0,62 khi camera đổi bên: hai chương không còn rời nhau. */
.stage-bridge {
  position: absolute;
  left: 50%;
  top: clamp(5.2rem, 11vh, 7.5rem);
  width: min(600px, 78vw);
  text-align: center;
  pointer-events: none;
  opacity: 0;
  visibility: hidden;
  transform: translate(-50%, -10px);
  transition: opacity .4s ease, transform .5s cubic-bezier(.22, .61, .36, 1),
              visibility 0s linear .4s;
}

.stage-bridge.is-on {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, 0);
  transition: opacity .45s ease, transform .6s cubic-bezier(.22, .61, .36, 1);
}

/* Màn tối mềm phía sau để chữ đọc được cả khi nền có đèn/thùng máy. */
.stage-bridge::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 118%;
  height: 260%;
  transform: translate(-50%, -50%);
  background: radial-gradient(ellipse at center,
    rgba(2, 5, 10, .78) 0%,
    rgba(2, 5, 10, .45) 46%,
    rgba(2, 5, 10, 0) 72%);
  z-index: -1;
  pointer-events: none;
}

.stage-bridge-line {
  position: relative;
  display: block;
  width: 100%;
  height: 1px;
  margin: 0 0 1rem;
  background: linear-gradient(90deg,
    rgba(88, 182, 234, 0) 0%,
    rgba(88, 182, 234, .5) 22%,
    rgba(255, 255, 255, .85) 50%,
    rgba(88, 182, 234, .5) 78%,
    rgba(88, 182, 234, 0) 100%);
  transform: scaleX(0);
  transform-origin: 50% 50%;
  transition: transform .7s cubic-bezier(.22, .61, .36, 1);
}

.stage-bridge.is-on .stage-bridge-line { transform: scaleX(1); }

.stage-bridge-line i {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 6px;
  height: 6px;
  margin: -3px 0 0 -3px;
  border-radius: 50%;
  background: #e8f8ff;
  box-shadow: 0 0 10px 2px rgba(143, 227, 255, .8);
}

.stage-bridge-eyebrow {
  margin: 0 0 .45rem;
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--sky, #58b6ea);
}

.stage-bridge-eyebrow b {
  padding: 0 .45em;
  font-weight: 400;
  opacity: .55;
}

.stage-bridge-title {
  margin: 0;
  font-size: clamp(1.1rem, 1.6vw, 1.4rem);
  line-height: 1.35;
  letter-spacing: -.01em;
  color: #e7eef5;
  text-shadow: 0 2px 18px rgba(0, 0, 0, .6);
}

.stage-overlay {
  position: absolute;
  inset: 0;
  padding: clamp(5.5rem, 12vh, 9rem) clamp(1.2rem, 5vw, 4rem) clamp(4rem, 8vh, 6rem);
  pointer-events: none;
}

.scene {
  position: absolute;
  /* Giữ khối chữ hẹp hơn để không chồng lên biển neon "CLASSIC TECH" ở frame đầu. */
  max-width: min(600px, 82vw);
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.45s ease, transform 0.45s ease;
  pointer-events: none;
}

.scene.is-on {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.scene.intro { left: clamp(1.2rem, 5vw, 4rem); top: 16vh; }

.scene.intro::before {
  content: "";
  position: absolute;
  inset: -5rem -8rem -5rem -8rem;
  z-index: -1;
  pointer-events: none;
  background: radial-gradient(
    ellipse at 32% 50%,
    rgba(3, 5, 8, 0.92) 0%,
    rgba(3, 5, 8, 0.62) 46%,
    rgba(3, 5, 8, 0) 74%
  );
}

/* 2 cụm neo dải TRÊN: dải sản phẩm (y ~53–85%) để trống cho hotspot. */
.scene.side {
  left: clamp(1.2rem, 5vw, 4rem);
  top: 16vh;
  bottom: auto;
  max-width: min(520px, 80vw);
}
.scene.side.right { left: auto; right: clamp(1.2rem, 6vw, 5rem); text-align: right; }

.scene.side::before {
  content: "";
  position: absolute;
  inset: -3rem -5rem;
  z-index: -1;
  pointer-events: none;
  background: radial-gradient(
    ellipse at 30% 50%,
    rgba(3, 5, 8, 0.9) 0%,
    rgba(3, 5, 8, 0.55) 50%,
    rgba(3, 5, 8, 0) 78%
  );
}

.scene.side.right::before {
  background: radial-gradient(
    ellipse at 70% 50%,
    rgba(3, 5, 8, 0.9) 0%,
    rgba(3, 5, 8, 0.55) 50%,
    rgba(3, 5, 8, 0) 78%
  );
}

