:root {
  --ink: #081923;
  --deep-ocean: #123142;
  --lab-paper: #eef3f4;
  --surface: #ffffff;
  --signal-teal: #087f73;
  --signal-teal-dark: #045248;
  --signal-teal-soft: #e6f5f3;
  --starlight-gold: #c48a1f;
  --text: #12242c;
  --text-secondary: #3a525c;
  --muted: #5a717b;
  --stroke: #c5d2d8;
  --stroke-soft: #d7e1e6;
  --font: system-ui, -apple-system, blinkmacsystemfont, "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  color-scheme: light;
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  margin: 0;
  background: var(--lab-paper);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-underline-offset: 4px;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button:focus-visible,
a:focus-visible {
  outline: 3px solid var(--signal-teal);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  z-index: 20;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  translate: 0 -160%;
  border-radius: 4px;
  background: var(--surface);
  color: var(--ink);
  font-weight: 700;
}

.skip-link:focus {
  translate: 0;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 76px;
  padding: 12px clamp(20px, 5vw, 72px);
  background: var(--ink);
  color: #eef4f8;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand img {
  width: 44px;
  height: 44px;
}

.brand span {
  display: grid;
}

.brand strong {
  font-size: 18px;
  letter-spacing: -0.02em;
}

.brand small {
  color: #c6dcdf;
  font-size: 12px;
}

.site-header nav {
  display: flex;
  gap: 24px;
  color: #c6d2d8;
  font-size: 14px;
  font-weight: 650;
}

.site-header nav a:hover {
  color: #ffffff;
}

main {
  width: min(100% - 40px, 1440px);
  margin: 0 auto;
}

.intro {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(300px, 0.7fr);
  gap: clamp(28px, 6vw, 88px);
  align-items: end;
  padding: clamp(64px, 9vw, 124px) 0 clamp(48px, 7vw, 84px);
}

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

h1 {
  max-width: 820px;
  margin-bottom: 24px;
  font-size: clamp(42px, 6.5vw, 88px);
  line-height: 0.98;
  letter-spacing: -0.055em;
  text-wrap: balance;
}

.intro > div > p {
  max-width: 760px;
  margin-bottom: 0;
  color: var(--text-secondary);
  font-size: clamp(18px, 2vw, 22px);
}

.simulation-boundary {
  display: grid;
  gap: 8px;
  padding: 22px 24px;
  border: 1px solid #9dcfc9;
  border-left: 5px solid var(--signal-teal);
  border-radius: 10px;
  background: var(--signal-teal-soft);
  color: var(--signal-teal-dark);
}

.simulation-boundary strong {
  font-size: 18px;
}

.simulation-boundary span {
  color: #245e5a;
  font-size: 14px;
}

.demo-shell {
  overflow: hidden;
  border: 1px solid var(--stroke);
  border-radius: 12px;
  background: var(--surface);
}

.demo-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 24px 28px;
  border-bottom: 1px solid var(--stroke-soft);
}

.demo-heading h2,
.scope h2 {
  margin-bottom: 4px;
  font-size: 20px;
  letter-spacing: -0.025em;
}

.demo-heading p,
.scope p {
  margin-bottom: 0;
  color: var(--muted);
}

.fixture-label {
  flex: none;
  color: var(--signal-teal-dark);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.view-tabs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-bottom: 1px solid var(--stroke);
  background: #f7fafb;
}

.view-tabs button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 58px;
  padding: 12px 18px;
  border: 0;
  border-right: 1px solid var(--stroke-soft);
  border-bottom: 4px solid transparent;
  background: transparent;
  color: var(--muted);
  font: 700 14px/1.3 var(--font);
  cursor: pointer;
}

.view-tabs button:last-child {
  border-right: 0;
}

.view-tabs button:hover {
  background: var(--signal-teal-soft);
  color: var(--signal-teal-dark);
}

