:root {
  --ink: #25180f;
  --ink-soft: #5d4938;
  --muted: #816a55;
  --paper: #fff8ed;
  --paper-deep: #f6e4ca;
  --warm: #d9903c;
  --warm-deep: #9b5a20;
  --earth: #6e4d31;
  --mocha: #2b1c13;
  --line: rgba(98, 65, 32, 0.16);
  --shadow: 0 22px 70px rgba(74, 43, 16, 0.16);
  --shadow-lift: 0 28px 78px rgba(74, 43, 16, 0.22);
  --radius: 8px;
  color-scheme: light;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
}

body.menu-open {
  overflow: hidden;
}

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

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

button {
  font: inherit;
}

.site-header {
  position: fixed;
  z-index: 30;
  top: 0;
  left: 0;
  right: 0;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  min-height: 76px;
  padding: 16px clamp(20px, 5vw, 72px);
  color: var(--ink);
  transition:
    background 220ms ease,
    box-shadow 220ms ease,
    color 220ms ease,
    min-height 220ms ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  min-height: 64px;
  background: rgba(255, 248, 237, 0.88);
  box-shadow: 0 14px 42px rgba(67, 43, 19, 0.12);
  color: var(--ink);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  width: max-content;
  font-size: 0.95rem;
  font-weight: 750;
  letter-spacing: 0;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 14px;
  background: rgba(255, 250, 241, 0.7);
  box-shadow: 0 10px 24px rgba(97, 52, 15, 0.1);
  overflow: hidden;
}

.brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.site-header.is-scrolled .brand-mark,
.site-header.is-open .brand-mark {
  background: rgba(255, 250, 241, 0.88);
  box-shadow: 0 8px 18px rgba(97, 52, 15, 0.12);
}

.desktop-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(18px, 3vw, 36px);
  color: inherit;
  font-size: 0.86rem;
  font-weight: 650;
}

.desktop-nav a {
  opacity: 0.78;
  transition:
    opacity 160ms ease,
    transform 160ms ease;
}

.desktop-nav a:hover,
.desktop-nav a.is-active {
  opacity: 1;
  transform: translateY(-1px);
}

.header-action {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-width: 112px;
  min-height: 42px;
  padding: 0 16px;
  border: 1px solid rgba(155, 90, 32, 0.24);
  border-radius: 999px;
  background: rgba(255, 248, 237, 0.54);
  font-size: 0.86rem;
  font-weight: 750;
  transition:
    background 160ms ease,
    box-shadow 160ms ease,
    transform 160ms ease;
}

.header-action:hover {
  transform: translateY(-1px);
  background: rgba(255, 248, 237, 0.78);
  box-shadow: 0 12px 32px rgba(74, 43, 16, 0.12);
}

.site-header.is-scrolled .header-action,
.site-header.is-open .header-action {
  border-color: rgba(155, 90, 32, 0.2);
  background: var(--ink);
  color: #fff8ed;
}

.header-action svg,
.primary-button svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.menu-button {
  display: none;
  justify-self: end;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(155, 90, 32, 0.24);
  border-radius: 50%;
  background: rgba(255, 248, 237, 0.58);
  color: inherit;
  cursor: pointer;
}

.menu-button span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  border-radius: 999px;
  background: currentColor;
  transition:
    transform 180ms ease,
    opacity 180ms ease;
}

.site-header.is-scrolled .menu-button,
.site-header.is-open .menu-button {
  border-color: rgba(155, 90, 32, 0.2);
  background: #fff1dd;
}

.menu-open .menu-button span:first-child {
  transform: translateY(3.5px) rotate(45deg);
}

.menu-open .menu-button span:last-child {
  transform: translateY(-3.5px) rotate(-45deg);
}

.mobile-nav {
  position: fixed;
  z-index: 24;
  top: 72px;
  left: 16px;
  right: 16px;
  display: grid;
  gap: 2px;
  padding: 14px;
  border: 1px solid rgba(97, 65, 33, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 248, 237, 0.96);
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transform: translateY(-10px);
  transition:
    opacity 180ms ease,
    transform 180ms ease;
  backdrop-filter: blur(18px);
}

