* { box-sizing: border-box; margin: 0; padding: 0; }
html { min-height: 100%; scroll-behavior: smooth; background: #090d13; }
body {
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #f3f7fb;
  background: #090d13;
  line-height: 1.6;
}
a { color: inherit; text-decoration: none; }
button, input, select { font: inherit; }
.shell {
  min-height: 100vh;
  background:
    radial-gradient(circle at 18% 8%, rgba(35, 123, 188, .25), transparent 32%),
    linear-gradient(120deg, #0b1320 0%, #111820 44%, #090d13 100%);
}
.image-rights-note {
  width: min(100% - 48px, 1180px);
  margin: 0 auto;
  padding: 22px 0 36px;
  color: rgba(226, 239, 255, .58);
  font-size: 13px;
  line-height: 1.7;
  text-align: center;
}
.topbar {
  position: fixed;
  inset: 0 0 auto;
  z-index: 30;
  height: 72px;
  display: grid;
  grid-template-columns: minmax(170px, 1fr) auto minmax(170px, 1fr);
  align-items: center;
  padding: 0 clamp(22px, 4vw, 58px);
  background: rgba(7, 11, 17, .78);
  border-bottom: 1px solid rgba(255, 255, 255, .09);
  backdrop-filter: blur(18px);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}
.brand-mark {
  width: 42px;
  height: 42px;
  display: block;
  border-radius: 6px;
  background: #fff;
  object-fit: cover;
}
.brand-text {
  display: grid;
  line-height: 1.1;
}
.brand-name {
  color: #fff;
  font-size: 18px;
  font-weight: 750;
  letter-spacing: .08em;
}
.brand-sub {
  color: rgba(224, 238, 255, .58);
  font-size: 10px;
  letter-spacing: .24em;
  margin-top: 3px;
}
.nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(24px, 4vw, 56px);
  color: rgba(244, 248, 255, .9);
  font-size: 17px;
  letter-spacing: .08em;
  white-space: nowrap;
}
.nav > a,
.nav-trigger,
.mode-trigger {
  position: relative;
  min-height: 72px;
  display: inline-flex;
  align-items: center;
  border: 0;
  background: transparent;
  color: inherit;
  cursor: pointer;
  padding: 26px 0 24px;
}
.nav-trigger {
  border-radius: 0;
  font: inherit;
  letter-spacing: inherit;
}
.nav > a::after,
.nav-trigger::after,
.mode-trigger::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 15px;
  width: 0;
  height: 2px;
  background: #2ec7ff;
  transform: translateX(-50%);
  transition: width .18s ease;
}
.nav > a:hover::after,
.nav > a:focus-visible::after,
.nav-item:hover .nav-trigger::after,
.nav-item:focus-within .nav-trigger::after,
.nav-item.open .nav-trigger::after,
.mode-menu:hover .mode-trigger::after,
.mode-menu.open .mode-trigger::after { width: 100%; }
.nav-trigger:hover,
.nav-trigger:focus-visible {
  color: #fff;
  outline: 0;
}
.nav-item {
  position: relative;
}
.product-menu {
  position: absolute;
  top: calc(100% - 4px);
  left: 50%;
  width: min(250px, calc(100vw - 32px));
  padding: 6px;
  border: 1px solid rgba(83, 190, 255, .24);
  border-radius: 8px;
  background: rgba(7, 13, 22, .94);
  box-shadow: 0 24px 80px rgba(0, 0, 0, .42);
  backdrop-filter: blur(18px);
  transform: translate(-50%, 8px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity .16s ease, transform .16s ease, visibility .16s ease;
}
.theory-menu {
  width: min(520px, calc(100vw - 32px));
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 8px;
  padding: 8px;
}
.theory-menu-primary {
  display: grid;
  align-content: start;
  gap: 6px;
  border-right: 1px solid rgba(83, 190, 255, .16);
  padding-right: 8px;
}
.theory-menu-guide {
  display: block;
  text-decoration: none;
