:root {
  --ink: #17212b;
  --muted: #5f6f7c;
  --line: rgba(23, 33, 43, 0.12);
  --paper: #fbfcfd;
  --panel: #ffffff;
  --blue: #0d6e8f;
  --teal: #0f9f87;
  --amber: #e8912d;
  --navy: #19324a;
  --shadow: 0 24px 60px rgba(18, 34, 48, 0.13);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(249, 252, 253, 0.92), rgba(255, 255, 255, 0.96)),
    var(--paper);
  font-family:
    Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  line-height: 1.65;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(18px, 4vw, 56px);
  color: #fff;
  background: rgba(10, 23, 34, 0.74);
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  font-weight: 700;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 8px;
  color: #062b34;
  background: #c4f3e8;
  box-shadow: inset 0 -8px 16px rgba(8, 105, 113, 0.12);
  font-size: 15px;
  letter-spacing: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(14px, 2vw, 28px);
  color: rgba(255, 255, 255, 0.84);
  font-size: 14px;
  white-space: nowrap;
}

.nav-links a {
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: #fff;
}

.hero {
  position: relative;
  display: grid;
  align-items: end;
  min-height: 92vh;
  overflow: hidden;
  color: #fff;
}

.hero-image,
.hero-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-image {
  object-fit: cover;
}

.hero-overlay {
  background:
    linear-gradient(90deg, rgba(5, 17, 27, 0.92) 0%, rgba(8, 27, 39, 0.74) 42%, rgba(8, 27, 39, 0.28) 100%),
    linear-gradient(0deg, rgba(6, 18, 28, 0.88) 0%, rgba(6, 18, 28, 0.12) 42%);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(920px, calc(100% - 36px));
  margin: 0 auto;
  padding: 142px 0 9vh;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #9ff4df;
}

h1,
h2,
h3,
p {
  overflow-wrap: break-word;
}

h1 {
  max-width: 780px;
  margin: 0;
  font-size: clamp(42px, 7vw, 84px);
  line-height: 1.05;
  letter-spacing: 0;
}

h2 {
  margin: 0;
  font-size: clamp(28px, 4vw, 48px);
  line-height: 1.16;
  letter-spacing: 0;
}

h3 {
  margin: 0 0 10px;
  font-size: 19px;
  line-height: 1.25;
}

.hero-copy {
  max-width: 670px;
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.84);
  font-size: clamp(17px, 2vw, 21px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 22px;
  border-radius: 8px;
  font-weight: 800;
}

.primary-action {
  color: #07313c;
  background: #9ff4df;
}

.secondary-action {
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.42);
}

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 42px;
}

.hero-stats span {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  min-height: 42px;
  padding: 9px 14px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  color: rgba(255, 255, 255, 0.82);
}

.hero-stats strong {
  color: #fff;
  font-size: 18px;
}

.section,
.case-section,
.cta-section,
.site-footer {
  width: min(1180px, calc(100% - 36px));
  margin: 0 auto;
}

.section {
  padding: 96px 0;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 34px;
}

.intro-grid,
.stack-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.intro-grid article,
.stack-grid article {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 16px 42px rgba(18, 34, 48, 0.06);
}

.icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 38px;
  margin-bottom: 22px;
  border-radius: 8px;
  color: #053641;
  background: #d8f8ef;
  font-weight: 900;
}

.intro-grid p,
.stack-grid p,
.case-copy p,
.cta-section p,
.site-footer p {
  margin: 0;
  color: var(--muted);
}

.case-section {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(360px, 1.14fr);
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
  padding: 76px 0;
}

.case-section.reverse {
  grid-template-columns: minmax(360px, 1.14fr) minmax(0, 0.86fr);
}

.case-section.reverse .case-copy {
  order: 2;
}

.case-copy p + p {
  margin-top: 16px;
}

.case-copy h2 {
  margin-bottom: 20px;
}

.feature-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 26px;
}

.feature-list span {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 7px 12px;
  border-radius: 8px;
  color: #12313d;
  background: #eef7fb;
  border: 1px solid #d6e8ee;
  font-size: 14px;
  font-weight: 700;
}

.diagram-panel {
  overflow: hidden;
  border: 1px solid rgba(13, 110, 143, 0.18);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}

.diagram-panel svg {
  display: block;
  width: 100%;
  height: auto;
}

.lane rect:first-child {
  fill: rgba(255, 255, 255, 0.82);
  stroke: rgba(13, 110, 143, 0.16);
}

.lane > text {
  fill: #1e5365;
  font-size: 22px;
  font-weight: 900;
}

.node rect,
.orbit-node rect,
.tag-cloud rect {
  filter: url(#softShadow);
  stroke-width: 1;
}

