.yizhen-products-enhanced .main-nav a[href="/"] {
  color: inherit;
  font-weight: inherit;
}

.yizhen-products-enhanced .main-nav a[href="/"]::after { display: none; }

.yizhen-products-enhanced .main-nav a[href="/products"] {
  color: #061a42;
  font-weight: 700;
}

.yizhen-products-enhanced .main-nav a[href="/products"]::after {
  position: absolute;
  right: 18%;
  bottom: 4px;
  left: 18%;
  display: block;
  height: 3px;
  border-radius: 99px;
  background: #126cff;
  content: '';
}

.yizhen-products-enhanced .detail-hero {
  grid-template-columns: minmax(0, 1.12fr) minmax(350px, .88fr);
  min-height: 650px;
  padding-top: 76px;
}

.yizhen-products-enhanced .detail-hero__copy {
  max-width: 760px;
}

.yizhen-products-enhanced .detail-hero__copy > p:first-child {
  margin-bottom: 24px;
  font-size: 10px;
  letter-spacing: .24em;
}

.yizhen-products-enhanced .yizhen-product-hero-title {
  display: grid;
  gap: 2px;
  max-width: 760px;
  font-size: clamp(48px, 4.65vw, 68px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -.045em;
  padding-block: .06em .1em;
}

.yizhen-product-hero-title span,
.yizhen-product-hero-title strong {
  display: block;
  white-space: nowrap;
}

.yizhen-product-hero-title strong {
  color: #0a73e8;
  background: linear-gradient(98deg, #096fe4 4%, #18a8ef 48%, #7651e9 96%);
  background-clip: text;
  font: inherit;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.yizhen-product-hero-wave {
  display: flex;
  align-items: center;
  gap: clamp(7px, .75vw, 12px);
  width: min(100%, 640px);
  height: 58px;
  margin-top: 24px;
  overflow: hidden;
}

.yizhen-product-hero-wave::before,
.yizhen-product-hero-wave::after {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(44, 153, 239, .27));
  content: '';
}

.yizhen-product-hero-wave::after {
  background: linear-gradient(90deg, rgba(117, 80, 235, .27), transparent);
}

.yizhen-product-hero-wave i {
  flex: 0 0 2px;
  width: 2px;
  height: 14px;
  border-radius: 999px;
  background: linear-gradient(#8ed9ff, #9377f5);
  opacity: .42;
}

.yizhen-product-hero-wave i:nth-child(3n + 1) { height: 31px; opacity: .56; }
.yizhen-product-hero-wave i:nth-child(4n + 2) { height: 45px; opacity: .48; }
.yizhen-product-hero-wave i:nth-child(5n) { height: 23px; }

.yizhen-products-enhanced .detail-hero__copy > p:nth-of-type(2) {
  max-width: 660px;
  margin-top: 5px;
  font-size: 15px;
  line-height: 1.9;
  letter-spacing: .015em;
}

.yizhen-products-enhanced .detail-hero__actions { margin-top: 29px; }

.yizhen-model-tiers {
  width: min(1240px, calc(100% - 72px));
  margin: 76px auto 122px;
  border-top: 0;
}

.yizhen-model-tiers__header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, .88fr);
  gap: clamp(36px, 7vw, 100px);
  align-items: end;
  margin-bottom: 34px;
  padding: 0 4px;
}

.yizhen-model-tiers__header div > p {
  margin: 0 0 14px;
  color: #0870e8;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: .2em;
}

.yizhen-model-tiers__header h2 {
  max-width: 650px;
  margin: 0;
  color: #071b44;
  font-size: clamp(34px, 3.8vw, 52px);
  line-height: 1.08;
  letter-spacing: -.045em;
}

.yizhen-model-tiers__header > p {
  margin: 0;
  color: #5e7697;
  font-size: 14px;
  line-height: 1.85;
}

.yizhen-model-tiers__list { display: grid; gap: 18px; }

.yizhen-model-tier {
  --model-accent: #158ce9;
  --model-accent-rgb: 21, 140, 233;
  position: relative;
  display: grid;
  grid-template-columns: 82px minmax(0, 1fr) 286px;
  gap: 36px;
  align-items: center;
  min-height: 320px;
  padding: 34px 34px 32px;
  overflow: hidden;
  border: 1px solid rgba(87, 126, 179, .17);
  border-radius: 26px;
  outline: none;
  background: radial-gradient(circle at 90% 50%, rgba(var(--model-accent-rgb), .075), transparent 28%), rgba(255, 255, 255, .74);
  box-shadow: 0 12px 34px rgba(45, 83, 138, .045);
  transition: border-color 260ms ease, box-shadow 260ms ease, transform 260ms ease, background-color 260ms ease;
}

.yizhen-model-tier::before {
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: linear-gradient(transparent, var(--model-accent), transparent);
  opacity: .18;
  content: '';
  transition: opacity 260ms ease;
}

.yizhen-model-tier.is-scope { --model-accent: #6e50ed; --model-accent-rgb: 110, 80, 237; }
.yizhen-model-tier.is-spectra { --model-accent: #f28a31; --model-accent-rgb: 242, 138, 49; }

.yizhen-model-tier:hover,
.yizhen-model-tier:focus-visible {
  border-color: rgba(var(--model-accent-rgb), .32);
  background-color: rgba(255, 255, 255, .9);
  box-shadow: 0 26px 60px rgba(var(--model-accent-rgb), .11);
  transform: translateY(-3px);
}

.yizhen-model-tier:hover::before,
.yizhen-model-tier:focus-visible::before { opacity: .9; }
.yizhen-model-tier:focus-visible { outline: 2px solid rgba(var(--model-accent-rgb), .45); outline-offset: 3px; }

.yizhen-model-tier__meta {
  align-self: stretch;
  display: flex;
  flex-direction: column;
  gap: 9px;
  padding-top: 3px;
  border-right: 1px solid rgba(77, 119, 176, .13);
}

.yizhen-model-tier__meta span { color: var(--model-accent); font-size: 13px; font-weight: 800; letter-spacing: .16em; }
.yizhen-model-tier__meta strong { color: #173e70; font-size: 12px; }
.yizhen-model-tier__meta small { color: #7d91aa; font-size: 10px; }
.yizhen-model-tier__copy { min-width: 0; }

.yizhen-model-tier__copy > p:first-child {
  margin: 0 0 12px;
  color: var(--model-accent);
  font-size: 9px;
  font-weight: 800;
  letter-spacing: .18em;
}

.yizhen-model-tier__copy h3 {
  margin: 0;
  color: #092653;
  font-size: clamp(30px, 3vw, 43px);
  line-height: 1.08;
  letter-spacing: -.04em;
}

.yizhen-model-tier__copy h3 strong { color: var(--model-accent); font: inherit; }

.yizhen-model-tier__description {
  max-width: 610px;
  margin: 18px 0 0;
  color: #617897;
  font-size: 14px;
  line-height: 1.8;
}

.yizhen-model-tier__copy dl {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin: 25px 0 0;
  border-top: 1px solid rgba(78, 120, 175, .13);
}

.yizhen-model-tier__copy dl > div { min-width: 0; padding: 14px 14px 0 0; }
.yizhen-model-tier__copy dt { color: #8899ae; font-size: 9px; letter-spacing: .08em; }
.yizhen-model-tier__copy dd { margin: 6px 0 0; color: #264a77; font-size: 11px; font-weight: 700; line-height: 1.45; }

.yizhen-model-tier__visual {
  position: relative;
  display: grid;
  place-items: center;
  width: 286px;
  height: 258px;
  margin: 0;
}

.yizhen-model-tier__visual img {
  display: block;
  width: 258px;
  height: 258px;
  object-fit: contain;
  transition: opacity 360ms ease, filter 360ms ease, transform 420ms cubic-bezier(.22, 1, .36, 1);
}

.yizhen-model-tier__visual figcaption {
  position: absolute;
  right: 28px;
  bottom: 21px;
  left: 28px;
  display: grid;
  place-items: center;
  gap: 2px;
  color: #183e6f;
  text-align: center;
  transition: opacity 320ms ease, transform 320ms ease;
}

.yizhen-model-tier__visual figcaption strong { font-size: 15px; letter-spacing: .12em; }
.yizhen-model-tier__visual figcaption span { color: #7589a3; font-size: 9px; }

@media (hover: hover) and (pointer: fine) {
  .yizhen-model-tier__visual img {
    opacity: .2;
    filter: saturate(.28) grayscale(.24) brightness(1.13);
    transform: scale(.92);
  }
  .yizhen-model-tier__visual figcaption { opacity: .42; transform: translateY(3px); }
  .yizhen-model-tier:hover .yizhen-model-tier__visual img,
  .yizhen-model-tier:focus-visible .yizhen-model-tier__visual img {
    opacity: 1;
    filter: saturate(1.04) grayscale(0) brightness(1);
    transform: scale(1);
  }
  .yizhen-model-tier:hover .yizhen-model-tier__visual figcaption,
  .yizhen-model-tier:focus-visible .yizhen-model-tier__visual figcaption { opacity: 1; transform: translateY(0); }
}

.yizhen-products-performance {
  position: relative;
  z-index: 1;
  width: min(1320px, calc(100% - 72px));
  margin: -54px auto 100px;
  padding: clamp(36px, 5vw, 64px);
  overflow: hidden;
  border: 1px solid rgba(74, 121, 184, .18);
  border-radius: 30px;
  background:
    radial-gradient(circle at 92% 2%, rgba(32, 171, 238, .15), transparent 27%),
    linear-gradient(145deg, rgba(255, 255, 255, .98), rgba(240, 247, 255, .92));
  box-shadow: 0 30px 80px rgba(37, 81, 145, .09);
  color: #071b44;
}

.yizhen-products-performance::before {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(45, 107, 183, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(45, 107, 183, .035) 1px, transparent 1px);
  background-size: 58px 58px;
  content: '';
  pointer-events: none;
  mask-image: linear-gradient(115deg, #000, transparent 67%);
}

.yizhen-products-performance__header,
.yizhen-products-performance__grid,
.yizhen-products-performance__facts,
.yizhen-products-performance__note {
  position: relative;
  z-index: 1;
}

.yizhen-products-performance__header {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(420px, 1.1fr);
  gap: clamp(36px, 7vw, 96px);
  align-items: end;
  margin-bottom: 38px;
}

.yizhen-products-performance__header div > p {
  margin: 0 0 15px;
  color: #0870e8;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: .2em;
}