}
.theory-menu-tab {
  min-height: 38px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: rgba(236, 246, 255, .78);
  cursor: pointer;
  font: inherit;
  font-size: 14px;
  letter-spacing: .04em;
  text-align: left;
  padding: 8px 10px;
}
.theory-menu-tab:hover,
.theory-menu-tab:focus-visible,
.theory-menu-tab.active {
  background: rgba(46, 199, 255, .13);
  color: #fff;
  outline: 0;
}
.theory-menu-panels {
  min-width: 0;
}
.theory-menu-panel {
  display: none;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
}
.theory-menu-panel.active {
  display: grid;
}
.nav-item:hover .product-menu,
.nav-item:focus-within .product-menu,
.nav-item.open .product-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translate(-50%, 0);
}
.product-option {
  width: 100%;
  min-height: 26px;
  display: block;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: rgba(236, 246, 255, .9);
  cursor: not-allowed;
  font: inherit;
  font-size: 14px;
  letter-spacing: .04em;
  line-height: 1.3;
  padding: 8px 11px;
  text-align: left;
}
.product-option-label {
  display: inline;
  min-width: 0;
}
.product-option-note {
  display: inline;
  margin-left: 8px;
  color: rgba(196, 216, 236, .62);
  font-size: 11px;
  letter-spacing: 0;
  line-height: 1.3;
}
.product-option-link {
  cursor: pointer;
}
.product-option + .product-option { margin-top: 2px; }
.product-option:hover,
.product-option:focus-visible {
  background: rgba(46, 199, 255, .12);
  color: #fff;
  outline: 0;
}
.new-badge {
  vertical-align: middle;
  min-width: 30px;
  min-height: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  background: #e60012;
  color: #fff;
  box-shadow: 0 0 18px rgba(230, 0, 18, .52);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: .06em;
  line-height: 1;
  padding: 3px 6px;
  margin-left: 6px;
}
.topbar-end {
  display: flex;
  justify-content: flex-end;
}
.mode-menu {
  position: relative;
}
.topbar-end .mode-menu {
  height: 72px;
  display: flex;
  align-items: center;
}
.mode-menu-mobile {
  display: none;
}
.mode-trigger {
  gap: 8px;
  color: rgba(244, 248, 255, .78);
  font-size: 14px;
  letter-spacing: .08em;
}
.mode-current {
  color: #2ec7ff;
  font-size: 11px;
  letter-spacing: .02em;
}
.mode-options {
  position: absolute;
  top: calc(100% - 4px);
  right: 0;
  width: 150px;
  padding: 7px;
  border: 1px solid rgba(83, 190, 255, .24);
  border-radius: 8px;
  background: rgba(7, 13, 22, .94);
  box-shadow: 0 24px 80px rgba(0, 0, 0, .42);
  backdrop-filter: blur(18px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity .16s ease, transform .16s ease, visibility .16s ease;
}
.mode-menu:hover .mode-options,
.mode-menu.open .mode-options {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}
.mode-menu.collapsed .mode-options {
  opacity: 0 !important;
  visibility: hidden !important;
  pointer-events: none !important;
  transform: translateY(8px) !important;
}
.theme-btn {
  width: 100%;
  min-height: 36px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: rgba(236, 246, 255, .86);
  cursor: pointer;
  font-size: 13px;
  text-align: left;
  padding: 0 10px;
}
.theme-btn:hover,
.theme-btn:focus-visible,
.theme-btn.active {
  background: rgba(46, 199, 255, .12);
  color: #fff;
  outline: 0;
}
.hero {
  min-height: 640px;
  display: grid;
  grid-template-columns: minmax(0, .92fr) minmax(420px, 1.08fr);
  align-items: center;