/* Tiêu đề cụm nhỏ hơn intro để không tràn xuống dải hotspot. */
.scene.side h2 {
  font-size: clamp(1.9rem, min(3.8vw, 6.2vh), 3.4rem);
}

/* Intro: ngắt dòng sớm để chữ không chồng lên biển neon "CLASSIC TECH". */
.scene.intro h1 { max-width: 520px; }

.scene.end {
  left: 50%;
  bottom: 14vh;
  transform: translate(-50%, -10px);
  text-align: center;
  max-width: min(700px, 88vw);
  padding: 1.2rem 1.6rem;
  border-radius: 28px;
  background: radial-gradient(ellipse at center, rgba(3, 5, 8, 0.7), rgba(3, 5, 8, 0) 72%);
}

.scene.end.is-on { transform: translate(-50%, 0); }

.eyebrow {
  margin: 0 0 1rem;
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
}

h1, h2, h3, p { margin-top: 0; }

h1 {
  margin-bottom: 1.2rem;
  /* height-aware: ở 900px cao, tiêu đề không được tràn xuống dải hotspot */
  font-size: clamp(2.6rem, min(9vw, 9.4vh), 7.4rem);
  line-height: 0.94;
  letter-spacing: -0.055em;
  font-weight: 650;
}

h1 span { color: var(--muted); }

h2 {
  margin-bottom: 1rem;
  font-size: clamp(2.2rem, 5.4vw, 4.6rem);
  line-height: 0.98;
  letter-spacing: -0.045em;
  font-weight: 620;
}

h3 {
  font-size: clamp(1.5rem, 2.6vw, 2.2rem);
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
}

.lede {
  max-width: 44ch;
  color: var(--muted);
  line-height: 1.65;
  font-size: clamp(0.95rem, 1.3vw, 1.12rem);
}

.scene.side.right .lede { margin-left: auto; }

.scene-actions, .viewer-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.6rem;
}

.scene.end .scene-actions { justify-content: center; }

.solid-btn, .ghost-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 48px;
  padding: 0.8rem 1.15rem;
  border-radius: 999px;
  font-size: 0.82rem;
  letter-spacing: 0.02em;
  border: 1px solid transparent;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.solid-btn {
  background: var(--accent);
  color: #04121a;
  font-weight: 700;
}

.ghost-btn {
  border-color: var(--line);
  color: var(--text);
  background: rgba(255, 255, 255, 0.03);
}

.solid-btn:hover, .ghost-btn:hover { transform: translateY(-2px); }
.ghost-btn:hover { border-color: rgba(143, 227, 255, 0.55); }

.scroll-hint {
  position: absolute;
  left: 50%;
  bottom: 1.4rem;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.62rem;
  letter-spacing: 0.32em;
  color: var(--muted);
  pointer-events: none;
}

.scroll-hint i {
  width: 1px;
  height: 42px;
  background: linear-gradient(var(--accent), transparent);
  animation: hint 1.8s ease-in-out infinite;
}

@keyframes hint {
  0%, 100% { transform: scaleY(0.35); opacity: 0.4; transform-origin: top; }
  50% { transform: scaleY(1); opacity: 1; transform-origin: top; }
}

.hotspots {
  position: absolute;
  inset: 0;
  pointer-events: none;
  /* Cùng transform với .stage-video — xem ghi chú ở đó. */
  transform: translate3d(var(--sr-px), var(--sr-py), 0)
             scale(var(--sr-ps))
             rotate(var(--sr-pr));
  transform-origin: 50% 50%;
  will-change: transform;
}

.hotspot {
  position: absolute;
  left: var(--x);
  top: var(--y);
  transform: translate(-50%, -50%);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s ease;
}

.hotspot.is-on { opacity: 1; pointer-events: auto; }

.hotspot button {
  position: relative;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 0;
  background: transparent;
  cursor: pointer;
  color: var(--text);
}

.hotspot .dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 6px rgba(143, 227, 255, 0.14), 0 0 24px rgba(143, 227, 255, 0.75);
}

.hotspot .label {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 0.55rem);
  transform: translateX(-50%) translateY(4px);
  min-width: 180px;
  padding: 0.75rem 0.9rem;
  border: 1px solid rgba(143, 227, 255, 0.22);
  border-radius: 12px;
  background: rgba(7, 12, 18, 0.9);
  backdrop-filter: blur(12px);
  text-align: left;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
}

.hotspot .label b { display: block; font-size: 0.8rem; line-height: 1.35; }
.hotspot .label span { display: block; margin-top: 0.2rem; color: var(--accent); font-size: 0.76rem; }