.yizhen-products-performance__header h2 {
  max-width: 560px;
  margin: 0;
  font-size: clamp(34px, 4vw, 56px);
  line-height: 1.16;
  letter-spacing: -.04em;
}

.yizhen-products-performance__header > p {
  max-width: 610px;
  margin: 0;
  color: #5b7394;
  font-size: 14px;
  line-height: 1.85;
}

.yizhen-products-performance__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.yizhen-performance-card {
  --metric-color: #ee724c;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 142px;
  gap: 20px;
  align-items: center;
  min-height: 224px;
  padding: 28px 24px 26px 28px;
  border: 1px solid rgba(65, 111, 174, .15);
  border-radius: 22px;
  background: rgba(255, 255, 255, .88);
  box-shadow: 0 16px 38px rgba(37, 78, 139, .07);
}

.yizhen-performance-card.is-violet { --metric-color: #7047ee; }
.yizhen-performance-card.is-blue { --metric-color: #0798e8; }
.yizhen-performance-card.is-pink { --metric-color: #ef438d; }

.yizhen-performance-card__copy { min-width: 0; }

.yizhen-performance-card__topline {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  color: #7890ab;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: .14em;
}

.yizhen-performance-card__topline span:last-child {
  color: var(--metric-color);
  letter-spacing: 0;
}

.yizhen-performance-card__value {
  margin: 25px 0 7px;
  color: var(--metric-color);
  font-size: clamp(45px, 4.5vw, 64px);
  font-weight: 790;
  line-height: 1.06;
  letter-spacing: -.06em;
}

.yizhen-performance-card__value small {
  margin-left: 4px;
  font-size: .32em;
  letter-spacing: 0;
}

.yizhen-performance-card h3 {
  margin: 0;
  color: #092856;
  font-size: 17px;
}

.yizhen-performance-card__sample {
  max-width: 250px;
  margin: 13px 0 0;
  color: #607897;
  font-size: 11px;
  line-height: 1.6;
}

.yizhen-performance-card__art {
  display: grid;
  place-items: center;
  width: 142px;
  height: 132px;
}

.yizhen-performance-card__art img {
  display: block;
  width: auto;
  height: auto;
  max-width: 132px;
  max-height: 118px;
  object-fit: contain;
  filter: saturate(1.12) contrast(1.05);
}

.yizhen-performance-card.is-orange .yizhen-performance-card__art img { max-width: 116px; max-height: 108px; }
.yizhen-performance-card.is-violet .yizhen-performance-card__art img { max-width: 126px; max-height: 102px; }
.yizhen-performance-card.is-blue .yizhen-performance-card__art img { max-width: 128px; max-height: 112px; }
.yizhen-performance-card.is-pink .yizhen-performance-card__art img { max-width: 110px; max-height: 110px; }

.yizhen-products-performance__facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin: 18px 0 0;
  border: 1px solid rgba(65, 111, 174, .14);
  border-radius: 17px;
  background: rgba(245, 250, 255, .82);
}

.yizhen-products-performance__facts > div {
  display: grid;
  gap: 7px;
  padding: 20px 25px;
}

.yizhen-products-performance__facts > div + div { border-left: 1px solid rgba(65, 111, 174, .14); }
.yizhen-products-performance__facts dt { color: #7c91aa; font-size: 9px; letter-spacing: .1em; }
.yizhen-products-performance__facts dd { margin: 0; color: #123c70; font-size: 15px; font-weight: 800; }

.yizhen-products-performance__note {
  margin: 17px 2px 0;
  color: #6a819e;
  font-size: 10px;
  line-height: 1.7;
}

.yizhen-products-performance + .detail-notice { margin-top: -52px; }

@media (max-width: 900px) {
  .yizhen-products-enhanced .detail-hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 70px;
  }
  .yizhen-products-enhanced .yizhen-product-hero-title { font-size: clamp(40px, 7.2vw, 58px); }
  .yizhen-products-enhanced .detail-signal { margin-top: -12px; }
  .yizhen-model-tiers { width: calc(100% - 36px); margin-top: 68px; }
  .yizhen-model-tiers__header { grid-template-columns: 1fr; gap: 17px; }
  .yizhen-model-tier { grid-template-columns: 70px minmax(0, 1fr); gap: 28px; }
  .yizhen-model-tier__visual { grid-column: 2; width: 250px; height: 230px; justify-self: center; }
  .yizhen-model-tier__visual img { width: 230px; height: 230px; }
  .yizhen-model-tier__visual figcaption { right: 24px; bottom: 18px; left: 24px; }
  .yizhen-products-performance { width: calc(100% - 36px); }
  .yizhen-products-performance__header { grid-template-columns: 1fr; gap: 18px; }
  .yizhen-products-performance__grid { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .yizhen-products-enhanced .detail-hero { padding-top: 58px; }
  .yizhen-products-enhanced .detail-hero__copy > p:first-child { margin-bottom: 17px; font-size: 9px; }
  .yizhen-products-enhanced .yizhen-product-hero-title {
    gap: 3px;
    font-size: clamp(28px, 8vw, 43px);
    line-height: 1.14;
    letter-spacing: -.045em;
  }
  .yizhen-product-hero-wave { gap: 6px; height: 46px; margin-top: 17px; }
  .yizhen-product-hero-wave i:nth-child(3n + 1) { height: 24px; }
  .yizhen-product-hero-wave i:nth-child(4n + 2) { height: 34px; }
  .yizhen-product-hero-wave i:nth-child(5n) { height: 18px; }
  .yizhen-products-enhanced .detail-hero__copy > p:nth-of-type(2) { margin-top: 2px; font-size: 13px; line-height: 1.75; }
  .yizhen-products-enhanced .detail-hero__actions { margin-top: 23px; }
  .yizhen-model-tiers { margin: 58px auto 86px; }
  .yizhen-model-tiers__header { padding: 0 2px; }
  .yizhen-model-tiers__header h2 { font-size: 34px; }
  .yizhen-model-tiers__header > p { font-size: 13px; line-height: 1.72; }
  .yizhen-model-tiers__list { gap: 14px; }
  .yizhen-model-tier {
    grid-template-columns: 1fr;
    gap: 20px;
    min-height: 0;
    padding: 24px 20px 18px;
    border-radius: 21px;
  }
  .yizhen-model-tier__meta {
    display: grid;
    grid-template-columns: auto auto 1fr;
    align-items: center;
    gap: 10px;
    padding: 0 0 16px;
    border-right: 0;
    border-bottom: 1px solid rgba(77, 119, 176, .13);
  }
  .yizhen-model-tier__meta small { justify-self: end; }
  .yizhen-model-tier__copy h3 { font-size: 34px; }
  .yizhen-model-tier__description { font-size: 13px; line-height: 1.72; }
  .yizhen-model-tier__copy dl { grid-template-columns: 1fr; margin-top: 20px; }
  .yizhen-model-tier__copy dl > div { padding-top: 11px; padding-bottom: 11px; border-bottom: 1px solid rgba(78, 120, 175, .1); }
  .yizhen-model-tier__visual { grid-column: 1; width: 100%; height: 230px; }
  .yizhen-model-tier__visual img { width: 228px; height: 228px; opacity: .9; }
  .yizhen-model-tier__visual figcaption { right: calc(50% - 88px); bottom: 18px; left: calc(50% - 88px); }
  .yizhen-products-performance {
    margin: -42px auto 78px;
    padding: 29px 18px 24px;
    border-radius: 24px;
  }
  .yizhen-products-performance__header { margin-bottom: 25px; }
  .yizhen-products-performance__header h2 { font-size: 36px; }
  .yizhen-products-performance__header > p { font-size: 13px; line-height: 1.75; }
  .yizhen-performance-card {
    grid-template-columns: minmax(0, 1fr) 96px;
    gap: 10px;
    min-height: 180px;
    padding: 22px 13px 21px 20px;
    border-radius: 18px;
  }
  .yizhen-performance-card__topline { display: grid; gap: 5px; }
  .yizhen-performance-card__value { margin-top: 20px; font-size: 46px; }
  .yizhen-performance-card__sample { margin-top: 10px; font-size: 10px; }
  .yizhen-performance-card__art { width: 96px; height: 100px; }
  .yizhen-performance-card__art img { max-width: 92px; max-height: 88px; }
  .yizhen-performance-card.is-orange .yizhen-performance-card__art img { max-width: 84px; max-height: 80px; }
  .yizhen-performance-card.is-violet .yizhen-performance-card__art img { max-width: 90px; max-height: 76px; }
  .yizhen-performance-card.is-blue .yizhen-performance-card__art img { max-width: 92px; max-height: 84px; }
  .yizhen-performance-card.is-pink .yizhen-performance-card__art img { max-width: 82px; max-height: 82px; }
  .yizhen-products-performance__facts { grid-template-columns: 1fr; }
  .yizhen-products-performance__facts > div { padding: 16px 19px; }
  .yizhen-products-performance__facts > div + div { border-top: 1px solid rgba(65, 111, 174, .14); border-left: 0; }
  .yizhen-products-performance + .detail-notice { margin-top: -36px; }
}

/* Model system: three related symbols, increasing analytical depth. */
.yizhen-model-tiers {
  width: min(1240px, calc(100% - 72px));
  margin: 86px auto 112px;
  border-top: 0;
}

.yizhen-model-tiers__header {
  display: block;
  padding: 0 0 36px;
  border-bottom: 1px solid #dce6f2;
}

.yizhen-products-enhanced .detail-hero__copy > .yizhen-model-introduction {
  max-width: 740px;
  font-size: 15px;
  line-height: 1.82;
}

.yizhen-model-introduction span { display: block; }

.yizhen-model-tiers__header div > p {
  margin: 0 0 14px;
  color: #4a78ae;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .17em;
}

.yizhen-model-tiers__header h2 {
  max-width: none;
  margin: 0;
  color: #0a2049;
  font-size: clamp(36px, 3.3vw, 48px);
  line-height: 1.2;
  letter-spacing: -.035em;
}

.yizhen-model-tiers__header > p {
  max-width: 850px;
  margin: 21px 0 0;
  color: #607696;
  font-size: 15px;
  line-height: 1.95;
}

.yizhen-model-tiers__header > p strong {
  display: block;
  color: #27486f;
  font-weight: 650;
}