  gap: clamp(28px, 5vw, 72px);
  padding: 120px clamp(22px, 6vw, 84px) 58px;
}
.hero-media {
  min-height: 450px;
  overflow: hidden;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, .10);
  background: #0e1724;
  box-shadow: 0 30px 90px rgba(0, 0, 0, .28);
}
.hero-media img {
  width: 100%;
  height: 100%;
  min-height: 450px;
  display: block;
  object-fit: cover;
}
.hero-copy {
  max-width: 760px;
}
.eyebrow,
.section-kicker,
.focus-kicker {
  color: #57cdfc;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .16em;
}
h1 {
  margin-top: 12px;
  color: #fff;
  font-size: clamp(40px, 5vw, 68px);
  line-height: 1.08;
  font-weight: 820;
  letter-spacing: 0;
}
.hero-copy p:not(.eyebrow) {
  max-width: 620px;
  margin-top: 24px;
  color: rgba(232, 242, 255, .74);
  font-size: 17px;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}
.primary-link,
.secondary-link,
.focus-link,
.function-theory-row > a,
.classic-actions a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  padding: 0 18px;
  font-weight: 750;
}
.primary-link {
  background: #2ec7ff;
  color: #06111b;
}
.secondary-link,
.focus-link,
.function-theory-row > a,
.classic-actions a {
  border: 1px solid rgba(83, 190, 255, .28);
  color: #eaf7ff;
  background: rgba(255, 255, 255, .04);
}
.formula-band {
  width: min(1180px, calc(100% - 44px));
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, .82fr);
  align-items: stretch;
  gap: 12px;
  margin: 0 auto 34px;
}
.formula-card {
  min-height: 112px;
  display: grid;
  align-content: center;
  gap: 8px;
  border: 1px solid rgba(83, 190, 255, .18);
  border-radius: 8px;
  background: rgba(12, 22, 34, .76);
  padding: 18px;
}
.formula-card span {
  color: rgba(225, 239, 251, .62);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.35;
  white-space: nowrap;
}
.formula-card strong {
  color: #fff;
  font-size: 24px;
}
.formula-result {
  border-color: rgba(218, 170, 62, .30);
}
.formula-operator {
  display: grid;
  place-items: center;
  color: rgba(232, 242, 255, .62);
  font-size: 30px;
  font-weight: 300;
}
.model-entry {
  padding-top: 18px;
}
.model-entry-grid,
.type-model-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.type-model-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
.model-entry-card {
  min-height: 270px;
  display: grid;
  align-content: start;
  gap: 14px;
  border: 1px solid rgba(83, 190, 255, .18);
  border-radius: 8px;
  background: rgba(12, 22, 34, .76);
  padding: clamp(22px, 3vw, 30px);
}
.model-entry-card span {
  color: #57cdfc;
  font-size: 13px;
  font-weight: 850;
  letter-spacing: .14em;
}
.model-entry-card h2 {
  color: #fff;
  font-size: clamp(30px, 3vw, 44px);
  line-height: 1.16;
}
.model-entry-card p {
  color: rgba(232, 242, 255, .70);
  font-size: 16px;
  line-height: 1.82;
}
.model-entry-card .primary-link,
.model-entry-card .secondary-link {
  width: fit-content;
  margin-top: 8px;
}
.function-theory-row-featured {
  border-color: rgba(46, 199, 255, .36);
  background:
    linear-gradient(135deg, rgba(46, 199, 255, .13), rgba(12, 22, 34, .72) 52%),
    rgba(12, 22, 34, .72);
}
.section {
  width: min(1180px, calc(100% - 44px));
  margin: 0 auto;
  padding: 58px 0;
}
.section-head {
  max-width: 780px;
  margin-bottom: 24px;
}
.section-head h2 {
  margin-top: 8px;
  color: #fff;
  font-size: clamp(28px, 3vw, 42px);
  line-height: 1.18;
  letter-spacing: 0;
}
.section-title-link {