.hotspot button:hover .label,
.hotspot button:focus-visible .label,
.hotspot button:focus .label {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.hotspot button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
  border-radius: 50%;
}

.collection, .cta {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(4rem, 10vw, 8rem) clamp(1.2rem, 5vw, 3rem);
}

.collection {
  max-width: none;
  padding-top: clamp(4.5rem, 8vw, 7rem);
  padding-bottom: clamp(6rem, 10vw, 9rem);
  background: #0b1014;
  color: var(--text);
}

.collection-head,
.collection .product-grid {
  width: min(100%, var(--max));
  margin-left: auto;
  margin-right: auto;
}

.collection-head {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(240px, 0.65fr);
  align-items: end;
  gap: 3rem;
  max-width: var(--max);
  margin-bottom: clamp(3.5rem, 7vw, 6rem);
}

.collection .eyebrow {
  margin-bottom: 1.1rem;
  color: var(--accent);
  letter-spacing: 0.08em;
  text-transform: none;
}

.collection h2 {
  max-width: 10ch;
  margin: 0;
  color: var(--text);
  font-size: clamp(2.4rem, 5.3vw, 5rem);
  line-height: 0.96;
  font-weight: 520;
}

.collection .lede {
  align-self: end;
  max-width: 32ch;
  margin: 0 0 1.25rem;
  color: #92a0aa;
}

.collection-index {
  display: block;
  color: #71808a;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0 1.2rem;
}

.product-card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 0;
  padding: 0 0 2.6rem;
  border: 0;
  border-top: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 0;
  background: transparent;
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.product-card:hover { border-color: var(--accent); }
.product-card:nth-child(1),
.product-card:nth-child(2) { grid-column: span 2; }

.product-num {
  padding: 0.75rem 0 0.9rem;
  font-size: 0.66rem;
  letter-spacing: 0.12em;
  color: #71808a;
}

.product-media {
  display: grid;
  place-items: center;
  aspect-ratio: 1;
  height: auto;
  margin: 0 0 1.25rem;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 0;
  background: #f4f2ed;
  overflow: hidden;
}

.product-card:nth-child(1) .product-media,
.product-card:nth-child(2) .product-media { height: auto; }

.product-media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  mix-blend-mode: multiply;
  transition: transform 0.35s cubic-bezier(.2,.7,.2,1);
}

.product-card:hover .product-media img { transform: scale(1.045); }

.product-card h3 {
  max-width: 24ch;
  color: var(--text);
  font-size: 1.02rem;
  line-height: 1.3;
  margin: 0 0 0.45rem;
}

.product-card:nth-child(1) h3 { font-size: 1.25rem; }
.product-price { color: var(--accent); font-size: 0.82rem; margin-bottom: 1rem; }

.product-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: auto;
}

.product-actions button, .product-actions a {
  min-height: 0;
  padding: 0;
  border: 0;
  border-bottom: 1px solid currentColor;
  border-radius: 0;
  background: transparent;
  color: #d4dde2;
  font: inherit;
  font-size: 0.72rem;
  cursor: pointer;
}

.product-actions button { color: var(--accent); }

.collection + .cta {
  background: #0b1014;
  border-top-color: rgba(255, 255, 255, 0.12);
}

.collection + .cta h2 { color: var(--text); }
.collection + .cta .lede { color: #92a0aa; }

.cta {
  text-align: center;
  border-top: 1px solid var(--line);
  padding-bottom: 6rem;
}

.cta .lede { margin: 0 auto 1.4rem; }

.viewer {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: clamp(0.8rem, 3vw, 2rem);
  background: rgba(2, 4, 6, 0.78);
  backdrop-filter: blur(12px);
}

.viewer[hidden] { display: none; }

.viewer-panel {
  position: relative;
  width: min(980px, 100%);
  max-height: 92svh;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(260px, 0.8fr);
  border: 1px solid var(--line);
  border-radius: 24px;
  overflow: hidden;
  background: #080c11;
  box-shadow: 0 30px 120px rgba(0, 0, 0, 0.6);
}

.viewer-canvas-wrap {
  position: relative;
  min-height: 420px;
  background:
    radial-gradient(circle at 50% 40%, rgba(143, 227, 255, 0.12), transparent 55%),
    #070a0e;
}

#viewer-canvas { width: 100%; height: 100%; display: block; }

.viewer-info { padding: clamp(1.4rem, 3vw, 2.4rem); display: flex; flex-direction: column; justify-content: center; }