.yizhen-model-tiers__list { display: grid; gap: 0; }

.yizhen-model-tier {
  --model-ink: #1874bf;
  --model-soft: #e8f4fc;
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr) 190px;
  align-items: center;
  gap: 34px;
  min-height: 226px;
  padding: 29px 0;
  overflow: visible;
  border: 0;
  border-bottom: 1px solid #dce6f2;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
  transform: none;
}

.yizhen-model-tier::before { display: none; }
.yizhen-model-tier.is-scope { --model-ink: #486bc4; --model-soft: #edf1fd; }
.yizhen-model-tier.is-spectra { --model-ink: #7463bb; --model-soft: #f2effa; }

.yizhen-model-tier:hover {
  border-color: #cbdced;
  background: transparent;
  box-shadow: none;
  transform: none;
}

.yizhen-model-tier__index {
  align-self: start;
  margin-top: 26px;
  color: var(--model-ink);
  font-size: 12px;
  font-weight: 720;
  letter-spacing: .14em;
}

.yizhen-model-tier__copy { min-width: 0; }
.yizhen-model-tier__copy h3 {
  display: flex;
  align-items: baseline;
  gap: 18px;
  margin: 0;
  color: #0b2552;
  font-size: clamp(30px, 2.7vw, 40px);
  font-weight: 760;
  line-height: 1.2;
  letter-spacing: -.035em;
}

.yizhen-model-tier__copy h3 span {
  color: var(--model-ink);
  font-size: .57em;
  font-weight: 650;
  letter-spacing: .01em;
}

.yizhen-model-tier__copy > p {
  max-width: 660px;
  margin: 18px 0 17px;
  color: #627995;
  font-size: 14px;
  line-height: 1.8;
}

.yizhen-model-tier__state {
  display: inline-block;
  padding: 6px 11px;
  border: 1px solid #d7e4f1;
  border-radius: 999px;
  color: #55718f;
  font-size: 11px;
  font-weight: 650;
  line-height: 1.2;
}

.yizhen-model-tier__visual {
  --model-shift-x: 0px;
  --model-shift-y: 0px;
  --model-opacity: .62;
  position: relative;
  display: grid;
  place-items: center;
  width: 180px;
  height: 180px;
  justify-self: end;
  margin: 0;
  color: var(--model-ink);
  opacity: var(--model-opacity);
  transition: opacity 350ms ease;
  pointer-events: none;
}

.yizhen-model-tier__visual::before {
  position: absolute;
  inset: 11px;
  border: 1px solid color-mix(in srgb, var(--model-ink) 14%, transparent);
  border-radius: 38px;
  background: radial-gradient(circle at 32% 25%, rgba(255,255,255,.95), var(--model-soft) 78%);
  content: '';
}

.yizhen-model-tier__visual svg {
  position: relative;
  z-index: 1;
  display: block;
  width: 146px;
  height: 146px;
  filter: drop-shadow(0 4px 9px color-mix(in srgb, var(--model-ink) 12%, transparent));
  transform: translate(var(--model-shift-x), var(--model-shift-y));
  transition: transform 360ms cubic-bezier(.22, 1, .36, 1);
}

@media (max-width: 900px) {
  .yizhen-model-tiers { width: calc(100% - 36px); }
  .yizhen-model-tier { grid-template-columns: 38px minmax(0, 1fr) 148px; gap: 20px; min-height: 190px; }
  .yizhen-model-tier__visual { width: 146px; height: 146px; }
  .yizhen-model-tier__visual svg { width: 118px; height: 118px; }
}

@media (max-width: 560px) {
  .yizhen-model-tiers { margin: 62px auto 82px; }
  .yizhen-products-enhanced .detail-hero__copy > .yizhen-model-introduction { font-size: 12px; line-height: 1.72; }
  .yizhen-model-tiers__header { padding-bottom: 27px; }
  .yizhen-model-tiers__header h2 { font-size: 32px; }
  .yizhen-model-tiers__header > p { margin-top: 17px; font-size: 13px; line-height: 1.8; }
  .yizhen-model-tier { grid-template-columns: 26px minmax(0, 1fr) 76px; gap: 10px; min-height: 180px; padding: 25px 0; }
  .yizhen-model-tier__index { margin-top: 5px; font-size: 10px; }
  .yizhen-model-tier__copy h3 { display: block; font-size: 25px; }
  .yizhen-model-tier__copy h3 span { display: block; margin-top: 3px; font-size: 13px; }
  .yizhen-model-tier__copy > p { margin: 12px 0; font-size: 12px; line-height: 1.65; }
  .yizhen-model-tier__state { padding: 5px 8px; font-size: 10px; }
  .yizhen-model-tier__visual { position: relative; top: auto; right: auto; grid-column: 3; width: 76px; height: 76px; align-self: start; }
  .yizhen-model-tier__visual::before { inset: 3px; border-radius: 19px; }
  .yizhen-model-tier__visual svg { width: 67px; height: 67px; }
}

@media (prefers-reduced-motion: reduce) {
  .yizhen-model-tier__visual,
  .yizhen-model-tier__visual svg { transition: none; }
}

@media (max-width: 350px) {
  .yizhen-performance-card__value { font-size: 36px; }
}

/* Product hero: four independent analysis planes */
.yizhen-products-enhanced .yizhen-analysis-stage {
  position: relative;
  width: min(680px, 125%);
  height: 520px;
  justify-self: center;
  margin-left: -45px;
  --parallax-x: 0px;
  --parallax-y: 0px;
  --parallax-rx: 0deg;
  --parallax-ry: 0deg;
}

.analysis-stage__labels {
  position: absolute;
  z-index: 10;
  top: 4px;
  left: 18%;
  right: 1%;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.analysis-stage__labels button {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  min-height: 48px;
  padding: 2px 8px 2px 12px;
  border: 0;
  border-left: 1px solid rgba(51, 140, 228, .4);
  background: transparent;
  color: #173a70;
  text-align: left;
  cursor: pointer;
  transition: border-color 200ms ease, color 200ms ease;
}

.analysis-stage__labels button b {
  display: flex;
  align-items: baseline;
  gap: 9px;
  color: #4898e6;
  font-size: 16px;
  line-height: 1.3;
  letter-spacing: .04em;
  transition: color 200ms ease;
}

.analysis-stage__labels button b strong {
  color: #163d73;
  font-size: 17px;
  font-weight: 760;
  letter-spacing: -.015em;
}

.analysis-stage__labels button span { font-size: 12px; font-weight: 700; white-space: nowrap; }
.analysis-stage__labels button[aria-pressed="true"] { border-color: #0978df; color: #052e61; }
.analysis-stage__labels button[aria-pressed="true"] b { color: #006fe6; }
@media (hover: hover) and (pointer: fine) {
  .analysis-stage__labels button:hover { border-color: #0978df; color: #052e61; }
  .analysis-stage__labels button:hover b { color: #006fe6; }
}
.analysis-stage__labels button:focus-visible,
.analysis-stage__plane button:focus-visible { outline: 2px solid #147ee9; outline-offset: 3px; }

.analysis-stage__stack {
  position: absolute;
  inset: 0;
  transform: translate3d(var(--parallax-x), var(--parallax-y), 0) rotateX(var(--parallax-rx)) rotateY(var(--parallax-ry));
  transform-style: preserve-3d;
  transition: transform 400ms cubic-bezier(.22,.61,.36,1);
}

.analysis-stage__plane {
  position: absolute;
  top: var(--plane-top);
  left: var(--plane-left);
  width: 41%;
  aspect-ratio: .77;
  overflow: hidden;
  border: 1px solid rgba(74, 146, 218, .34);
  border-radius: 5px;
  background: #eaf4ff;
  box-shadow: 0 22px 38px rgba(35, 94, 165, .09), inset 0 0 0 2px rgba(255,255,255,.58);
  opacity: var(--plane-opacity, 1);
  transform: perspective(1400px) rotateY(-8deg) rotateX(1deg) translateZ(var(--plane-z, 0px)) translateX(var(--focus-x, 0px));
  transform-style: preserve-3d;
  transition: transform 220ms cubic-bezier(.22,.61,.36,1), opacity 220ms ease, border-color 220ms ease, filter 220ms ease;
}

.analysis-stage__plane::after {
  position: absolute;
  inset: 0;
  border: 2px solid rgba(255,255,255,.55);
  border-radius: inherit;
  content: '';
  pointer-events: none;
}

.analysis-stage__plane button {
  display: block;
  width: 100%;
  height: 100%;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.analysis-stage__plane--original { --plane-left: 4%; --plane-top: 23%; --plane-z: 54px; z-index: 4; }
.analysis-stage__plane--lens { --plane-left: 21%; --plane-top: 20%; --plane-z: 36px; z-index: 3; }
.analysis-stage__plane--scope { --plane-left: 38%; --plane-top: 17%; --plane-z: 18px; z-index: 2; }
.analysis-stage__plane--spectra { --plane-left: 55%; --plane-top: 14%; --plane-z: 0px; z-index: 1; background: #d8e8f5; }

.analysis-stage__plane--original img,
.analysis-stage__photo {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 51% 50%;
}

.analysis-stage__photo { background: url('/assets/analysis-original-v1.webp') 51% 50% / cover no-repeat; }
.analysis-stage__plane--lens .analysis-stage__photo {
  background-image: url('/assets/analysis-lens-v2.webp');
  opacity: .94;
}
.analysis-stage__lens-grid {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(246,251,255,.16), transparent 44%, rgba(14,102,193,.08));
  opacity: .55;
  transition: opacity 220ms ease;
}

.analysis-stage__plane--scope .analysis-stage__photo {
  background-image: url('/assets/analysis-scope-v2.webp');
  opacity: .95;
}
.analysis-stage__scope-texture {
  position: absolute;
  inset: 0;
  background: linear-gradient(145deg, rgba(239,249,255,.12), transparent 48%, rgba(3,43,115,.12));
  opacity: .45;
  transition: opacity 220ms ease;
}