  color: inherit;
  text-decoration: none;
}
.section-title-link:hover,
.section-title-link:focus-visible {
  color: #57cdfc;
  outline: 0;
}
.section-head p:not(.section-kicker) {
  margin-top: 12px;
  color: rgba(232, 242, 255, .68);
}
.section-subtitle-nowrap {
  white-space: nowrap;
}
.matrix-tools {
  display: grid;
  grid-template-columns: minmax(150px, .8fr) minmax(160px, .9fr) minmax(240px, 1.4fr) auto;
  gap: 12px;
  align-items: end;
  margin-bottom: 16px;
}
.matrix-tools label {
  display: grid;
  gap: 6px;
  color: rgba(232, 242, 255, .68);
  font-size: 13px;
}
.matrix-tools select,
.matrix-tools input {
  width: 100%;
  min-height: 42px;
  border: 1px solid rgba(83, 190, 255, .22);
  border-radius: 8px;
  background: rgba(8, 15, 24, .8);
  color: #fff;
  padding: 0 12px;
  outline: 0;
}
.matrix-tools select:focus,
.matrix-tools input:focus {
  border-color: rgba(46, 199, 255, .68);
}
.reset-btn {
  min-height: 42px;
  border: 1px solid rgba(83, 190, 255, .22);
  border-radius: 8px;
  background: rgba(255, 255, 255, .04);
  color: #eaf7ff;
  cursor: pointer;
  padding: 0 16px;
}
.matrix-scroll {
  overflow: auto;
  border: 1px solid rgba(83, 190, 255, .18);
  border-radius: 8px;
  background: rgba(10, 18, 29, .72);
}
.type-matrix {
  width: 100%;
  min-width: 980px;
  border-collapse: collapse;
}
.type-matrix th,
.type-matrix td {
  width: 11.11%;
  border: 1px solid rgba(83, 190, 255, .14);
  vertical-align: top;
}
.type-matrix th {
  background: rgba(38, 70, 106, .56);
}
.matrix-corner {
  padding: 0;
}
.matrix-corner-box {
  position: relative;
  width: 100%;
  min-height: 112px;
  aspect-ratio: 1 / 1;
  overflow: hidden;
}
.matrix-corner-box::after {
  content: "";
  position: absolute;
  left: -25%;
  top: 50%;
  width: 150%;
  height: 1px;
  background: rgba(83, 190, 255, .22);
  transform: rotate(45deg);
  transform-origin: center;
}
.corner-label {
  position: absolute;
  z-index: 1;
  color: rgba(232, 242, 255, .86);
  font-size: 14px;
  font-weight: 850;
  letter-spacing: .04em;
  line-height: 1.25;
  white-space: nowrap;
}
.corner-label-interaction {
  top: 18px;
  right: 18px;
}
.corner-label-temperament {
  left: 18px;
  bottom: 18px;
}
.axis-btn,
.type-cell {
  width: 100%;
  height: 100%;
  min-height: 112px;
  display: grid;
  align-content: start;
  gap: 6px;
  border: 0;
  background: transparent;
  color: inherit;
  cursor: pointer;
  text-align: left;
  padding: 12px;
}
.axis-btn strong,
.type-cell strong {
  color: #fff;
  font-size: 18px;
  letter-spacing: .02em;
}
.axis-btn span,
.type-cell span {
  color: rgba(232, 242, 255, .76);
  font-size: 13px;
  line-height: 1.35;
}
.axis-btn em {
  color: rgba(232, 242, 255, .50);
  font-size: 12px;
  font-style: normal;
  line-height: 1.35;
}
.axis-btn .english-lines span {
  display: block;
}
.type-cell:hover,
.type-cell:focus-visible,
.axis-btn:hover,
.axis-btn:focus-visible {
  background: rgba(46, 199, 255, .10);
  outline: 0;
}
.is-dimmed {
  opacity: .24;
}
.focus-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-top: 16px;
  border: 1px solid rgba(83, 190, 255, .18);
  border-radius: 8px;
  background: rgba(12, 22, 34, .76);
  padding: 20px;
}
.focus-panel h3 {
  margin-top: 6px;
  color: #fff;
  font-size: 24px;
}
.focus-panel p:not(.focus-kicker) {
  margin-top: 8px;
  color: rgba(232, 242, 255, .70);
}
.focus-link {
  flex: 0 0 auto;
}