.mobile-nav.is-open {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.mobile-nav a {
  padding: 14px 12px;
  border-radius: 6px;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 700;
}

.mobile-nav a:hover {
  background: #fff0dc;
}

.hero {
  position: relative;
  display: grid;
  min-height: 100svh;
  overflow: hidden;
  background:
    linear-gradient(90deg, rgba(255, 248, 237, 0.96) 0%, rgba(255, 240, 221, 0.86) 34%, rgba(255, 230, 189, 0.28) 58%, rgba(255, 229, 188, 0.02) 74%),
    linear-gradient(180deg, rgba(255, 248, 237, 0.06), rgba(255, 248, 237, 0.02) 46%, rgba(255, 248, 237, 0.92) 100%),
    url("assets/hero-study.png") center / cover no-repeat;
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 18vh;
  background: linear-gradient(180deg, rgba(255, 248, 237, 0), var(--paper));
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  align-self: center;
  width: min(680px, calc(100% - 40px));
  margin-left: clamp(20px, 7vw, 104px);
  padding-top: 88px;
  color: var(--ink);
}

.hero-content.reveal {
  opacity: 1;
  transform: none;
  animation: hero-in 760ms ease both;
}

@keyframes hero-in {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.company-line {
  margin: 0 0 22px;
  color: var(--warm-deep);
  font-size: clamp(0.78rem, 1.2vw, 0.94rem);
  font-weight: 700;
  line-height: 1.4;
}

.hero h1 {
  max-width: 620px;
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(4.1rem, 8vw, 8.6rem);
  font-weight: 500;
  line-height: 0.9;
  letter-spacing: 0;
}

.hero-lede {
  max-width: 620px;
  margin: 26px 0 0;
  font-size: clamp(1.46rem, 3vw, 3.15rem);
  font-weight: 650;
  line-height: 1.08;
}

.hero-copy {
  max-width: 560px;
  margin: 22px 0 0;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.35vw, 1.18rem);
  line-height: 1.72;
}

.hero-proof {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  max-width: 560px;
  margin-top: 24px;
}

.hero-proof span {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 0 13px;
  border: 1px solid rgba(155, 90, 32, 0.18);
  border-radius: 999px;
  background: rgba(255, 248, 237, 0.68);
  color: var(--warm-deep);
  font-size: 0.82rem;
  font-weight: 780;
  box-shadow: 0 10px 28px rgba(98, 65, 32, 0.08);
  transition:
    transform 180ms ease,
    background 180ms ease,
    box-shadow 180ms ease;
}

.hero-proof span:hover {
  transform: translateY(-2px);
  background: #fff8ed;
  box-shadow: 0 18px 38px rgba(98, 65, 32, 0.14);
}

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

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 780;
  transition:
    transform 180ms ease,
    box-shadow 180ms ease,
    background 180ms ease;
}

.primary-button {
  gap: 10px;
  padding: 0 22px 0 24px;
  background: var(--ink);
  color: #fff8ed;
  box-shadow: 0 18px 45px rgba(0, 0, 0, 0.18);
}

.primary-button:hover,
.secondary-button:hover {
  transform: translateY(-2px);
}

.secondary-button {
  padding: 0 22px;
  border: 1px solid rgba(155, 90, 32, 0.24);
  background: rgba(255, 248, 237, 0.56);
  color: var(--ink);
}

.scroll-cue {
  position: absolute;
  z-index: 3;
  left: 50%;
  bottom: 30px;
  display: grid;
  width: 32px;
  height: 52px;
  place-items: start center;
  border: 1px solid rgba(37, 24, 15, 0.32);
  border-radius: 999px;
  transform: translateX(-50%);
}

.scroll-cue span {
  width: 5px;
  height: 9px;
  margin-top: 10px;
  border-radius: 999px;
  background: var(--ink);
  animation: cue 1.7s ease-in-out infinite;
}