.analysis-stage__plane--spectra .analysis-stage__photo {
  background-image: url('/assets/analysis-spectra-v2.webp');
  opacity: .98;
}
.analysis-stage__spectra-shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(145deg, rgba(242,249,255,.08), transparent 40%, rgba(4,53,118,.12));
}
.analysis-stage__evidence {
  position: absolute;
  width: 25px;
  height: 25px;
  border: 1.5px solid rgba(60,172,246,.78);
  background: rgba(93,192,255,.13);
  box-shadow: 0 0 0 5px rgba(84,170,239,.08);
  opacity: .48;
  transition: opacity 220ms ease, transform 220ms ease;
}
.analysis-stage__evidence::before,
.analysis-stage__evidence::after {
  position: absolute;
  background: rgba(103,196,255,.86);
  content: '';
}
.analysis-stage__evidence::before { width: 9px; height: 1px; left: 7px; top: 11px; }
.analysis-stage__evidence::after { width: 1px; height: 9px; left: 11px; top: 7px; }
.evidence-a { left: 27%; top: 33%; }
.evidence-b { right: 19%; top: 51%; }
.evidence-c { left: 41%; bottom: 18%; }
.yizhen-analysis-stage.is-ready:not([data-active-stage="spectra"]) .analysis-stage__evidence {
  animation: analysis-evidence-breathe 6s infinite;
  animation-play-state: paused;
}
.yizhen-analysis-stage.is-ready.is-visible:not([data-active-stage="spectra"]) .analysis-stage__evidence { animation-play-state: running; }
.yizhen-analysis-stage .evidence-b { animation-delay: 2s !important; }
.yizhen-analysis-stage .evidence-c { animation-delay: 4s !important; }
@keyframes analysis-evidence-breathe {
  0%, 17%, 100% { opacity: .45; transform: scale(1); }
  8% { opacity: .78; transform: scale(1.07); }
}

.yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--lens { --focus-x: -55px; opacity: 0; }
.yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--scope { --focus-x: -110px; opacity: 0; }
.yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--spectra { --focus-x: -165px; opacity: 0; }
.yizhen-analysis-stage.is-entering .analysis-stage__plane--lens { transition: transform 580ms 120ms cubic-bezier(.22,.61,.36,1), opacity 420ms 120ms ease; }
.yizhen-analysis-stage.is-entering .analysis-stage__plane--scope { transition: transform 580ms 220ms cubic-bezier(.22,.61,.36,1), opacity 420ms 220ms ease; }
.yizhen-analysis-stage.is-entering .analysis-stage__plane--spectra { transition: transform 580ms 320ms cubic-bezier(.22,.61,.36,1), opacity 420ms 320ms ease; }
.yizhen-analysis-stage:not(.is-ready) .analysis-stage__labels { opacity: 0; }
.yizhen-analysis-stage.is-ready .analysis-stage__labels { animation: analysis-label-enter 300ms 500ms both; }
@keyframes analysis-label-enter { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: translateY(0); } }

.yizhen-analysis-stage[data-active-stage] .analysis-stage__plane { opacity: .68; }
.yizhen-analysis-stage[data-active-stage="lens"] .analysis-stage__plane--lens,
.yizhen-analysis-stage[data-active-stage="scope"] .analysis-stage__plane--scope,
.yizhen-analysis-stage[data-active-stage="spectra"] .analysis-stage__plane--spectra {
  --focus-x: 8px;
  opacity: 1;
  border-color: rgba(24,126,223,.68);
  filter: brightness(1.1);
  z-index: 5;
}
.yizhen-analysis-stage[data-active-stage="scope"] .analysis-stage__scope-texture { opacity: .58; }
.yizhen-analysis-stage[data-active-stage="lens"] .analysis-stage__lens-grid { opacity: .7; }
.yizhen-analysis-stage[data-active-stage="spectra"] .analysis-stage__evidence { opacity: .8; transform: scale(1.07); }

.analysis-stage__microcopy {
  position: absolute;
  bottom: 1px;
  left: 18%;
  right: 0;
  min-height: 22px;
  margin: 0;
  color: #426d9b;
  font-size: 12px;
  text-align: center;
  pointer-events: none;
}
.analysis-stage__microcopy span { position: absolute; inset: 0; opacity: 0; transform: translateY(4px); transition: opacity 200ms ease, transform 200ms ease; }
.yizhen-analysis-stage[data-active-stage="lens"] .analysis-stage__microcopy [data-copy="lens"],
.yizhen-analysis-stage[data-active-stage="scope"] .analysis-stage__microcopy [data-copy="scope"],
.yizhen-analysis-stage[data-active-stage="spectra"] .analysis-stage__microcopy [data-copy="spectra"] { opacity: 1; transform: translateY(0); }

@media (max-width: 1199px) {
  .yizhen-products-enhanced .yizhen-analysis-stage { width: min(600px, 100%); height: 470px; margin-left: 0; }
  .analysis-stage__plane { width: 41%; }
}
@media (max-width: 900px) {
  .yizhen-products-enhanced .yizhen-analysis-stage { width: min(600px, 100%); margin: 10px auto 0; }
}
@media (max-width: 600px) {
  .yizhen-products-enhanced .yizhen-analysis-stage { width: 100%; height: max(310px, 78vw); margin: 12px auto 0; }
  .analysis-stage__labels { top: 0; left: 1%; right: 0; gap: 3px; }
  .analysis-stage__labels button { min-height: 44px; padding-left: 7px; }
  .analysis-stage__labels button b { gap: 5px; font-size: 12px; }
  .analysis-stage__labels button b strong { font-size: 13px; }
  .analysis-stage__labels button span { font-size: 10px; }
  .analysis-stage__plane { top: calc(var(--plane-top) + 24px); width: 43%; }
  .analysis-stage__microcopy { bottom: 0; left: 0; font-size: 11px; }
}
@media (max-width: 767px) {
  .yizhen-products-enhanced .analysis-stage__evidence { animation: none !important; }
  .yizhen-products-enhanced .analysis-stage__stack { transform: none !important; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-products-enhanced .yizhen-analysis-stage *,
  .yizhen-products-enhanced .yizhen-analysis-stage *::before,
  .yizhen-products-enhanced .yizhen-analysis-stage *::after { animation: none !important; transition: none !important; }
  .yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--lens,
  .yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--scope,
  .yizhen-analysis-stage:not(.is-ready) .analysis-stage__plane--spectra { --focus-x: 0px; opacity: 1; }
  .yizhen-analysis-stage:not(.is-ready) .analysis-stage__labels { opacity: 1; }
}

/* Quiet product-page response and one-time reveal */
.yizhen-products-enhanced .detail-hero__copy > p:first-child { animation: product-copy-enter 360ms cubic-bezier(.22,.61,.36,1) both; }
.yizhen-products-enhanced .yizhen-product-hero-title { animation: product-title-enter 420ms 80ms cubic-bezier(.22,.61,.36,1) both; }
.yizhen-products-enhanced .yizhen-product-hero-wave { animation: product-wave-draw 450ms 160ms cubic-bezier(.22,.61,.36,1) both; }
.yizhen-products-enhanced .yizhen-model-introduction { animation: product-copy-enter 320ms 160ms cubic-bezier(.22,.61,.36,1) both; }
.yizhen-products-enhanced .detail-hero__actions { animation: product-actions-enter 260ms 240ms ease both; }
@keyframes product-title-enter { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
@keyframes product-copy-enter { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: translateY(0); } }
@keyframes product-actions-enter { from { opacity: 0; } to { opacity: 1; } }
@keyframes product-wave-draw { from { opacity: 0; clip-path: inset(0 50% 0 50%); } to { opacity: 1; clip-path: inset(0 0 0 0); } }

.yizhen-products-enhanced .detail-hero__actions a:first-child { transition: filter 200ms ease, border-color 200ms ease; }
.yizhen-products-enhanced .detail-hero__actions a:first-child span { display: inline-block; transition: transform 200ms cubic-bezier(.22,.61,.36,1); }
.yizhen-products-enhanced .detail-hero__actions a:first-child:hover { filter: brightness(1.04); }
.yizhen-products-enhanced .detail-hero__actions a:first-child:hover span { transform: translateX(4px); }
.yizhen-products-enhanced .detail-hero__actions a:nth-child(2) { transition: background-color 200ms ease, border-color 200ms ease, color 200ms ease; }
.yizhen-products-enhanced .detail-hero__actions a:nth-child(2):hover { background: #f0f7ff; border-color: #a6c8ed; color: #164e8b; }

.yizhen-products-enhanced .detail-facts > div { position: relative; }
.yizhen-products-enhanced .detail-facts > div::before { position: absolute; top: 0; left: 20px; width: 28px; height: 2px; background: #2285ec; content: ''; transform: scaleX(0); transform-origin: left; transition: transform 200ms ease; }
.yizhen-products-enhanced .detail-facts > div:hover::before { transform: scaleX(1); }
.yizhen-products-enhanced .detail-facts dd { transition: transform 200ms ease, color 200ms ease; }
.yizhen-products-enhanced .detail-facts > div:hover dd { transform: translateY(-2px); color: #073877; }

.yizhen-products-enhanced .app-header { transition: height 220ms ease, background-color 220ms ease, border-color 220ms ease, box-shadow 220ms ease; }
.yizhen-products-enhanced .app-header.is-scrolled { height: 71px; background: rgba(249,252,255,.88); border-color: rgba(111,153,201,.28); box-shadow: 0 7px 24px rgba(28,70,120,.08); backdrop-filter: saturate(145%) blur(21px); }

@media (prefers-reduced-motion: reduce) {
  .yizhen-products-enhanced .detail-hero__copy > p:first-child,
  .yizhen-products-enhanced .yizhen-product-hero-title,
  .yizhen-products-enhanced .yizhen-product-hero-wave,
  .yizhen-products-enhanced .yizhen-model-introduction,
  .yizhen-products-enhanced .detail-hero__actions { animation: none !important; }
  .yizhen-products-enhanced .detail-hero__actions a,
  .yizhen-products-enhanced .detail-hero__actions a span,
  .yizhen-products-enhanced .detail-facts dd,
  .yizhen-products-enhanced .detail-facts > div::before,
  .yizhen-products-enhanced .app-header { transition: none !important; }
}