.card-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}
.info-card,
.reading-card {
  border: 1px solid rgba(83, 190, 255, .16);
  border-radius: 8px;
  background: rgba(12, 22, 34, .72);
  color: inherit;
  text-align: left;
  padding: 20px;
}
.info-card {
  min-height: 190px;
  cursor: pointer;
}
.info-card:hover,
.info-card:focus-visible,
.reading-card-link:hover,
.reading-card-link:focus-visible {
  border-color: rgba(46, 199, 255, .52);
  background: rgba(17, 33, 50, .82);
  outline: 0;
}
.reading-card-link {
  display: block;
}
.info-card span,
.reading-card span {
  color: #57cdfc;
  font-size: 13px;
  font-weight: 850;
  letter-spacing: .12em;
}
.info-card strong,
.reading-card h3 {
  display: block;
  margin-top: 8px;
  color: #fff;
  font-size: 21px;
}
.info-card em {
  display: block;
  color: rgba(232, 242, 255, .50);
  font-size: 13px;
  font-style: normal;
}
.info-card p,
.reading-card p {
  margin-top: 12px;
  color: rgba(232, 242, 255, .66);
}
.reading-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}
.classic {
  padding-bottom: 86px;
}
.function-theory-grid {
  display: grid;
  gap: 14px;
}
.function-theory-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 18px;
  border: 1px solid rgba(83, 190, 255, .16);
  border-radius: 8px;
  background: rgba(12, 22, 34, .62);
  padding: 18px;
}
.function-theory-row span {
  color: #57cdfc;
  font-size: 13px;
  font-weight: 850;
  letter-spacing: .12em;
}
.function-theory-row h3 {
  margin-top: 6px;
  color: #fff;
  font-size: 22px;
}
.function-theory-row p {
  margin-top: 8px;
  color: rgba(232, 242, 255, .66);
  line-height: 1.75;
}
.classic-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
html[data-theme="light"] {
  background: #f4f7fb;
}
html[data-theme="light"] body {
  color: #182538;
  background: #f4f7fb;
}
html[data-theme="light"] .shell {
  background:
    radial-gradient(circle at 18% 8%, rgba(46, 136, 196, .18), transparent 32%),
    linear-gradient(120deg, #f4f8fc 0%, #edf3f8 50%, #f8fafc 100%);
}
html[data-theme="light"] .topbar {
  background: rgba(255, 255, 255, .86);
  border-bottom-color: rgba(24, 47, 76, .10);
  box-shadow: 0 12px 34px rgba(20, 38, 62, .07);
}
html[data-theme="light"] .brand-name,
html[data-theme="light"] h1,
html[data-theme="light"] .model-entry-card h2,
html[data-theme="light"] .section-head h2,
html[data-theme="light"] .formula-card strong,
html[data-theme="light"] .focus-panel h3,
html[data-theme="light"] .info-card strong,
html[data-theme="light"] .reading-card h3,
html[data-theme="light"] .axis-btn strong,
html[data-theme="light"] .type-cell strong {
  color: #101827;
}
html[data-theme="light"] .brand-sub,
html[data-theme="light"] .nav,
html[data-theme="light"] .nav-trigger,
html[data-theme="light"] .mode-trigger {
  color: rgba(21, 32, 51, .76);
}
html[data-theme="light"] .hero-copy p:not(.eyebrow),
html[data-theme="light"] .model-entry-card p,
html[data-theme="light"] .section-head p:not(.section-kicker),
html[data-theme="light"] .focus-panel p:not(.focus-kicker),
html[data-theme="light"] .info-card p,
html[data-theme="light"] .reading-card p,
html[data-theme="light"] .axis-btn span,
html[data-theme="light"] .type-cell span {
  color: rgba(31, 45, 64, .68);
}
html[data-theme="light"] .formula-card,
html[data-theme="light"] .focus-panel,
html[data-theme="light"] .info-card,
html[data-theme="light"] .model-entry-card,
html[data-theme="light"] .reading-card,
