/* ============================================================
   Chọn Sẵn — Direction A (Tối giản tinh tế)
   Neutral có phân tầng. Chỉ CTA mang tương phản mạnh.
   System fonts để giữ cảm giác native + không phụ thuộc mạng.
   ============================================================ */

/* ===== Design Tokens ===== */
:root {
  /* Light */
  --bg: #fafafa;
  --surface: #ffffff;
  --surface-2: #f4f4f5;
  --text: #18181b;
  --muted: #6b6b74;
  --border: #e7e7ea;
  --accent: #18181b;
  --accent-fg: #ffffff;
  --ring: #2563eb;
  --badge-bg: #f4f4f5;
  --badge-fg: #52525b;
  --shadow-sm: 0 1px 2px rgba(24, 24, 27, 0.06);
  --shadow-md: 0 6px 16px rgba(24, 24, 27, 0.10);
  --scrim: rgba(24, 24, 27, 0.55);

  /* Gradient "magic pick" — 30deg, 3 màu, chuyển sắc tại chỗ (không chạy vị trí nên không seam) */
  --pick-grad: linear-gradient(30deg, #ff375f 0%, #bf5af2 50%, #0a84ff 100%);

  --font-sans: "Manrope", -apple-system, BlinkMacSystemFont, "SF Pro Text",
    "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;

  --text-xs: 0.75rem;
  --text-sm: 0.8125rem;
  --text-base: 0.9375rem;
  --text-lg: 1.0625rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;

  --radius-sm: 0.5rem;
  --radius: 0.75rem;
  --radius-md: 1rem;
  --radius-lg: 1.25rem;
  --radius-full: 999px;

  --ease: cubic-bezier(0.32, 0.72, 0, 1);
  --dur-fast: 180ms;
  --dur: 320ms;

  --topbar-h: 56px;
  --touch: 44px;
  --maxw: 1120px;
}

/* Dark — theo hệ thống, trừ khi bị ép bằng [data-theme] */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #09090b;
    --surface: #18181b;
    --surface-2: #27272a;
    --text: #fafafa;
    --muted: #a1a1aa;
    --border: #2a2a30;
    --accent: #fafafa;
    --accent-fg: #18181b;
    --ring: #60a5fa;
    --badge-bg: #27272a;
    --badge-fg: #d4d4d8;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 8px 22px rgba(0, 0, 0, 0.5);
    --scrim: rgba(0, 0, 0, 0.6);
  }
}
/* Ép theme (dùng cho QA / lựa chọn thủ công) */
:root[data-theme="dark"] {
  --bg: #09090b;
  --surface: #18181b;
  --surface-2: #27272a;
  --text: #fafafa;
  --muted: #a1a1aa;
  --border: #2a2a30;
  --accent: #fafafa;
  --accent-fg: #18181b;
  --ring: #60a5fa;
  --badge-bg: #27272a;
  --badge-fg: #d4d4d8;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 22px rgba(0, 0, 0, 0.5);
  --scrim: rgba(0, 0, 0, 0.6);
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; }

:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.skip-link {
  position: absolute;
  left: var(--space-4);
  top: -100px;
  z-index: 100;
  background: var(--accent);
  color: var(--accent-fg);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius);
  font-weight: 600;
  transition: top var(--dur-fast) var(--ease);
}
.skip-link:focus { top: var(--space-4); }

/* ===== Header ===== */
.site-header {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: calc(var(--space-6) + env(safe-area-inset-top, 0px)) var(--space-4) var(--space-5);
}

.identity {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.identity-text { min-width: 0; }
.avatar {
  flex: 0 0 auto;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--surface-2);
  border: 1px solid var(--border);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xl);
  font-weight: 750;
  letter-spacing: -0.02em;
}
.brand-sub {
  margin-top: var(--space-1);
  font-size: var(--text-sm);
  color: var(--muted);
  max-width: 34ch;
}