.node rect {
  fill: #fff;
  stroke: rgba(13, 110, 143, 0.15);
}

.node text,
.orbit-node text,
.tag-cloud text,
.hub text {
  font-family:
    Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  text-anchor: middle;
  fill: #183340;
  font-size: 17px;
  font-weight: 800;
}

.node.accent rect {
  fill: #dff8f1;
  stroke: #9ddccd;
}

.node.dark rect {
  fill: #18384a;
  stroke: #18384a;
}

.node.dark text {
  fill: #fff;
}

.node.warn rect {
  fill: #fff2d8;
  stroke: #f0bf67;
}

.arrow {
  fill: none;
  stroke: #1583a3;
  stroke-width: 5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.arrow.slim {
  stroke: #1aa887;
  stroke-width: 4;
}

.caption {
  fill: #315465;
  font-size: 17px;
  font-weight: 800;
}

.green {
  border-color: rgba(15, 159, 135, 0.2);
}

.hub circle {
  fill: #143b48;
  filter: url(#softShadow);
}

.hub text {
  fill: #fff;
}

.hub text:first-of-type {
  font-size: 23px;
}

.hub text:last-of-type {
  font-size: 16px;
  fill: rgba(255, 255, 255, 0.82);
}

.orbit-node rect {
  fill: #fff;
  stroke: rgba(15, 159, 135, 0.18);
}

.orbit-node text:first-of-type {
  font-size: 18px;
}

.orbit-node text:last-of-type {
  fill: #60717c;
  font-size: 15px;
}

.tag-cloud rect {
  fill: #e4faf2;
  stroke: #ace8d6;
}

.tag-cloud text {
  fill: #116351;
  font-size: 16px;
}

.architecture {
  padding-top: 86px;
}

.stack-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.stack-grid article {
  min-height: 190px;
  border-top: 5px solid var(--blue);
}

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

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

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

.cta-section {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  gap: 34px;
  align-items: center;
  margin-bottom: 92px;
  padding: clamp(30px, 5vw, 48px);
  border-radius: 8px;
  color: #fff;
  background: #173343;
  box-shadow: var(--shadow);
}

.cta-section .eyebrow {
  color: #9ff4df;
}

.cta-section p {
  color: rgba(255, 255, 255, 0.78);
  font-size: 17px;
}

.site-footer {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
  padding: 38px 0 46px;
  border-top: 1px solid var(--line);
}

.footer-brand {
  margin-bottom: 12px;
}

.site-footer p {
  max-width: 420px;
}

.footer-meta {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-size: 14px;
  text-align: right;
}

@media (max-width: 980px) {
  .site-header {
    position: absolute;
    align-items: flex-start;
  }

  .nav-links {
    display: none;
  }

  .hero {
    min-height: 760px;
  }

  .hero-overlay {
    background:
      linear-gradient(180deg, rgba(5, 17, 27, 0.78) 0%, rgba(6, 19, 30, 0.82) 52%, rgba(6, 19, 30, 0.94) 100%),
      linear-gradient(90deg, rgba(5, 17, 27, 0.66), rgba(5, 17, 27, 0.16));
  }

  .intro-grid,
  .stack-grid,
  .case-section,
  .case-section.reverse,
  .cta-section,
  .site-footer {
    grid-template-columns: 1fr;
  }

  .case-section.reverse .case-copy {
    order: 0;
  }

  .case-section,
  .section {
    padding: 56px 0;
  }

  .stack-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .site-footer {
    display: grid;
  }

  .footer-meta {
    text-align: left;
  }
}

@media (max-width: 640px) {
  .site-header {
    padding: 14px 18px;
  }

  .hero {
    min-height: 720px;
  }

  .hero-content {
    width: min(100% - 28px, 920px);
    padding-bottom: 58px;
  }

  h1 {
    font-size: 42px;
  }

  h2 {
    font-size: 30px;
  }

  .hero-actions a {
    width: 100%;
  }

  .hero-stats {
    display: grid;
    grid-template-columns: 1fr;
  }

  .intro-grid,
  .stack-grid {
    grid-template-columns: 1fr;
  }

  .intro-grid article,
  .stack-grid article {
    padding: 22px;
  }

  .case-section,
  .case-section.reverse {
    grid-template-columns: minmax(0, 1fr);
    width: min(100% - 28px, 1180px);
    gap: 24px;
  }

  .diagram-panel {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .diagram-panel svg {
    width: 760px;
    max-width: none;
  }

  .cta-section {
    width: min(100% - 28px, 1180px);
    margin-bottom: 56px;
    padding: 26px 22px;
  }
}