html[data-theme="light"] .matrix-scroll {
  background: rgba(255, 255, 255, .82);
  border-color: rgba(28, 117, 175, .16);
}
html[data-theme="light"] .formula-card span,
html[data-theme="light"] .info-card em,
html[data-theme="light"] .axis-btn em {
  color: rgba(41, 60, 84, .54);
}
html[data-theme="light"] .type-matrix th {
  background: rgba(218, 229, 240, .84);
}
html[data-theme="light"] .corner-label {
  color: rgba(16, 24, 39, .86);
}
html[data-theme="light"] .matrix-corner-box::after {
  background: rgba(28, 117, 175, .28);
}
html[data-theme="light"] .type-matrix th,
html[data-theme="light"] .type-matrix td {
  border-color: rgba(28, 117, 175, .16);
}
html[data-theme="light"] .matrix-tools label {
  color: rgba(31, 45, 64, .68);
}
html[data-theme="light"] .matrix-tools select,
html[data-theme="light"] .matrix-tools input {
  background: rgba(255, 255, 255, .90);
  border-color: rgba(28, 117, 175, .18);
  color: #101827;
}
html[data-theme="light"] .secondary-link,
html[data-theme="light"] .focus-link,
html[data-theme="light"] .function-theory-row > a,
html[data-theme="light"] .classic-actions a,
html[data-theme="light"] .reset-btn {
  background: rgba(255, 255, 255, .62);
  border-color: rgba(28, 117, 175, .18);
  color: #182538;
}
html[data-theme="light"] .function-theory-row {
  background: rgba(255, 255, 255, .82);
  border-color: rgba(28, 117, 175, .16);
}
html[data-theme="light"] .function-theory-row h3 {
  color: #101827;
}
html[data-theme="light"] .function-theory-row p {
  color: rgba(31, 45, 64, .66);
}
html[data-theme="light"] .mode-options {
  background: rgba(248, 251, 255, .96);
  border-color: rgba(28, 117, 175, .20);
  box-shadow: 0 24px 72px rgba(23, 45, 72, .18);
}
html[data-theme="light"] .product-menu {
  background: rgba(248, 251, 255, .96);
  border-color: rgba(28, 117, 175, .20);
  box-shadow: 0 24px 72px rgba(23, 45, 72, .18);
}
html[data-theme="light"] .theory-menu-primary {
  border-right-color: rgba(28, 117, 175, .14);
}
html[data-theme="light"] .theory-menu-tab {
  color: rgba(21, 32, 51, .70);
}
html[data-theme="light"] .theory-menu-tab:hover,
html[data-theme="light"] .theory-menu-tab:focus-visible,
html[data-theme="light"] .theory-menu-tab.active {
  background: rgba(28, 117, 175, .09);
  color: #101827;
}
html[data-theme="light"] .image-rights-note {
  color: rgba(55, 71, 92, .62);
}
html[data-theme="light"] .product-option {
  color: rgba(21, 32, 51, .80);
}
html[data-theme="light"] .product-option-note {
  color: rgba(41, 60, 84, .54);
}
html[data-theme="light"] .product-option:hover,
html[data-theme="light"] .product-option:focus-visible {
  background: rgba(28, 117, 175, .09);
  color: #101827;
}
html[data-theme="light"] .theme-btn {
  color: rgba(21, 32, 51, .70);
}
html[data-theme="light"] .theme-btn:hover,
html[data-theme="light"] .theme-btn:focus-visible,
html[data-theme="light"] .theme-btn.active {
  background: rgba(28, 117, 175, .09);
  color: #101827;
}
@media (max-width: 1080px) {
  .hero {
    grid-template-columns: 1fr;
  }
  .hero-media {
    min-height: 320px;
    order: 2;
  }
  .hero-media img {
    min-height: 320px;
  }
  .formula-band {
    grid-template-columns: 1fr;
  }
  .formula-card span {
    white-space: normal;
  }
  .formula-operator {
    min-height: 20px;
  }
  .card-grid,
  .reading-grid,
  .model-entry-grid,
  .type-model-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}