@keyframes cue {
  0%,
  100% {
    opacity: 0.35;
    transform: translateY(0);
  }
  50% {
    opacity: 1;
    transform: translateY(14px);
  }
}

.section {
  padding: clamp(76px, 10vw, 138px) clamp(20px, 5vw, 72px);
}

.section-inner {
  width: min(1180px, 100%);
  margin: 0 auto;
}

.split-layout,
.edge-layout,
.loop-layout,
.model-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(34px, 6vw, 82px);
  align-items: center;
}

.section-label,
.panel-kicker {
  margin: 0 0 14px;
  color: var(--warm-deep);
  font-size: 0.8rem;
  font-weight: 850;
  line-height: 1.4;
  text-transform: uppercase;
}

.section h2,
.closing-content h2 {
  margin: 0;
  max-width: 860px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.35rem, 4.6vw, 5rem);
  font-weight: 500;
  line-height: 1.07;
  letter-spacing: 0;
}

.section-copy > p:not(.section-label),
.section-heading > p:not(.section-label),
.closing-content p {
  max-width: 690px;
  margin: 24px 0 0;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.4vw, 1.18rem);
  line-height: 1.78;
}

.section-heading {
  display: grid;
  gap: 0;
  justify-items: center;
  text-align: center;
}

.section-heading p:not(.section-label) {
  margin-left: auto;
  margin-right: auto;
}

.problem-section {
  background:
    radial-gradient(circle at 18% 8%, rgba(255, 204, 127, 0.42), rgba(255, 204, 127, 0) 30%),
    var(--paper);
}

.problem-grid {
  display: grid;
  gap: 16px;
}

.problem-grid article,
.hardware-list article,
.model-cards article,
.team-card,
.milestone-card,
.comparison > div {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.58);
  box-shadow: 0 16px 46px rgba(100, 61, 23, 0.08);
  transition:
    transform 220ms ease,
    border-color 220ms ease,
    box-shadow 220ms ease,
    background 220ms ease;
}

.problem-grid article:hover,
.hardware-list article:hover,
.model-cards article:hover,
.team-card:hover,
.milestone-card:hover,
.comparison > div:hover,
.device-panel:hover,
.loop-card:hover {
  transform: translateY(-5px);
  border-color: rgba(155, 90, 32, 0.3);
  box-shadow: var(--shadow-lift);
}

.problem-grid article {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 6px 18px;
  padding: clamp(20px, 2.8vw, 28px);
}

.problem-grid span {
  grid-row: span 2;
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 50%;
  background: #fff0dc;
  color: var(--warm-deep);
  font-size: 0.8rem;
  font-weight: 850;
}

.problem-grid h3,
.device-panel h3,
.hardware-list h3,
.loop-card h3 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(1.12rem, 1.5vw, 1.34rem);
  line-height: 1.18;
}

.problem-grid p,
.hardware-list p,
.comparison span,
.device-panel li,
.loop-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.62;
}

.solution-section {
  background: #fffaf2;
}

.solution-system {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 180px minmax(0, 1fr);
  gap: 22px;
  align-items: stretch;
  margin-top: clamp(42px, 6vw, 72px);
}

.device-panel {
  display: grid;
  grid-template-rows: 260px 1fr;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff8ed;
  box-shadow: var(--shadow);
  transition:
    transform 220ms ease,
    border-color 220ms ease,
    box-shadow 220ms ease;
}

.device-panel img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 520ms ease;
}

.device-panel:hover img {
  transform: scale(1.035);
}

.device-panel > div {
  padding: clamp(22px, 3vw, 30px);
}

.device-panel ul {
  display: grid;
  gap: 10px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.device-panel li {
  position: relative;
  padding-left: 20px;
}

.device-panel li::before {
  content: "";
  position: absolute;
  top: 0.7em;
  left: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--warm);
}