/* Three model cards. Scoped to the products model section. */
.yizhen-model-tiers { width: min(1240px, calc(100% - 72px)); margin: 80px auto 112px; }
.yizhen-model-tiers__header { padding: 0 0 28px; border-bottom: 0; }
.yizhen-model-tiers__header h2 { font-size: clamp(32px, 3.1vw, 46px); }
.yizhen-model-tiers__list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}
.yizhen-model-tier,
.yizhen-model-tier:hover {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0;
  min-width: 0;
  min-height: 510px;
  padding: 0;
  overflow: hidden;
  border: 1px solid #dce8f5;
  border-radius: 22px;
  background: #f9fcff;
  box-shadow: 0 16px 44px rgba(22, 63, 114, .055);
  transform: none;
}
.yizhen-model-tier:hover { border-color: #b9d6ef; box-shadow: 0 20px 50px rgba(22, 63, 114, .09); }
.yizhen-model-tier__visual {
  --model-x: 50%;
  --model-y: 50%;
  --model-tilt-x: 0deg;
  --model-tilt-y: 0deg;
  position: relative;
  display: grid;
  place-items: center;
  flex: none;
  width: 100%;
  height: 242px;
  margin: 0;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 60%, rgba(45, 104, 180, .28), transparent 58%),
    linear-gradient(140deg, #091c3b, #0a2449 54%, #071a35);
  opacity: 1;
  isolation: isolate;
  pointer-events: auto;
}
.yizhen-model-tier.is-scope .yizhen-model-tier__visual {
  background: radial-gradient(circle at 50% 60%, rgba(73, 99, 197, .27), transparent 58%), linear-gradient(140deg, #0b1b3b, #142b58 54%, #091a36);
}
.yizhen-model-tier.is-spectra .yizhen-model-tier__visual {
  background: radial-gradient(circle at 50% 60%, rgba(138, 77, 98, .17), transparent 58%), linear-gradient(140deg, #111c3a, #172746 54%, #0a1933);
}
.yizhen-model-tier__visual::before {
  position: absolute;
  z-index: 1;
  inset: 0;
  border: 0;
  border-radius: 0;
  background: radial-gradient(circle 220px at var(--model-x) var(--model-y), rgba(112, 190, 255, .16), transparent 75%);
  opacity: 0;
  transition: opacity 220ms ease;
  pointer-events: none;
  content: '';
}
.yizhen-model-tier__visual::after {
  position: absolute;
  inset: 0;
  border-radius: 0;
  background: linear-gradient(180deg, rgba(255,255,255,.025), transparent 45%, rgba(0,0,0,.13));
  pointer-events: none;
  content: '';
}
.yizhen-model-tiers .yizhen-model-tier__visual img {
  display: block;
  width: min(270px, 82%);
  height: 238px;
  object-fit: contain;
  opacity: 1;
  filter: drop-shadow(0 13px 25px rgba(31, 147, 255, .12));
  transform: perspective(700px) rotateX(var(--model-tilt-x)) rotateY(var(--model-tilt-y));
  transition: transform 300ms ease;
}
.yizhen-model-tiers .yizhen-model-tier:hover .yizhen-model-tier__visual img {
  opacity: 1;
  filter: drop-shadow(0 13px 25px rgba(31, 147, 255, .12));
  transform: perspective(700px) rotateX(var(--model-tilt-x)) rotateY(var(--model-tilt-y));
}
.yizhen-model-tier.is-spectra .yizhen-model-tier__visual img { width: min(264px, 80%); }
@media (hover: hover) and (pointer: fine) {
  .yizhen-model-tier__visual:hover::before { opacity: 1; }
}
.yizhen-model-tier__copy {
  display: flex;
  flex: 1;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
  padding: 27px 28px 26px;
}
.yizhen-model-tier__index {
  align-self: auto;
  margin: 0 0 12px;
  color: #5198d5;
  font-size: 11px;
  line-height: 1.2;
}
.yizhen-model-tier__copy h3 {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  font-size: clamp(27px, 2.5vw, 35px);
  line-height: 1.28;
}
.yizhen-model-tier__copy h3 span { font-size: 15px; color: #436b98; letter-spacing: .02em; }
.yizhen-model-tier__copy > p {
  max-width: none;
  min-height: 56px;
  margin: 16px 0 18px;
  color: #637c99;
  font-size: 14px;
  line-height: 1.75;
}
.yizhen-model-tier__state {
  margin-top: auto;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
  color: #6581a0;
  font-size: 12px;
  line-height: 1.5;
}
.yizhen-model-tier__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 126px;
  min-height: 44px;
  margin-top: 12px;
  padding: 0 20px;
  border-radius: 12px;
  background: linear-gradient(100deg, #0877db, #169de9);
  box-shadow: 0 8px 20px rgba(20, 128, 222, .16);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}
.yizhen-model-tier__link:hover { color: #fff; background: #086dcd; }
.yizhen-model-tier__link:focus-visible,
.yizhen-model-tiers__list:focus-visible { outline: 3px solid #2d84ef; outline-offset: 3px; }
.yizhen-model-tier:not(.is-lens) .yizhen-model-tier__state { margin-top: auto; }
.yizhen-model-tiers:not(.is-revealed) .yizhen-model-tier { opacity: 0; transform: translateY(14px); }
.yizhen-model-tiers.is-revealed .yizhen-model-tier { opacity: 1; transform: none; transition: opacity 430ms ease, transform 430ms ease, border-color 220ms ease, box-shadow 220ms ease; }
.yizhen-model-tiers.is-revealed .yizhen-model-tier:nth-child(2) { transition-delay: 80ms; }
.yizhen-model-tiers.is-revealed .yizhen-model-tier:nth-child(3) { transition-delay: 160ms; }
@media (max-width: 1119px) {
  .yizhen-model-tiers__list {
    display: flex;
    gap: 18px;
    overflow-x: auto;
    overflow-y: hidden;
    padding: 2px 0 20px;
    scroll-snap-type: x mandatory;
    scroll-padding-inline: 0;
    scrollbar-width: thin;
    overscroll-behavior-inline: contain;
    -webkit-overflow-scrolling: touch;
  }
  .yizhen-model-tier, .yizhen-model-tier:hover { flex: 0 0 min(390px, 47vw); min-height: 502px; scroll-snap-align: start; }
}
@media (max-width: 767px) {
  .yizhen-model-tiers { width: calc(100% - 36px); margin: 62px auto 82px; }
  .yizhen-model-tiers__header { padding-bottom: 22px; }
  .yizhen-model-tiers__header h2 { font-size: clamp(29px, 7vw, 36px); }
  .yizhen-model-tiers__list { width: calc(100% + 18px); gap: 14px; }
  .yizhen-model-tier, .yizhen-model-tier:hover { flex-basis: 82.4vw; min-height: 490px; }
  .yizhen-model-tier__visual { width: 100%; height: 224px; }
  .yizhen-model-tiers .yizhen-model-tier__visual img { height: 220px; width: min(248px, 82%); }
  .yizhen-model-tier__copy { padding: 23px 22px 24px; }
  .yizhen-model-tier__copy h3 { display: flex; font-size: 30px; }
  .yizhen-model-tier__copy h3 span { display: inline; margin-top: 0; font-size: 14px; }
  .yizhen-model-tier__copy > p { min-height: 55px; margin: 14px 0 17px; font-size: 13px; line-height: 1.72; }
  .yizhen-model-tier__state { padding: 0; font-size: 11px; }
}
@media (prefers-reduced-motion: reduce), (hover: none) {
  .yizhen-model-tiers:not(.is-revealed) .yizhen-model-tier { opacity: 1; transform: none; }
  .yizhen-model-tier__visual::before { display: none; }
  .yizhen-model-tier__visual img { transform: none; transition: none; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-model-tiers.is-revealed .yizhen-model-tier { transition: none; }
}

/* Integrated model artwork: the icon becomes part of each card's atmosphere. */
.yizhen-products-enhanced .detail-page { overflow-x: clip; overflow-y: visible; }
.yizhen-model-tiers { scroll-margin-top: 110px; }
.yizhen-model-tier,
.yizhen-model-tier:hover {
  position: relative;
  min-height: 490px;
  background:
    radial-gradient(circle at 84% 55%, rgba(102, 177, 245, .13), transparent 52%),
    linear-gradient(145deg, #fff 4%, #f5faff 100%);
}
.yizhen-model-tier.is-scope,
.yizhen-model-tier.is-scope:hover {
  background: radial-gradient(circle at 84% 55%, rgba(104, 130, 229, .13), transparent 52%), linear-gradient(145deg, #fff 4%, #f7f9ff 100%);
}
.yizhen-model-tier.is-spectra,
.yizhen-model-tier.is-spectra:hover {
  background: radial-gradient(circle at 84% 55%, rgba(168, 128, 216, .12), transparent 52%), linear-gradient(145deg, #fff 4%, #faf8ff 100%);
}
.yizhen-model-tier__visual,
.yizhen-model-tier.is-scope .yizhen-model-tier__visual,
.yizhen-model-tier.is-spectra .yizhen-model-tier__visual {
  position: absolute;
  z-index: 0;
  inset: 0;
  width: 100%;
  height: 100%;
  background: transparent;
  isolation: auto;
}
.yizhen-model-tier__visual::before {
  z-index: 2;
  background: radial-gradient(circle 230px at var(--model-x) var(--model-y), rgba(135, 194, 247, .17), transparent 75%);
}
.yizhen-model-tier__visual::after {
  z-index: 1;
  background: linear-gradient(90deg, rgba(255,255,255,.72), rgba(255,255,255,.15) 60%, transparent 100%);
}
.yizhen-model-tiers .yizhen-model-tier__visual img,
.yizhen-model-tiers .yizhen-model-tier.is-spectra .yizhen-model-tier__visual img,
.yizhen-model-tiers .yizhen-model-tier:hover .yizhen-model-tier__visual img {
  position: absolute;
  right: -24%;
  top: 2%;
  width: 128%;
  height: 95%;
  object-fit: contain;
  opacity: .22;
  filter: saturate(.72) drop-shadow(0 20px 40px rgba(50, 105, 172, .05));
  transform: perspective(700px) rotateX(var(--model-tilt-x)) rotateY(var(--model-tilt-y));
}
.yizhen-model-tier__copy {
  position: relative;
  z-index: 3;
  min-height: 490px;
  padding: 36px 33px 32px;
  pointer-events: none;
}
.yizhen-model-tier__link { pointer-events: auto; }
.yizhen-model-tier__index { margin-bottom: 25px; }
.yizhen-model-tier__copy h3 { display: block; font-size: clamp(32px, 2.7vw, 39px); }
.yizhen-model-tier__copy h3 span { display: block; margin-top: 7px; font-size: 15px; }
.yizhen-model-tier__copy > p { max-width: 290px; margin-top: 25px; font-size: 14px; color: #516e91; }
.yizhen-model-tier__state { color: #526f91; }
@media (max-width: 1119px) {
  .yizhen-model-tier, .yizhen-model-tier:hover { min-height: 490px; }
}
@media (max-width: 767px) {
  .yizhen-model-tier, .yizhen-model-tier:hover { min-height: 450px; }
  .yizhen-model-tier__copy { min-height: 450px; padding: 29px 24px 25px; }
  .yizhen-model-tier__index { margin-bottom: 20px; }
  .yizhen-model-tier__copy h3 { display: block; font-size: 31px; }
  .yizhen-model-tier__copy h3 span { display: block; margin-top: 5px; font-size: 13px; }
  .yizhen-model-tier__copy > p { margin-top: 21px; font-size: 13px; }
}
@media (prefers-reduced-motion: reduce), (hover: none) {
  .yizhen-model-tiers .yizhen-model-tier__visual img,
  .yizhen-model-tiers .yizhen-model-tier:hover .yizhen-model-tier__visual img { transform: none; }
}