/* Header: hiệu ứng xuất hiện — avatar nảy nhẹ, text nổi lên mờ dần rõ (staggered blur-in) */
.avatar { animation: avatar-in 620ms var(--ease) both; }
.brand { animation: text-rise 640ms var(--ease) both; animation-delay: 90ms; }
.brand-sub { animation: text-rise 640ms var(--ease) both; animation-delay: 200ms; }

@keyframes avatar-in {
  from { opacity: 0; transform: scale(0.8); filter: blur(8px); }
  to { opacity: 1; transform: scale(1); filter: blur(0); }
}
@keyframes text-rise {
  from { opacity: 0; transform: translateY(14px); filter: blur(10px); }
  to { opacity: 1; transform: translateY(0); filter: blur(0); }
}

/* ===== Filter bar ===== */
.filter-bar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--border);
}
.filter-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: var(--space-3);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.filter-inner .seg { flex: 1 1 auto; min-width: 0; width: auto; }
.filter-inner .icon-btn { flex: 0 0 auto; }

.seg {
  position: relative;
  display: flex;
  width: 100%;
  gap: 2px;
  padding: 3px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  max-width: 100%;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}
.seg::-webkit-scrollbar { display: none; }

.seg-thumb {
  position: absolute;
  top: 3px;
  bottom: 3px;
  left: 0;
  width: 0;
  border-radius: var(--radius-full);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur) var(--ease), width var(--dur) var(--ease);
  pointer-events: none;
}

.seg-btn {
  position: relative;
  z-index: 1;
  flex: 1 1 0;
  min-width: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: var(--touch);
  padding: 0 var(--space-2);
  border: 0;
  background: transparent;
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
  white-space: nowrap;
  transition: color var(--dur-fast) var(--ease);
}
.seg-btn:hover { color: var(--text); }
.seg-btn[aria-pressed="false"] { color: var(--muted); }

.seg-count {
  display: none;
  font-size: var(--text-xs);
  font-weight: 700;
  min-width: 1.35em;
  text-align: center;
  padding: 1px 6px;
  border-radius: var(--radius-full);
  background: color-mix(in srgb, var(--text) 8%, transparent);
  color: var(--text);
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}
.seg-btn[aria-pressed="true"] .seg-count {
  background: var(--accent);
  color: var(--accent-fg);
}

/* Đủ chỗ: về kích thước tự nhiên + hiện số lượng */
@media (min-width: 560px) {
  .seg { display: inline-flex; width: max-content; }
  .filter-inner .seg { flex: 0 0 auto; }
  .seg-btn { flex: 0 0 auto; padding: 0 var(--space-3); }
  .seg-count { display: inline-block; }
  .filter-inner { justify-content: space-between; }
}

/* ===== Grid ===== */
main { flex: 1; width: 100%; }

.product-grid {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: var(--space-4) var(--space-4) var(--space-10);
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-3);
}

/* ===== Card ===== */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: transform var(--dur-fast) var(--ease),
              box-shadow var(--dur-fast) var(--ease);
  animation: card-in var(--dur) var(--ease) backwards;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.card:active { transform: scale(0.985); }

@keyframes card-in {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.card-media { position: relative; aspect-ratio: 1; background: var(--surface-2); overflow: hidden; }
/* Ảnh sản phẩm: mờ dần rồi hiện nét (blur reveal) */
.card-media img {
  width: 100%; height: 100%; object-fit: cover;
  opacity: 0;
  transform: scale(1.06);
  filter: blur(14px);
  transition: opacity 520ms var(--ease),
              transform 720ms var(--ease),
              filter 620ms var(--ease);
}
.card-media img.is-loaded { opacity: 1; transform: scale(1); filter: blur(0); }

.badge {
  display: none;
  position: absolute;
  top: var(--space-2);
  right: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 700;
  line-height: 1;
  padding: 5px 9px;
  border-radius: var(--radius-full);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
  color: var(--badge-fg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.badge-emoji {
  position: absolute;
  top: var(--space-2);
  left: var(--space-2);
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  font-size: 18px;
  line-height: 1;
  border-radius: var(--radius-full);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
  user-select: none;
}