@media (max-width: 760px) {
  .topbar {
    height: auto;
    min-height: 68px;
    grid-template-columns: 1fr auto;
    padding: 12px 18px 14px;
  }
  .brand {
    grid-column: 1;
    grid-row: 1;
    justify-content: flex-start;
  }
  .brand-mark {
    width: 40px;
    height: 40px;
  }
  .brand-name {
    font-size: 18px;
  }
  .topbar-end {
    grid-column: 2;
    grid-row: 1;
    display: flex;
    justify-content: flex-end;
  }
  .topbar-end .mode-menu {
    height: 40px;
  }
  .nav {
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    justify-content: stretch;
    gap: 0;
    overflow: visible;
    font-size: 14px;
  }
  .mode-menu-mobile { display: none; }
  .nav > a,
  .nav-trigger {
    width: 100%;
    padding: 4px 0;
    text-align: center;
  }
  .nav > a::after,
  .nav-trigger::after {
    bottom: -4px;
  }
  .topbar-end .mode-trigger {
    min-height: 40px;
    padding: 0;
    justify-content: flex-end;
  }
  .topbar-end .mode-trigger::after {
    bottom: -5px;
  }
  .nav-item { position: static; }
  .product-menu,
  .mode-options {
    position: fixed;
    top: 178px;
    left: 16px;
    right: 16px;
    width: auto;
    transform: translateY(8px);
  }
  .product-menu {
    left: 50%;
    right: auto;
    width: min(330px, calc(100vw - 64px));
    display: grid;
    gap: 2px;
    padding: 7px;
    transform: translate(-50%, 8px);
  }
  .theory-menu {
    left: 16px;
    right: 16px;
    width: auto;
    grid-template-columns: minmax(0, .86fr) minmax(0, 1.14fr);
    gap: 7px;
    transform: translateY(8px);
  }
  .theory-menu-primary {
    border-right: 1px solid rgba(83, 190, 255, .16);
    padding-right: 7px;
  }
  .theory-menu-tab {
    min-height: 44px;
    font-size: 13px;
    padding: 9px 8px;
  }
  .theory-menu-panel {
    grid-template-columns: 1fr;
    gap: 2px;
  }
  .product-option {
    min-height: 42px;
    display: block;
    font-size: 14px;
    padding: 10px 12px;
    text-align: left;
  }
  .new-badge {
    min-width: 34px;
    min-height: 21px;
    font-size: 12px;
    padding: 4px 7px;
  }
  .mode-options {
    display: grid;
    gap: 4px;
    padding: 10px;
  }
  .mode-options .theme-btn {
    min-height: 42px;
    display: flex;
    align-items: center;
    border-radius: 6px;
    font-size: 13px;
    padding: 9px 12px;
  }
  .nav-item:hover .product-menu,
  .nav-item:focus-within .product-menu,
  .nav-item.open .product-menu,
  .product-menu:hover {
    transform: translate(-50%, 0);
  }
  .nav-item:hover .theory-menu,
  .nav-item:focus-within .theory-menu,
  .nav-item.open .theory-menu,
  .theory-menu:hover {
    transform: translateY(0);
  }
  .mode-menu:hover .mode-options,
  .mode-menu.open .mode-options {
    transform: translateY(0);
  }
  .hero {
    min-height: auto;
    padding: 178px 16px 34px;
  }
  h1 {
    font-size: 34px;
  }
  .hero-copy p:not(.eyebrow) {
    font-size: 15px;
  }
  .section,
  .formula-band {
    width: calc(100% - 32px);
  }
  .section-subtitle-nowrap {
    white-space: normal;
  }
  .matrix-tools {
    grid-template-columns: 1fr;
  }
  .focus-panel {
    display: grid;
  }
  .card-grid,
  .reading-grid,
  .model-entry-grid,
  .type-model-grid {
    grid-template-columns: 1fr;
  }
  .function-theory-row {
    grid-template-columns: 1fr;
  }
  .classic-actions a,
  .function-theory-row > a {
    width: 100%;
  }
  .type-matrix {
    min-width: 860px;
  }
}