.viewer-price { color: var(--accent); margin-bottom: 0.4rem; }

.viewer-close {
  position: absolute;
  top: 0.8rem;
  right: 0.9rem;
  z-index: 2;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: rgba(5, 7, 10, 0.7);
  color: var(--text);
  font-size: 1.35rem;
  line-height: 1;
  cursor: pointer;
}

body.viewer-open { overflow: hidden; }

.footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.4rem clamp(1.2rem, 5vw, 3rem);
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}

/* ---------- chỉ báo 4 chặng ---------- */

.chapters {
  position: absolute;
  left: clamp(1.2rem, 5vw, 4rem);
  bottom: clamp(1rem, 2.4vh, 1.8rem);
  z-index: 5;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.chapters .sr-chapter {
  position: relative;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
}

.chapters .sr-chapter i {
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: rgba(242, 247, 250, 0.38);
  transition: width 0.25s ease, background 0.25s ease, box-shadow 0.25s ease;
}

.chapters .sr-chapter.is-on i {
  width: 22px;
  background: var(--accent);
  box-shadow: 0 0 14px rgba(143, 227, 255, 0.75);
}

.chapters .sr-chapter span {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 4px);
  transform: translateX(-50%) translateY(4px);
  padding: 0.28rem 0.5rem;
  border-radius: 6px;
  background: rgba(4, 9, 15, 0.9);
  color: var(--text);
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.18s ease, transform 0.18s ease;
}

.chapters .sr-chapter:hover span,
.chapters .sr-chapter:focus-visible span {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.chapters .sr-chapter:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 999px;
}

/* ---------- nút âm thanh ---------- */

.sound-pill {
  position: absolute;
  right: clamp(1rem, 4vw, 3rem);
  bottom: clamp(1rem, 2.4vh, 1.8rem);
  z-index: 6;
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.62rem 1rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(5, 10, 16, 0.72);
  backdrop-filter: blur(12px);
  color: var(--text);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
}

.sound-pill:hover {
  border-color: rgba(143, 227, 255, 0.55);
  transform: translateY(-2px);
}

.sound-pill:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.sound-pill.is-on {
  border-color: rgba(143, 227, 255, 0.65);
  background: rgba(12, 26, 38, 0.82);
  box-shadow: 0 0 22px rgba(143, 227, 255, 0.22);
}

.sound-pill-icon {
  font-size: 0.95rem;
  line-height: 1;
}

@media (max-width: 560px) {
  .sound-pill-text { display: none; }
  .sound-pill { padding: 0.7rem; }
}

/* Mobile / reduced motion: bỏ video scroll, dùng poster + grid */
@media (max-width: 768px) {
  .stage { display: none; }
  .topbar { height: 56px; background: rgba(5, 7, 10, 0.92); }
  .topbar nav a:first-child { display: none; }
  .collection { padding-top: 5.5rem; }
  .collection-head { grid-template-columns: 1fr; gap: 1.4rem; }
  .collection .eyebrow { margin-bottom: 1rem; }
  .product-grid { grid-template-columns: 1fr; }
  .product-card:nth-child(1),
  .product-card:nth-child(2) { grid-column: auto; }
  .product-card { min-height: 0; }
  .product-media,
  .product-card:nth-child(1) .product-media { height: auto; }
  .viewer-panel { grid-template-columns: 1fr; max-height: 92svh; overflow-y: auto; }
  .viewer-canvas-wrap { min-height: 300px; height: 42svh; }
}

@media (prefers-reduced-motion: reduce) {
  .stage { display: none; }
  .collection { padding-top: 5.5rem; }
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}

@media (max-width: 1100px) {
  .product-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .product-card:nth-child(1),
  .product-card:nth-child(2) { grid-column: span 2; }
}

@media (max-width: 820px) {
  .product-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .scene.side.right { text-align: left; left: clamp(1.2rem, 5vw, 4rem); right: auto; }
}

/* Tắt hiệu ứng khi người dùng bật "giảm chuyển động" bằng class của site. */
.reduce-fx .sr-flicker,
.reduce-fx .sr-neon,
.reduce-fx .stage-flicker,
.reduce-fx .stage-neon { display: none; }

/* v6.10 — sàn cỡ chữ 12px trên điện thoại.
   Đo thực tế ở 320–600px: `.scroll-hint` 9,92px; `.product-num` 10,56;
   `.collection-index` 10,88; `.eyebrow` và nút trong `.product-actions` 11,52.
   Desktop giữ nguyên. */
@media (max-width: 900px) {
  .eyebrow,
  .collection-index,
  .product-num,
  .product-actions button,
  .product-actions a,
  .scroll-hint,
  .chapters .sr-chapter span,
  .footer span,
  .footer a,
  .sound-pill,
  .sound-pill-text { font-size: .75rem; }
}