/* V2 copy within the previous integrated card design. */
.yizhen-model-tiers__header { padding-bottom: 30px; }
.yizhen-model-tiers__header div > p:first-child { color: #426fa5; }
.yizhen-model-tiers__header .yizhen-model-tiers__subtitle {
  max-width: 840px;
  margin: 12px 0 0;
  color: #5b7290;
  font-size: 15px;
  font-weight: 400;
  line-height: 1.7;
  letter-spacing: 0;
}
.yizhen-model-tier__index { color: #3a75b3; }
.yizhen-model-tier__copy > p { color: #395274; }
.yizhen-model-tier__link,
.yizhen-model-tiers .yizhen-model-tier__link { background: #086dcd; color: #fff; }
.yizhen-model-tier__link:hover,
.yizhen-model-tiers .yizhen-model-tier__link:hover { background: #075fb4; color: #fff; }
.yizhen-model-tiers .yizhen-model-tier__visual::before { display: none; }
.yizhen-model-tiers.is-revealed .yizhen-model-tier {
  transition: transform 240ms ease, border-color 240ms ease, box-shadow 240ms ease;
}
.yizhen-model-tiers.is-revealed .yizhen-model-tier:nth-child(2),
.yizhen-model-tiers.is-revealed .yizhen-model-tier:nth-child(3) { transition-delay: 0ms; }
.yizhen-model-tiers .yizhen-model-tier__visual img { transition: transform 240ms ease; }
.yizhen-model-tiers .yizhen-model-tier:not(.is-lens) .yizhen-model-tier__copy::after {
  display: block;
  flex: 0 0 44px;
  width: 1px;
  margin-top: 12px;
  content: '';
}
@media (hover: hover) and (pointer: fine) {
  .yizhen-model-tiers.is-revealed .yizhen-model-tier:hover { transform: translateY(-3px); }
  .yizhen-model-tiers .yizhen-model-tier:hover .yizhen-model-tier__visual img { transform: scale(1.015); }
}
@media (min-width: 768px) and (max-width: 1199px) {
  .yizhen-model-tiers__list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; overflow: visible; padding: 0; }
  .yizhen-model-tiers .yizhen-model-tier,
  .yizhen-model-tiers .yizhen-model-tier:hover { min-height: 500px; }
  .yizhen-model-tiers .yizhen-model-tier__copy { min-height: 500px; padding: 30px 20px 26px; }
  .yizhen-model-tiers .yizhen-model-tier__copy h3 { font-size: clamp(27px, 2.8vw, 32px); }
  .yizhen-model-tiers .yizhen-model-tier__copy > p { font-size: 13px; }
}
@media (max-width: 767px) {
  .yizhen-model-tiers__header .yizhen-model-tiers__subtitle { margin-top: 10px; font-size: 13px; line-height: 1.65; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-model-tiers.is-revealed .yizhen-model-tier,
  .yizhen-model-tiers .yizhen-model-tier__visual img { transition: none; }
  .yizhen-model-tiers.is-revealed .yizhen-model-tier:hover,
  .yizhen-model-tiers .yizhen-model-tier:hover .yizhen-model-tier__visual img { transform: none; }
}
.yizhen-model-tiers .yizhen-model-tier__copy > p { color: #395274; }

/* A second copy of the artwork is revealed only around the pointer. */
.yizhen-model-tier__reveal-window {
  position: absolute;
  inset: 0;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to bottom, transparent 230px, rgba(0,0,0,.72) 270px, #000 292px, #000 326px, transparent 378px);
  mask-image: linear-gradient(to bottom, transparent 230px, rgba(0,0,0,.72) 270px, #000 292px, #000 326px, transparent 378px);
}
.yizhen-model-tiers .yizhen-model-tier .yizhen-model-tier__visual img.yizhen-model-tier__reveal {
  opacity: 0;
  filter: saturate(.95) drop-shadow(0 18px 34px rgba(45, 104, 176, .08));
  -webkit-mask-image: radial-gradient(ellipse 142px 162px at var(--reveal-x, 50%) var(--reveal-y, 50%), #000 8%, rgba(0,0,0,.82) 36%, rgba(0,0,0,.32) 69%, transparent 100%);
  mask-image: radial-gradient(ellipse 142px 162px at var(--reveal-x, 50%) var(--reveal-y, 50%), #000 8%, rgba(0,0,0,.82) 36%, rgba(0,0,0,.32) 69%, transparent 100%);
  pointer-events: none;
  transition: opacity 260ms ease, transform 240ms ease;
}
@media (hover: hover) and (pointer: fine) {
  .yizhen-model-tiers .yizhen-model-tier.is-interacting .yizhen-model-tier__visual img.yizhen-model-tier__reveal {
    opacity: .74;
  }
}
@media (prefers-reduced-motion: reduce), (hover: none) {
  .yizhen-model-tiers .yizhen-model-tier .yizhen-model-tier__visual img.yizhen-model-tier__reveal {
    display: none;
  }
}
/* Full-height, pointer-local artwork reveal and card typography alignment. */
.yizhen-model-tier__reveal-window {
  z-index: 1;
  -webkit-mask-image: none;
  mask-image: none;
}
.yizhen-model-tier__visual::after {
  z-index: 2;
  background: linear-gradient(90deg, rgba(255,255,255,.98) 0%, rgba(255,255,255,.88) 34%, rgba(255,255,255,.48) 65%, rgba(255,255,255,.04) 100%);
}
.yizhen-model-tiers .yizhen-model-tier__visual::before {
  display: block;
  z-index: 3;
  background: linear-gradient(180deg, rgba(255,255,255,.32) 0%, rgba(255,255,255,.13) 40%, transparent 64%, rgba(255,255,255,.16) 100%);
}
.yizhen-model-tier__copy h3 {
  color: #0a2049;
  font-size: clamp(32px, 2.4vw, 35px);
  font-weight: 700;
  line-height: 1.18;
  letter-spacing: -.035em;
}
.yizhen-model-tier__copy h3 span {
  margin-top: 8px;
  color: #5b7290;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .01em;
}
.yizhen-model-tiers .yizhen-model-tier__copy > p {
  max-width: 250px;
  margin-top: 23px;
  color: #2b4160;
  font-size: 14.5px;
  line-height: 1.7;
}
.yizhen-model-tier__state {
  color: #506b8d;
  font-size: 12.5px;
  font-weight: 600;
  line-height: 1.55;
}
.yizhen-model-tier__index { color: #2b76bf; }
@media (min-width: 768px) and (max-width: 1199px) {
  .yizhen-model-tiers .yizhen-model-tier__copy h3 { font-size: clamp(28px, 2.6vw, 32px); }
  .yizhen-model-tiers .yizhen-model-tier__copy > p { font-size: 14px; }
}
@media (max-width: 767px) {
  .yizhen-model-tier__copy h3 { font-size: 30px; }
  .yizhen-model-tier__copy h3 span { font-size: 14px; }
  .yizhen-model-tiers .yizhen-model-tier__copy > p { margin-top: 20px; font-size: 14px; }
}
/* Product page rails and section rhythm. Keep the status note as an inset. */
@media (min-width: 1200px) {
  .yizhen-products-enhanced .detail-hero,
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers,
  .yizhen-products-enhanced .yizhen-products-performance,
  .yizhen-products-enhanced .detail-next,
  .yizhen-products-enhanced .site-footer {
    width: min(1440px, calc(100% - 72px));
  }

  .yizhen-products-enhanced .detail-notice {
    width: min(1364px, calc(100% - 148px));
  }
}

.yizhen-products-enhanced .detail-content.yizhen-model-tiers {
  margin-top: 72px;
  margin-bottom: 126px;
}

.yizhen-products-enhanced .yizhen-products-performance {
  margin-bottom: 88px;
}

.yizhen-products-enhanced .detail-notice {
  margin-bottom: 76px;
}

@media (min-width: 768px) and (max-width: 900px) {
  .yizhen-products-enhanced .detail-hero {
    width: calc(100% - 36px);
  }
}

@media (max-width: 767px) {
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers {
    margin-top: 62px;
    margin-bottom: 100px;
  }

  .yizhen-products-enhanced .yizhen-products-performance {
    margin-bottom: 72px;
  }

  .yizhen-products-enhanced .detail-notice {
    margin-bottom: 68px;
  }
}
/* Give hero stage labels enough room at narrow desktop widths. */
@media (min-width: 901px) and (max-width: 1100px) {
  .yizhen-products-enhanced .analysis-stage__labels {
    left: 8%;
    gap: 8px;
  }

  .yizhen-products-enhanced .analysis-stage__labels button {
    padding-left: 8px;
  }
}

/* A compact visual seam between the hero and the three levels. */
.yizhen-products-enhanced .detail-hero { min-height: 0; }
.yizhen-particle-bridge {
  position: relative;
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(8px, 1.35vw, 20px);
  height: 38px;
  margin: 24px 0 0;
  overflow: hidden;
}
.yizhen-particle-bridge::before,
.yizhen-particle-bridge::after {
  width: min(27%, 320px);
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(70, 143, 222, .2));
  content: '';
}
.yizhen-particle-bridge::after { transform: rotate(180deg); }
.yizhen-particle-bridge i {
  flex: 0 0 auto;
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: #6ba9e6;
  opacity: .42;
  box-shadow: 0 0 8px rgba(34, 139, 236, .24);
}
.yizhen-particle-bridge i:nth-child(5n + 1) { width: 2px; height: 2px; transform: translateY(-5px); }
.yizhen-particle-bridge i:nth-child(7n + 2) { width: 4px; height: 4px; transform: translateY(4px); }
.yizhen-particle-bridge i:nth-child(3n + 1) { opacity: .24; }
.yizhen-particle-bridge i:nth-child(4n + 2) { opacity: .62; }
.yizhen-products-enhanced .detail-content.yizhen-model-tiers { margin-top: 28px; }
.yizhen-model-tiers__header { margin-bottom: 26px; }
.yizhen-model-tiers__header h2 { letter-spacing: -.035em; }

