:root {
  color-scheme: light;
  --ink: #111513;
  --muted: #52615c;
  --paper: #f5f7f7;
  --white: #ffffff;
  --line: #d8e0de;
  --teal: #008c7a;
  --red: #c63d50;
  --green: #5e8d3e;
  --yellow: #c5a100;
  --charcoal: #151715;
  --shadow: 0 20px 60px rgba(17, 21, 19, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family:
    Inter, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial,
    sans-serif;
  background: var(--paper);
  color: var(--ink);
  letter-spacing: 0;
}

img {
  display: block;
  max-width: 100%;
}

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

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  padding: 0 32px;
  color: var(--white);
  background: rgba(17, 21, 19, 0.72);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
}

.brand-mark {
  width: 18px;
  height: 18px;
  border-radius: 4px;
  background:
    linear-gradient(90deg, var(--teal) 0 45%, transparent 45% 55%, var(--red) 55%),
    var(--white);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.78);
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--white);
}

.hero-section {
  position: relative;
  min-height: 82vh;
  display: flex;
  align-items: flex-end;
  overflow: hidden;
  color: var(--white);
  background: var(--charcoal);
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.78) contrast(1.05);
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(17, 21, 19, 0.25), rgba(17, 21, 19, 0.92)),
    linear-gradient(90deg, rgba(17, 21, 19, 0.86), rgba(17, 21, 19, 0.2));
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(980px, calc(100% - 48px));
  margin: 0 auto;
  padding: 126px 0 72px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 800;
}

.hero-section .eyebrow {
  color: #58e0cd;
}

h1,
h2,
h3,
h4,
p {
  margin-top: 0;
}

h1 {
  max-width: 900px;
  margin-bottom: 22px;
  font-size: 78px;
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 18px;
  font-size: 52px;
  line-height: 1.08;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 12px;
  font-size: 22px;
  line-height: 1.25;
  letter-spacing: 0;
}

h4 {
  margin-bottom: 8px;
  font-size: 15px;
}

p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.75;
}

.hero-copy {
  max-width: 760px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 19px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  min-height: 46px;
  padding: 0 18px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 800;
}

.primary-action {
  color: var(--white);
  background: var(--teal);
}

.secondary-action {
  color: var(--white);
  border: 1px solid rgba(255, 255, 255, 0.4);
}

.signal-band {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border-bottom: 1px solid var(--line);
}

.signal-item {
  min-height: 124px;
  padding: 26px;
  background: var(--white);
}

.signal-item strong {
  display: block;
  margin-bottom: 10px;
  font-size: 17px;
}

.signal-item span {
  color: var(--muted);
  line-height: 1.65;
}

.section {
  padding: 92px 32px;
}

.section-heading {
  width: min(980px, 100%);
  margin: 0 auto 42px;
}

.section-heading.compact {
  margin-bottom: 30px;
}

.section-heading p {
  max-width: 800px;
}

.value-grid {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.value-card,
.control-grid article {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 26px;
  box-shadow: 0 10px 32px rgba(17, 21, 19, 0.06);
}

.card-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 30px;
  margin-bottom: 42px;
  border-radius: 6px;
  color: var(--white);
  background: var(--charcoal);
  font-size: 13px;
  font-weight: 900;
}

.value-card:nth-child(2) .card-index {
  background: var(--teal);
}

.value-card:nth-child(3) .card-index {
  background: var(--red);
}

.value-card:nth-child(4) .card-index {
  background: var(--green);
}

.workflow-section {
  color: var(--white);
  background: var(--charcoal);
}

.workflow-section p {
  color: rgba(255, 255, 255, 0.72);
}

.workflow-layout {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 340px minmax(0, 1fr);
  gap: 24px;
  align-items: stretch;
}

.stage-rail {
  display: grid;
  gap: 10px;
}

.stage-button {
  appearance: none;
  width: 100%;
  min-height: 68px;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px;
  color: rgba(255, 255, 255, 0.72);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 8px;
  text-align: left;
  cursor: pointer;
  letter-spacing: 0;
}

.stage-button span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 38px;
  height: 38px;
  border-radius: 8px;
  color: var(--charcoal);
  background: rgba(255, 255, 255, 0.84);
  font-weight: 900;
}

.stage-button strong {
  font-size: 17px;
}

.stage-button.is-active {
  color: var(--white);
  background: rgba(0, 140, 122, 0.24);
  border-color: rgba(88, 224, 205, 0.62);
}