.card-body {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  padding: var(--space-3);
  flex: 1;
}
.card-name {
  font-size: var(--text-base);
  font-weight: 650;
  letter-spacing: -0.01em;
  line-height: 1.3;
  min-height: calc(2 * 1.3em);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card-note {
  font-size: var(--text-sm);
  color: var(--muted);
  line-height: 1.35;
  margin-bottom: var(--space-3);
  display: -webkit-box;
  -webkit-line-clamp: 1;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* CTA — tương phản mạnh, nằm trên stretched link */
.card-cta,
.btn-primary {
  position: relative;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: var(--touch);
  border: 0;
  border-radius: var(--radius);
  background: var(--accent);
  color: var(--accent-fg);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.01em;
  transition: transform 120ms var(--ease), opacity var(--dur-fast) var(--ease);
}
.card-cta { margin-top: auto; }
.card-cta:hover,
.btn-primary:hover { opacity: 0.9; }
.card-cta:active,
.btn-primary:active { transform: scale(0.97); }
.card-cta svg,
.btn-primary svg { width: 1.05em; height: 1.05em; flex: 0 0 auto; }

/* Stretched link — cả card mở detail */
.card-link { position: absolute; inset: 0; z-index: 1; border-radius: var(--radius-md); }
.card-link:focus-visible { outline: 2px solid var(--ring); outline-offset: -2px; }

/* ===== Skeleton ===== */
.skeleton {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.skeleton .sk-media { aspect-ratio: 1; }
.skeleton .sk-body { padding: var(--space-3); display: flex; flex-direction: column; gap: var(--space-2); }
.skeleton .sk-line { height: 12px; border-radius: var(--radius-full); }
.skeleton .sk-line.w70 { width: 70%; }
.skeleton .sk-line.w45 { width: 45%; }
.skeleton .sk-btn { height: var(--touch); border-radius: var(--radius); margin-top: var(--space-2); }

.sk-media, .skeleton .sk-line, .skeleton .sk-btn {
  background: linear-gradient(100deg,
    var(--surface-2) 30%,
    color-mix(in srgb, var(--surface-2) 60%, var(--surface)) 50%,
    var(--surface-2) 70%);
  background-size: 220% 100%;
  animation: shimmer 1.4s linear infinite;
}
@keyframes shimmer {
  from { background-position: 180% 0; }
  to { background-position: -60% 0; }
}

/* ===== Empty state ===== */
.empty {
  grid-column: 1 / -1;
  text-align: center;
  color: var(--muted);
  padding: var(--space-10) var(--space-4);
  font-size: var(--text-sm);
}
.empty .btn-primary { margin-top: var(--space-4); padding: 0 var(--space-5); }

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: var(--space-8) var(--space-4)
    calc(var(--space-6) + 72px + env(safe-area-inset-bottom, 0px));
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-6);
}
/* Trang detail có sticky CTA (~76px) che đáy */
.page-detail .site-footer {
  padding-bottom: calc(var(--space-6) + 96px + env(safe-area-inset-bottom, 0px));
}

.socials { display: flex; gap: var(--space-2); }
.social-btn {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--surface);
  color: var(--text);
  transition: background var(--dur-fast) var(--ease),
              transform 120ms var(--ease);
}
.social-btn:hover { background: var(--surface-2); }
.social-btn:active { transform: scale(0.92); }
.social-btn svg { width: 20px; height: 20px; }

.disclosure {
  max-width: 620px;
  margin: 0 auto;
  text-align: center;
  font-size: var(--text-xs);
  line-height: 1.7;
  color: var(--muted);
}
.disclosure a { text-decoration: underline; text-underline-offset: 2px; }

/* ===== Detail ===== */
.detail-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--border);
}
.detail-header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--space-2);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.back-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  min-height: var(--topbar-h);
  padding: 0 var(--space-3);
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--text);
  transition: opacity var(--dur-fast) var(--ease);
}
.back-btn:hover { opacity: 0.6; }
.back-btn svg { width: 20px; height: 20px; }

.detail-main {
  flex: 1;
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  padding: var(--space-5) var(--space-4);
  padding-bottom: calc(var(--space-6) + 88px + env(safe-area-inset-bottom, 0px));
  animation: enter var(--dur) var(--ease) both;
}
@keyframes enter {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