/* Questions lead; definitions and descriptions follow the page's type scale. */
.yizhen-model-tier__copy .yizhen-model-tier__question {
  min-height: 0;
  max-width: 300px;
  margin: 22px 0 0;
  color: #102b55;
  font-size: clamp(17px, 1.45vw, 20px);
  font-weight: 650;
  line-height: 1.45;
  letter-spacing: -.025em;
}
.yizhen-model-tiers .yizhen-model-tier__copy > p:not(.yizhen-model-tier__question) {
  max-width: 290px;
  min-height: 0;
  margin: 10px 0 20px;
  color: #526f91;
  font-size: 14px;
  line-height: 1.65;
}
.yizhen-model-tier__apply {
  position: relative;
  z-index: 5;
  min-height: 44px;
  margin-top: 12px;
  padding: 0 19px;
  border: 1px solid #abc8e5;
  border-radius: 12px;
  background: rgba(255,255,255,.78);
  color: #15548c;
  font: inherit;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  pointer-events: auto;
  transition: border-color 220ms ease, background-color 220ms ease, transform 220ms ease;
}
.yizhen-model-tier__apply:hover { border-color: #4d95d8; background: #fff; transform: translateY(-2px); }
.yizhen-model-tier__apply:focus-visible { outline: 3px solid #2d84ef; outline-offset: 3px; }
.yizhen-model-tier__copy { padding-bottom: 28px; }
.yizhen-model-tier__state { margin-top: auto; }

body.yizhen-beta-open { overflow: hidden; }
.yizhen-beta-layer { position: fixed; z-index: 9999; inset: 0; font-family: inherit; }
.yizhen-beta-layer__scrim { position: absolute; inset: 0; background: rgba(9, 28, 55, .32); backdrop-filter: blur(3px); }
.yizhen-beta-drawer {
  position: absolute;
  inset: 0 0 0 auto;
  display: flex;
  flex-direction: column;
  width: min(34vw, 560px);
  min-width: 420px;
  overflow-y: auto;
  background: #f8fbff;
  box-shadow: -24px 0 70px rgba(9, 41, 81, .13);
  color: #102b55;
  animation: yizhen-drawer-in 260ms cubic-bezier(.2,.8,.2,1) both;
}
@keyframes yizhen-drawer-in { from { transform: translateX(24px); opacity: .8; } to { transform: none; opacity: 1; } }
.yizhen-beta-drawer__header { position: relative; padding: 40px 38px 26px; border-bottom: 1px solid #dbe8f5; }
.yizhen-beta-drawer__eyebrow { color: #2a79c8; font-size: 11px; font-weight: 800; letter-spacing: .18em; }
.yizhen-beta-drawer__header h2 { margin: 12px 0 8px; font-size: 32px; line-height: 1.2; letter-spacing: -.035em; }
.yizhen-beta-drawer__header p { max-width: 340px; margin: 0; color: #5d7593; font-size: 14px; line-height: 1.65; }
.yizhen-beta-drawer__close { position: absolute; top: 24px; right: 27px; width: 38px; height: 38px; border: 1px solid #d7e7f7; border-radius: 50%; background: #fff; color: #315a83; font-size: 26px; line-height: 1; cursor: pointer; }
.yizhen-beta-form { display: grid; gap: 19px; padding: 27px 38px 40px; }
.yizhen-beta-form__model { margin: 0 0 2px; color: #5c7596; font-size: 13px; }
.yizhen-beta-form__model strong { margin-left: 8px; color: #0f5594; font-size: 15px; }
.yizhen-beta-form fieldset { display: flex; gap: 18px; margin: 0; padding: 0; border: 0; }
.yizhen-beta-form legend { width: 100%; margin-bottom: 11px; color: #233d62; font-size: 13px; font-weight: 650; }
.yizhen-beta-form fieldset label { display: flex; align-items: center; gap: 7px; color: #456485; font-size: 14px; cursor: pointer; }
.yizhen-beta-form input[type="radio"] { accent-color: #0877db; }
.yizhen-beta-form > label,
.yizhen-beta-form__row > label { display: grid; gap: 8px; min-width: 0; color: #233d62; font-size: 13px; font-weight: 650; }
.yizhen-beta-form [hidden] { display: none !important; }
.yizhen-beta-form input:not([type="radio"]),
.yizhen-beta-form select,
.yizhen-beta-form textarea { width: 100%; min-width: 0; min-height: 44px; padding: 10px 12px; border: 1px solid #cfdeee; border-radius: 10px; outline: 0; background: #fff; color: #102b55; font: inherit; font-size: 14px; font-weight: 400; }
.yizhen-beta-form textarea { resize: vertical; }
.yizhen-beta-form input:focus,
.yizhen-beta-form select:focus,
.yizhen-beta-form textarea:focus { border-color: #2183d6; box-shadow: 0 0 0 3px rgba(33, 131, 214, .12); }
.yizhen-beta-form__row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.yizhen-beta-form__footer { padding-top: 4px; }
.yizhen-beta-form__notice { margin: 0 0 14px; color: #5d7593; font-size: 12px; line-height: 1.6; }
.yizhen-beta-form__submit { width: 100%; min-height: 48px; border: 0; border-radius: 12px; background: #0877db; color: #fff; font: inherit; font-size: 14px; font-weight: 700; cursor: pointer; }
.yizhen-beta-form__submit:disabled { background: #dce9f5; color: #6885a2; cursor: not-allowed; }
.yizhen-beta-drawer__close:focus-visible,
.yizhen-beta-form__submit:focus-visible { outline: 3px solid #2d84ef; outline-offset: 3px; }
@media (max-width: 767px) {
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers { margin-top: 20px; }
  .yizhen-particle-bridge { height: 28px; margin-top: 14px; gap: 8px; }
  .yizhen-particle-bridge i:nth-of-type(n+15) { display: none; }
  .yizhen-model-tier__copy .yizhen-model-tier__question { margin-top: 18px; font-size: 17px; }
  .yizhen-model-tiers .yizhen-model-tier__copy > p:not(.yizhen-model-tier__question) { margin-top: 8px; font-size: 13px; }
  .yizhen-beta-drawer { width: min(100%, 440px); min-width: 0; }
  .yizhen-beta-drawer__header { padding: 30px 24px 22px; }
  .yizhen-beta-form { padding: 24px 24px 36px; }
}
@media (max-width: 390px) { .yizhen-beta-form__row { grid-template-columns: 1fr; } }
@media (prefers-reduced-motion: reduce) { .yizhen-beta-drawer { animation: none; } .yizhen-model-tier__apply { transition: none; } }

/* Product hero owns the first viewport; the next chapter starts after it. */
@media (min-width: 901px) {
  .yizhen-products-enhanced .detail-hero {
    min-height: calc(100vh - 96px);
    min-height: calc(100svh - 96px);
  }
}

/* A sparse field of signal points makes the chapter transition visible. */
.yizhen-particle-bridge { overflow: visible; }
.yizhen-particle-bridge::before,
.yizhen-particle-bridge::after { width: min(20%, 220px); }
.yizhen-particle-bridge i { --scatter-y: 0px; transform: translate3d(0, var(--scatter-y), 0); }
.yizhen-particle-bridge i:nth-child(4n + 1) { --scatter-y: -26px; }
.yizhen-particle-bridge i:nth-child(5n + 2) { --scatter-y: -60px; }
.yizhen-particle-bridge i:nth-child(7n + 3) { --scatter-y: -92px; }
.yizhen-particle-bridge i:nth-child(11n + 4) { --scatter-y: -132px; }
.yizhen-particle-bridge i:nth-child(3n + 1) { animation: yizhen-signal-drift 7s ease-in-out infinite alternate; }
.yizhen-particle-bridge i:nth-child(4n + 2) { animation: yizhen-signal-drift 9s ease-in-out 1.4s infinite alternate-reverse; }
@keyframes yizhen-signal-drift {
  from { transform: translate3d(0, var(--scatter-y), 0); opacity: .2; }
  to { transform: translate3d(7px, calc(var(--scatter-y) - 10px), 0); opacity: .58; }
}

/* The second chapter uses the same navy-to-blue hierarchy as the hero. */
.yizhen-model-tiers__header { margin-bottom: 32px; }
.yizhen-model-tiers__header h2 {
  max-width: 760px;
  color: #0a2049;
  font-size: clamp(40px, 3.6vw, 54px);
  font-weight: 800;
  line-height: 1.16;
  letter-spacing: -.045em;
  padding-block: .04em .08em;
}
.yizhen-model-tiers__header h2 span,
.yizhen-model-tiers__header h2 strong { display: block; font: inherit; }
.yizhen-model-tiers__header h2 strong {
  color: #0a73e8;
  background: linear-gradient(98deg, #096fe4 4%, #18a8ef 48%, #7651e9 96%);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.yizhen-model-tiers__header .yizhen-model-tiers__subtitle {
  margin-top: 16px;
  color: #617b9b;
  font-size: 16px;
  line-height: 1.7;
}
.yizhen-model-tier__copy h3 { color: #0a2049; }
.yizhen-model-tier__copy h3 span { color: #5a7696; }
.yizhen-model-tier__copy .yizhen-model-tier__question { color: #173b6c; }
.yizhen-model-tiers .yizhen-model-tier__copy > p:not(.yizhen-model-tier__question) { color: #5b7593; }

@media (max-width: 767px) {
  .yizhen-particle-bridge i { --scatter-y: 0px !important; }
  .yizhen-particle-bridge i:nth-child(3n + 1) { --scatter-y: -12px !important; }
  .yizhen-particle-bridge i:nth-child(4n + 2) { --scatter-y: -24px !important; }
  .yizhen-model-tiers__header h2 { font-size: clamp(29px, 7vw, 36px); }
  .yizhen-model-tiers__header .yizhen-model-tiers__subtitle { font-size: 14px; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-particle-bridge i { animation: none !important; }
}
/* Keep the performance cards in two columns when tablet width allows it. */
@media (min-width: 800px) and (max-width: 900px) {
  .yizhen-products-enhanced .yizhen-products-performance__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .yizhen-products-enhanced .yizhen-performance-card__sample {
    text-wrap: balance;
  }
}