.view-tabs button[aria-selected="true"] {
  border-bottom-color: var(--signal-teal);
  background: var(--surface);
  color: var(--text);
}

.view-tabs button span {
  color: var(--signal-teal);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 12px;
}

.view-panel {
  display: grid;
  grid-template-columns: minmax(250px, 0.32fr) minmax(0, 1fr);
  min-height: 620px;
}

.view-panel[hidden] {
  display: none;
}

.view-copy {
  padding: clamp(28px, 4vw, 52px);
  border-right: 1px solid var(--stroke-soft);
}

.step {
  margin-bottom: 22px;
  color: var(--signal-teal-dark);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.view-copy h3 {
  margin-bottom: 18px;
  font-size: clamp(26px, 3vw, 40px);
  line-height: 1.06;
  letter-spacing: -0.04em;
  text-wrap: balance;
}

.view-copy > p:not(.step) {
  color: var(--text-secondary);
}

.view-copy dl {
  margin: 36px 0 0;
  border-top: 1px solid var(--stroke-soft);
}

.view-copy dl div {
  display: grid;
  gap: 2px;
  padding: 12px 0;
  border-bottom: 1px solid var(--stroke-soft);
}

.view-copy dt {
  color: var(--muted);
  font-size: 12px;
  font-weight: 750;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.view-copy dd {
  margin: 0;
  font-size: 14px;
  font-weight: 650;
}

figure {
  display: grid;
  align-content: center;
  min-width: 0;
  margin: 0;
  padding: clamp(18px, 3vw, 36px);
  background: #e4ebed;
}

.capture-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid #aebfc7;
  border-radius: 8px;
  background: var(--ink);
  box-shadow: 0 12px 30px rgb(8 25 35 / 12%);
}

.capture-frame > span {
  position: absolute;
  z-index: 2;
  top: 10px;
  left: 10px;
  padding: 7px 10px;
  border: 1px solid rgb(255 255 255 / 24%);
  border-radius: 4px;
  background: rgb(8 25 35 / 94%);
  color: #ffffff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.capture-frame img {
  display: block;
  width: 100%;
  height: auto;
}

figcaption {
  margin-top: 12px;
  color: var(--muted);
  font-size: 13px;
}

.scope {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  margin: 40px 0 80px;
  border: 1px solid var(--stroke);
  border-radius: 12px;
  background: var(--stroke);
  overflow: hidden;
}

.scope > div {
  padding: 30px;
  background: var(--surface);
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 24px clamp(20px, 5vw, 72px);
  background: var(--ink);
  color: #c6d2d8;
  font-size: 14px;
}

footer p {
  margin: 0;
}

footer a {
  color: #ffffff;
  font-weight: 700;
}

@media (max-width: 900px) {
  .intro,
  .view-panel {
    grid-template-columns: 1fr;
  }

  .intro {
    align-items: start;
  }

  .view-copy {
    border-right: 0;
    border-bottom: 1px solid var(--stroke-soft);
  }

  .view-copy dl {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
  }

  .view-copy dl div {
    padding-right: 12px;
  }
}

@media (max-width: 680px) {
  .site-header,
  footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-header nav {
    gap: 18px;
  }

  main {
    width: min(100% - 24px, 1440px);
  }

  .intro {
    padding-top: 48px;
  }

  h1 {
    font-size: clamp(40px, 14vw, 62px);
  }

  .demo-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .view-tabs {
    grid-template-columns: 1fr;
  }

  .view-tabs button {
    justify-content: flex-start;
    border-right: 0;
    border-bottom-width: 1px;
    border-left: 4px solid transparent;
  }

  .view-tabs button[aria-selected="true"] {
    border-bottom-color: var(--stroke-soft);
    border-left-color: var(--signal-teal);
  }

  .view-copy dl,
  .scope {
    grid-template-columns: 1fr;
  }

  .capture-frame > span {
    position: static;
    display: block;
    border: 0;
    border-radius: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}