.detail-media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--surface-2);
}
.detail-hero {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: var(--radius-lg);
  background: var(--surface-2);
  /* Cùng hiệu ứng mờ→nét với ảnh card */
  opacity: 0;
  transform: scale(1.06);
  filter: blur(14px);
  transition: opacity 520ms var(--ease),
              transform 720ms var(--ease),
              filter 620ms var(--ease);
}
.detail-hero.is-loaded { opacity: 1; transform: scale(1); filter: blur(0); }
.detail-name {
  font-size: var(--text-2xl);
  font-weight: 750;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-top: var(--space-5);
}
.detail-meta {
  margin-top: var(--space-2);
  font-size: var(--text-sm);
  color: var(--muted);
}
.detail-review {
  margin-top: var(--space-8);
  padding-top: var(--space-5);
  border-top: 1px solid var(--border);
}
.review-heading {
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: -0.01em;
}
.review-body {
  margin-top: var(--space-3);
  font-size: var(--text-base);
  line-height: 1.75;
  white-space: pre-line;
}
.review-groups {
  margin-top: var(--space-5);
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-5);
}
@media (min-width: 560px) {
  .review-groups { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
}
.review-group-title {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--muted);
}
.review-list {
  list-style: none;
  margin-top: var(--space-2);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.review-list li {
  display: flex;
  gap: var(--space-2);
  font-size: var(--text-base);
  line-height: 1.5;
}
.review-ico {
  flex: 0 0 auto;
  display: inline-grid;
  place-items: center;
  width: 22px;
  height: 22px;
  margin-top: 1px;
  border-radius: 50%;
  background: var(--surface-2);
  color: var(--text);
}
.review-ico svg { width: 12px; height: 12px; }
.review-list--cons .review-ico { color: var(--muted); }
.detail-disclosure {
  margin-top: var(--space-8);
  padding-top: var(--space-4);
  border-top: 1px solid var(--border);
  font-size: var(--text-xs);
  line-height: 1.7;
  color: var(--muted);
}
.detail-error {
  text-align: center;
  padding: var(--space-10) 0;
  color: var(--muted);
}
.detail-error .btn-primary { margin-top: var(--space-4); padding: 0 var(--space-5); }

/* ===== Sticky CTA ===== */
.sticky-cta {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  z-index: 30;
  padding: var(--space-3) var(--space-4) calc(var(--space-3) + env(safe-area-inset-bottom, 0px));
  background: color-mix(in srgb, var(--bg) 84%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-top: 1px solid var(--border);
  animation: dock-in 260ms var(--ease) both;
}
@keyframes dock-in {
  from { opacity: 0; transform: translateY(100%); }
  to { opacity: 1; transform: translateY(0); }
}
.sticky-cta .btn-primary {
  display: flex;
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  min-height: 50px;
  font-size: var(--text-base);
}

/* Đĩa tròn cho hiệu ứng đổi theme (theme.js định vị + tạo/xóa, không tương tác).
   Dùng transform: scale nên chạy trên GPU, không repaint toàn trang mỗi khung hình. */
.theme-veil {
  position: fixed;
  z-index: 9999;
  pointer-events: none;
  border-radius: 50%;
  transform-origin: center;
  will-change: transform;
  background: #fafafa;
}

/* ===== Icon button (theme toggle) ===== */
.icon-btn {
  display: inline-grid;
  place-items: center;
  width: var(--touch);
  height: var(--touch);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--surface);
  color: var(--text);
  transition: background var(--dur-fast) var(--ease),
              color var(--dur-fast) var(--ease),
              transform 120ms var(--ease);
}
.icon-btn:hover { background: var(--surface-2); }
.icon-btn:active { transform: scale(0.92); }
.icon-btn svg { width: 20px; height: 20px; }

.icon-sun { display: none; }
:root[data-theme="dark"] .icon-sun { display: block; }
:root[data-theme="dark"] .icon-moon { display: none; }