.stage-button.is-active span {
  color: var(--white);
  background: var(--teal);
}

.stage-panel {
  min-height: 458px;
  padding: 38px;
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(0, 140, 122, 0.22), rgba(198, 61, 80, 0.08)),
    #20231f;
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: var(--shadow);
}

.panel-topline {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 52px;
}

.panel-topline span {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 10px;
  border-radius: 6px;
  color: rgba(255, 255, 255, 0.82);
  background: rgba(255, 255, 255, 0.1);
  font-size: 13px;
  font-weight: 800;
}

.stage-panel h3 {
  font-size: 48px;
}

.stage-panel p {
  max-width: 760px;
  color: rgba(255, 255, 255, 0.78);
}

.panel-columns {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
  margin-top: 34px;
  padding-top: 28px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
}

.panel-columns h4 {
  color: #58e0cd;
}

.controls-section {
  background: #eef4f2;
}

.control-grid {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.control-grid article {
  border-top: 5px solid var(--teal);
}

.control-grid article:nth-child(2) {
  border-top-color: var(--red);
}

.control-grid article:nth-child(3) {
  border-top-color: var(--green);
}

.control-grid article:nth-child(4) {
  border-top-color: var(--yellow);
}

.efficiency-section {
  background: var(--white);
}

.impact-grid {
  width: min(1180px, 100%);
  margin: 0 auto 24px;
  display: grid;
  grid-template-columns: 1.15fr 1fr 1fr;
  gap: 16px;
}

.impact-card {
  min-height: 280px;
  padding: 28px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #f8fbfa;
}

.impact-card .card-index {
  margin-bottom: 24px;
}

.metric-card {
  color: var(--white);
  background:
    linear-gradient(135deg, rgba(0, 140, 122, 0.94), rgba(21, 23, 21, 0.96)),
    var(--charcoal);
  border-color: rgba(0, 140, 122, 0.28);
}

.metric-card p {
  color: rgba(255, 255, 255, 0.78);
}

.metric-value {
  display: block;
  margin-bottom: 28px;
  font-size: 62px;
  line-height: 1;
  font-weight: 900;
}

.production-compare {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.compare-column {
  padding: 30px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.compare-column h3 {
  font-size: 30px;
}

.compare-column ol {
  display: grid;
  gap: 12px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: compare;
}

.compare-column li {
  position: relative;
  min-height: 46px;
  padding: 10px 12px 10px 48px;
  border-radius: 8px;
  background: var(--white);
  color: var(--muted);
  line-height: 1.55;
  counter-increment: compare;
}

.compare-column li::before {
  content: counter(compare);
  position: absolute;
  top: 10px;
  left: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: 6px;
  color: var(--white);
  background: var(--red);
  font-size: 13px;
  font-weight: 900;
}

.stable-column {
  background: #edf8f5;
  border-color: rgba(0, 140, 122, 0.22);
}

.stable-column li::before {
  background: var(--teal);
}

.asset-section {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 0.75fr);
  gap: 48px;
  align-items: center;
  width: min(1180px, calc(100% - 64px));
  margin: 0 auto;
  padding-left: 0;
  padding-right: 0;
}

.asset-copy h2 {
  max-width: 720px;
}

.asset-list {
  display: grid;
  gap: 10px;
  padding: 0;
  margin: 30px 0 0;
  list-style: none;
}

.asset-list li {
  display: grid;
  grid-template-columns: 140px minmax(0, 1fr);
  align-items: center;
  min-height: 58px;
  padding: 0 18px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.asset-list span {
  color: var(--teal);
  font-weight: 900;
}

.asset-list strong {
  font-size: 16px;
}

.asset-visual {
  margin: 0;
  overflow: hidden;
  border-radius: 8px;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.asset-visual img {
  width: 100%;
  height: 440px;
  object-fit: cover;
  filter: saturate(0.86);
}

.asset-visual figcaption {
  padding: 14px 16px;
  color: var(--muted);
  font-size: 14px;
}

.principles-section {
  background: var(--white);
}

.principles-layout {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.principles-board {
  padding: 28px;
  border-radius: 8px;
  background: var(--charcoal);
  box-shadow: var(--shadow);
}

.principle-row {
  display: grid;
  grid-template-columns: 170px minmax(0, 1fr);
  gap: 18px;
  align-items: center;
  min-height: 62px;
  color: rgba(255, 255, 255, 0.72);
  border-bottom: 1px solid rgba(255, 255, 255, 0.11);
}