/* Narrow desktop: keep both lines of the hero headline within its column. */
@media (min-width: 901px) and (max-width: 980px) {
  .yizhen-products-enhanced .yizhen-product-hero-title { font-size: clamp(43px, 4.8vw, 47px); }
}

/* Restore the reading hierarchy and align the three card actions. */
.yizhen-model-tiers .yizhen-model-tier__copy > p.yizhen-model-tier__question {
  max-width: 320px;
  min-height: 0;
  margin: 21px 0 0;
  color: #142f59;
  font-size: clamp(17px, 1.32vw, 19px);
  font-weight: 650;
  line-height: 1.48;
  letter-spacing: -.018em;
}
.yizhen-model-tiers .yizhen-model-tier__copy > p:not(.yizhen-model-tier__question) {
  max-width: 310px;
  margin-top: 10px;
  color: #526f91;
  font-size: 14px;
  line-height: 1.7;
}
.yizhen-model-tiers .yizhen-model-tier:not(.is-lens) .yizhen-model-tier__copy::after { display: none; }
.yizhen-model-tier__state { letter-spacing: .005em; }

/* Product-page controls share a quiet optical lift and a firm pressed state. */
.yizhen-products-enhanced .yizhen-model-tier__link,
.yizhen-products-enhanced .yizhen-model-tier__apply,
.yizhen-products-enhanced .detail-hero__actions a,
.yizhen-products-enhanced .header-action,
.yizhen-products-enhanced .detail-next a {
  transition: transform 220ms cubic-bezier(.22,.61,.36,1), box-shadow 220ms ease,
              border-color 220ms ease, background-color 220ms ease, filter 220ms ease;
}
.yizhen-products-enhanced .yizhen-model-tier__link:hover,
.yizhen-products-enhanced .detail-hero__actions a:first-child:hover {
  transform: translateY(-2px);
  box-shadow: 0 11px 22px rgba(13, 99, 191, .18);
  filter: brightness(1.035);
}
.yizhen-products-enhanced .yizhen-model-tier__apply:hover,
.yizhen-products-enhanced .detail-hero__actions a:nth-child(2):hover,
.yizhen-products-enhanced .header-action:hover,
.yizhen-products-enhanced .detail-next a:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 19px rgba(22, 91, 164, .09);
}
.yizhen-products-enhanced .yizhen-model-tier__link:active,
.yizhen-products-enhanced .yizhen-model-tier__apply:active,
.yizhen-products-enhanced .detail-hero__actions a:active,
.yizhen-products-enhanced .header-action:active,
.yizhen-products-enhanced .detail-next a:active { transform: translateY(0); box-shadow: none; }
.yizhen-products-enhanced .detail-hero__actions a:focus-visible,
.yizhen-products-enhanced .header-action:focus-visible,
.yizhen-products-enhanced .detail-next a:focus-visible { outline: 3px solid #2d84ef; outline-offset: 3px; }
.yizhen-beta-drawer__close {
  transition: border-color 200ms ease, background-color 200ms ease, transform 200ms ease;
}
.yizhen-beta-drawer__close:hover {
  border-color: #9dc3e9;
  background: #eef7ff;
  transform: rotate(8deg);
}
@media (max-width: 767px) {
  .yizhen-model-tiers .yizhen-model-tier__copy > p.yizhen-model-tier__question { margin-top: 18px; font-size: 17px; }
  .yizhen-model-tiers .yizhen-model-tier__copy > p:not(.yizhen-model-tier__question) { font-size: 13px; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-products-enhanced .yizhen-model-tier__link,
  .yizhen-products-enhanced .yizhen-model-tier__apply,
  .yizhen-products-enhanced .detail-hero__actions a,
  .yizhen-products-enhanced .header-action,
  .yizhen-products-enhanced .detail-next a,
  .yizhen-beta-drawer__close { transition: none; }
  .yizhen-products-enhanced .yizhen-model-tier__link:hover,
  .yizhen-products-enhanced .yizhen-model-tier__apply:hover,
  .yizhen-products-enhanced .detail-hero__actions a:hover,
  .yizhen-products-enhanced .header-action:hover,
  .yizhen-products-enhanced .detail-next a:hover,
  .yizhen-beta-drawer__close:hover,
  .yizhen-products-enhanced .detail-hero__actions a:first-child:hover span { transform: none; }
}

/* In the expanded compact menu, center the active mark beneath its label. */
@media (max-width: 900px) {
  .yizhen-products-enhanced .main-nav a[href="/products"]::after {
    left: 34px;
    right: auto;
    width: 24px;
  }
}

/* Beta application: the model and channel status lead; fields stay calm and legible. */
.yizhen-beta-drawer {
  border-left: 1px solid rgba(122, 165, 211, .28);
  background: radial-gradient(circle at 100% 0, rgba(118, 185, 244, .10), transparent 35%), #f8fbff;
}
.yizhen-beta-drawer__header {
  padding: 38px 38px 28px;
  background: linear-gradient(145deg, rgba(255,255,255,.96), rgba(239,247,255,.82));
}
.yizhen-beta-drawer__header::before {
  position: absolute;
  top: 0;
  left: 38px;
  width: 76px;
  height: 3px;
  border-radius: 0 0 3px 3px;
  background: linear-gradient(90deg, #0b74dc, #39afea);
  content: '';
}
.yizhen-beta-drawer__meta {
  display: flex;
  align-items: center;
  gap: 13px;
  max-width: calc(100% - 60px);
}
.yizhen-beta-drawer__status {
  display: inline-flex;
  align-items: center;
  min-height: 25px;
  padding: 0 9px;
  border: 1px solid #c9deef;
  border-radius: 999px;
  background: rgba(238, 247, 255, .84);
  color: #3e6d9a;
  font-size: 11px;
  font-weight: 650;
  line-height: 1;
  white-space: nowrap;
}
.yizhen-beta-drawer__status::before {
  width: 5px;
  height: 5px;
  margin-right: 6px;
  border-radius: 50%;
  background: #4d9bdb;
  content: '';
}
.yizhen-beta-drawer__header h2 {
  margin: 17px 0 8px;
  font-size: 31px;
  line-height: 1.2;
}
.yizhen-beta-drawer__header .yizhen-beta-drawer__intro {
  max-width: 370px;
  color: #597592;
  font-size: 14px;
  line-height: 1.65;
}
.yizhen-beta-form { gap: 20px; padding-top: 27px; }
.yizhen-beta-form__model {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 58px;
  margin: 0;
  padding: 0 17px;
  border: 1px solid #d8e7f5;
  border-radius: 12px;
  background: rgba(255,255,255,.76);
  color: #67819c;
  font-size: 12px;
}
.yizhen-beta-form__model strong {
  margin-left: 12px;
  color: #0a4585;
  font-size: 19px;
  font-weight: 720;
  letter-spacing: -.02em;
}
.yizhen-beta-form fieldset { gap: 10px; }
.yizhen-beta-form fieldset label {
  flex: 1;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid #d5e4f2;
  border-radius: 10px;
  background: #fff;
  color: #345879;
  transition: background-color 200ms ease, border-color 200ms ease, box-shadow 200ms ease;
}
.yizhen-beta-form fieldset label:has(input:checked) {
  border-color: #8ebce7;
  background: #edf7ff;
  color: #0c4e8e;
}
.yizhen-beta-form fieldset label:focus-within {
  outline: 2px solid #2d84ef;
  outline-offset: 2px;
}
.yizhen-beta-form input:not([type="radio"]),
.yizhen-beta-form select { min-height: 46px; }
.yizhen-beta-form__notice {
  margin-bottom: 14px;
  padding: 11px 13px;
  border-left: 3px solid #78b4e6;
  border-radius: 0 8px 8px 0;
  background: #eef6fd;
  color: #3e6388;
  font-size: 12.5px;
  line-height: 1.6;
}
.yizhen-beta-form__submit { transition: background-color 200ms ease, box-shadow 200ms ease, transform 200ms ease; }
.yizhen-beta-form__submit:not(:disabled):hover {
  background: #086bca;
  box-shadow: 0 9px 20px rgba(13, 99, 191, .14);
  transform: translateY(-2px);
}
.yizhen-beta-form__submit:not(:disabled):active { box-shadow: none; transform: none; }
@media (max-width: 767px) {
  .yizhen-beta-drawer__header { padding: 32px 24px 23px; }
  .yizhen-beta-drawer__header::before { left: 24px; }
  .yizhen-beta-drawer__header h2 { font-size: 29px; }
  .yizhen-beta-form { gap: 18px; padding-top: 24px; }
}
@media (prefers-reduced-motion: reduce) {
  .yizhen-beta-form fieldset label,
  .yizhen-beta-form__submit { transition: none; }
  .yizhen-beta-form__submit:not(:disabled):hover { transform: none; }
}

/* Product chapter seam: give the divider and label separate breathing room. */
.yizhen-products-enhanced .detail-content.yizhen-model-tiers{border-top:0}
.yizhen-products-enhanced .yizhen-model-tiers__header::before{display:block;width:100%;height:1px;margin:0 0 18px;background:linear-gradient(90deg,#b8d5f2 0%,#dfebf7 58%,transparent 100%);content:''}
.yizhen-products-enhanced .yizhen-model-tiers__header div>p:first-child{margin:0 0 15px;color:#3477bd;font-size:12px;font-weight:700;letter-spacing:.12em;line-height:1.35}
@media (min-width:901px){
  .yizhen-products-enhanced .yizhen-particle-bridge{transform:translateY(38px)}
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers{margin-top:12px}
}
@media (min-width:901px) and (min-height:1000px){
  .yizhen-products-enhanced .yizhen-particle-bridge{transform:translateY(60px)}
}
@media (max-width:900px){
  .yizhen-products-enhanced .yizhen-model-tiers__header::before{margin-bottom:15px}
  .yizhen-products-enhanced .yizhen-model-tiers__header div>p:first-child{font-size:11px;margin-bottom:13px}
}
@media (prefers-reduced-motion:reduce){.yizhen-products-enhanced .yizhen-particle-bridge{transform:none}}

/* Balance the vertical space around the left-aligned three-level story. */
@media (min-width:901px){
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers{padding-top:clamp(40px,calc(208px - 15vh),74px);margin-bottom:180px}
}
@media (min-width:768px) and (max-width:900px){
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers{padding-top:26px;margin-bottom:160px}
}
@media (max-width:767px){
  .yizhen-products-enhanced .detail-content.yizhen-model-tiers{padding-top:24px;margin-bottom:120px}
}