/* ===== Floating buttons ===== */
.fab {
  position: fixed;
  bottom: calc(var(--space-4) + env(safe-area-inset-bottom, 0px));
  z-index: 40;
  width: 54px;
  height: 54px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow-md);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
              background var(--dur-fast) var(--ease);
}
.fab:active { transform: scale(0.9); }
.fab svg { width: 23px; height: 23px; }
.fab-left { left: var(--space-4); }
.fab-right {
  right: var(--space-4);
  background: var(--accent);
  color: var(--accent-fg);
  border-color: transparent;
}

/* Back-to-top: ẩn cho tới khi cuộn */
.fab-left {
  opacity: 0;
  transform: translateY(14px) scale(0.9);
  pointer-events: none;
}
.fab-left.is-visible { opacity: 1; transform: none; pointer-events: auto; }

/* Magic pick */
.fab-right:disabled { opacity: 0.45; pointer-events: none; }
.fab-right::after {
  content: "";
  position: absolute;
  inset: -2px;
  border-radius: inherit;
  padding: 2px;
  background: var(--pick-grad);
  opacity: 0;
  pointer-events: none;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask-composite: exclude;
}
.fab-right.is-picking {
  border-color: transparent;
  animation: fab-spin 0.7s var(--ease);
}
/* Gradient nằm ở lớp ::before để filter hue-rotate không nhuộm icon */
.fab-right.is-picking::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: var(--pick-grad);
  animation: pick-flow 2.4s linear infinite;
  pointer-events: none;
}
.fab-right.is-picking svg { position: relative; z-index: 1; }
.fab-right.is-picking::after {
  animation: fab-ring 0.7s var(--ease), pick-flow 4s linear infinite;
}

@keyframes fab-spin {
  0% { transform: rotate(0) scale(1); }
  60% { transform: rotate(330deg) scale(1.09); }
  100% { transform: rotate(360deg) scale(1); }
}
@keyframes fab-ring {
  0% { opacity: 0.7; transform: scale(1); }
  100% { opacity: 0; transform: scale(1.9); }
}

/* Card nhấp nháy khi "quay số" — viền gradient động kiểu Apple */
@keyframes pick-flow {
  from { filter: hue-rotate(0deg); }
  to { filter: hue-rotate(360deg); }
}
.card.is-flash { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.card.is-chosen { transform: scale(1.03); box-shadow: var(--shadow-md); z-index: 2; }

.card.is-flash::after,
.card.is-chosen::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 3;
  padding: 2px;
  border-radius: inherit;
  background: var(--pick-grad);
  animation: pick-flow 9s linear infinite;
  pointer-events: none;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask-composite: exclude;
}
.card.is-chosen::after { padding: 3px; }

/* Đổi theme mượt (chỉ bật trong lúc chuyển) */
:root.theme-anim,
:root.theme-anim *,
:root.theme-anim *::before,
:root.theme-anim *::after {
  transition: background-color 0.3s ease, color 0.3s ease,
              border-color 0.3s ease !important;
}

/* ===== Shared element / page transition (progressive) ===== */
@view-transition { navigation: auto; }
::view-transition-old(root) { animation: vt-out 220ms var(--ease) both; }
::view-transition-new(root) { animation: vt-in 320ms var(--ease) both; }
@keyframes vt-out { to { opacity: 0; } }
@keyframes vt-in { from { opacity: 0; transform: translateY(8px); } }

/* ===== Responsive ===== */
@media (min-width: 640px) {
  .product-grid { grid-template-columns: repeat(3, 1fr); gap: var(--space-4); }
  .site-header { padding-top: var(--space-8); }
  .brand { font-size: var(--text-2xl); }
  .avatar { width: 56px; height: 56px; }
}
@media (min-width: 1024px) {
  .product-grid { grid-template-columns: repeat(4, 1fr); }
  .card-name { font-size: var(--text-base); }
}
@media (max-width: 360px) {
  .product-grid { grid-template-columns: 1fr; }
}

/* ===== Reduced motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .card:hover { transform: none; }
  ::view-transition-group(*), ::view-transition-old(*), ::view-transition-new(*) { animation: none !important; }
}