.principle-row:last-child {
  border-bottom: 0;
}

.principle-row span {
  font-weight: 800;
}

.principle-row b {
  display: block;
  height: 18px;
  border-radius: 4px;
  background:
    repeating-linear-gradient(
      90deg,
      rgba(255, 255, 255, 0.86) 0,
      rgba(255, 255, 255, 0.86) 18px,
      rgba(255, 255, 255, 0.22) 18px,
      rgba(255, 255, 255, 0.22) 30px
    );
}

.principles-copy {
  display: grid;
  gap: 18px;
}

.principles-copy h3 {
  margin-top: 4px;
}

.principles-copy ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.principles-copy li {
  position: relative;
  padding-left: 22px;
  color: var(--muted);
  line-height: 1.72;
}

.principles-copy li::before {
  content: "";
  position: absolute;
  top: 0.72em;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 2px;
  background: var(--red);
}

.principles-copy ul:first-of-type li::before {
  background: var(--teal);
}

.expansion-section {
  background: #eef4f2;
}

.expansion-grid {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.expansion-grid article {
  min-height: 218px;
  padding: 26px;
  border-radius: 8px;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: 0 10px 32px rgba(17, 21, 19, 0.06);
}

.expansion-grid .featured-extension {
  grid-column: span 2;
  color: var(--white);
  background:
    linear-gradient(135deg, rgba(21, 23, 21, 0.96), rgba(0, 140, 122, 0.86)),
    var(--charcoal);
  border-color: rgba(0, 140, 122, 0.3);
}

.expansion-grid .featured-extension p {
  max-width: 760px;
  color: rgba(255, 255, 255, 0.78);
}

.expansion-grid article::before {
  content: "";
  display: block;
  width: 44px;
  height: 6px;
  margin-bottom: 30px;
  border-radius: 3px;
  background: var(--teal);
}

.expansion-grid .featured-extension::before {
  width: 78px;
  background: var(--white);
}

.expansion-grid article:nth-child(3)::before,
.expansion-grid article:nth-child(6)::before {
  background: var(--red);
}

.expansion-grid article:nth-child(4)::before,
.expansion-grid article:nth-child(7)::before {
  background: var(--green);
}

.closing-section {
  color: var(--white);
  background: var(--charcoal);
}

.closing-inner {
  width: min(900px, 100%);
  margin: 0 auto;
  text-align: center;
}

.closing-inner p {
  color: rgba(255, 255, 255, 0.74);
}

@media (max-width: 980px) {
  .nav-links {
    display: none;
  }

  .signal-band,
  .value-grid,
  .control-grid,
  .impact-grid,
  .expansion-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .workflow-layout,
  .asset-section,
  .principles-layout,
  .production-compare {
    grid-template-columns: 1fr;
  }

  .stage-rail {
    grid-template-columns: repeat(2, 1fr);
  }

  .stage-button {
    min-height: 74px;
  }

  h1 {
    font-size: 56px;
  }

  h2 {
    font-size: 42px;
  }

  .stage-panel h3 {
    font-size: 38px;
  }
}

@media (max-width: 640px) {
  .site-header {
    min-height: 58px;
    padding: 0 18px;
  }

  .hero-section {
    min-height: 84vh;
  }

  .hero-content {
    width: min(100% - 32px, 980px);
    padding: 108px 0 46px;
  }

  h1 {
    font-size: 40px;
  }

  h2 {
    font-size: 31px;
  }

  p,
  .hero-copy {
    font-size: 16px;
  }

  .section {
    padding: 68px 18px;
  }

  .signal-band,
  .value-grid,
  .control-grid,
  .impact-grid,
  .expansion-grid,
  .stage-rail,
  .panel-columns {
    grid-template-columns: 1fr;
  }

  .signal-item {
    min-height: auto;
    padding: 22px 18px;
  }

  .stage-panel {
    min-height: 0;
    padding: 26px 20px;
  }

  .panel-topline {
    margin-bottom: 28px;
  }

  .asset-section {
    width: min(100% - 36px, 1180px);
  }

  .metric-value {
    font-size: 48px;
  }

  .expansion-grid .featured-extension {
    grid-column: auto;
  }

  .compare-column {
    padding: 22px 18px;
  }

  .asset-list li {
    grid-template-columns: 1fr;
    gap: 4px;
    padding: 14px;
  }

  .asset-visual img {
    height: 280px;
  }

  .principles-board {
    padding: 18px;
  }

  .principle-row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 14px 0;
  }
}