.agent-core {
  position: relative;
  display: grid;
  align-content: center;
  justify-items: center;
  min-height: 100%;
  padding: 28px 18px;
  border: 1px solid rgba(155, 90, 32, 0.22);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #fff3df, #f4d4a8);
  text-align: center;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.58);
}

.agent-core::before,
.agent-core::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 28px;
  height: 1px;
  background: rgba(155, 90, 32, 0.34);
}

.agent-core::before {
  left: -28px;
}

.agent-core::after {
  right: -28px;
}

.agent-core span {
  color: var(--warm-deep);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 2rem;
  line-height: 1;
}

.agent-core p {
  margin: 14px 0 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
  font-weight: 700;
  line-height: 1.45;
}

.loop-section {
  background:
    linear-gradient(90deg, rgba(217, 144, 60, 0.12), rgba(217, 144, 60, 0)),
    var(--paper);
}

.loop-layout {
  grid-template-columns: minmax(0, 0.96fr) minmax(320px, 0.72fr);
  align-items: start;
}

.loop-controls {
  display: grid;
  gap: 10px;
  margin-top: 34px;
}

.loop-step {
  display: flex;
  align-items: center;
  gap: 13px;
  min-height: 54px;
  width: 100%;
  padding: 10px 14px;
  border: 1px solid rgba(97, 65, 33, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.42);
  color: var(--ink-soft);
  font-size: 0.98rem;
  font-weight: 760;
  text-align: left;
  cursor: pointer;
  transition:
    background 160ms ease,
    border-color 160ms ease,
    color 160ms ease,
    transform 160ms ease;
}

.loop-step:hover,
.loop-step.is-active {
  border-color: rgba(155, 90, 32, 0.34);
  background: #fff1dd;
  color: var(--ink);
  transform: translateX(4px);
}

.loop-step span {
  display: grid;
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
  place-items: center;
  border-radius: 50%;
  background: rgba(217, 144, 60, 0.14);
  color: var(--warm-deep);
  font-size: 0.76rem;
  font-weight: 900;
}

.loop-card {
  position: sticky;
  top: 96px;
  min-height: 520px;
  padding: clamp(26px, 4vw, 38px);
  border: 1px solid rgba(97, 65, 33, 0.15);
  border-radius: var(--radius);
  background:
    linear-gradient(145deg, rgba(255, 248, 237, 0.94), rgba(255, 240, 219, 0.82)),
    url("assets/hero-study.png") 67% 50% / 150% auto no-repeat;
  box-shadow: var(--shadow);
  overflow: hidden;
  transition:
    transform 220ms ease,
    border-color 220ms ease,
    box-shadow 220ms ease;
}

.loop-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255, 248, 237, 0.92), rgba(255, 248, 237, 0.74));
}

.loop-card > * {
  position: relative;
  z-index: 1;
}

.loop-card-top {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 58px;
}

.loop-card-top span {
  display: grid;
  width: 54px;
  height: 54px;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: #fff8ed;
  font-size: 0.95rem;
  font-weight: 850;
}

.loop-card-top p {
  color: var(--warm-deep);
  font-size: 0.82rem;
  font-weight: 850;
  line-height: 1.3;
  text-transform: uppercase;
}

.loop-card h3 {
  max-width: 430px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2rem, 4vw, 3.5rem);
  font-weight: 500;
  line-height: 1;
}

.loop-card > p {
  max-width: 420px;
  margin-top: 22px;
  color: var(--ink-soft);
}

.loop-card.is-changing {
  animation: card-pulse 360ms ease;
}

.hardware-section {
  background:
    linear-gradient(180deg, #fffaf2 0%, #fff4e4 100%);
}

@keyframes card-pulse {
  0% {
    transform: translateY(0) scale(0.988);
    opacity: 0.82;
  }
  100% {
    transform: translateY(0) scale(1);
    opacity: 1;
  }
}

.hardware-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: clamp(40px, 6vw, 68px);
}

.hardware-list article {
  padding: clamp(22px, 3vw, 32px);
}

.hardware-list h3 {
  margin-bottom: 18px;
}

.model-section {
  background:
    radial-gradient(circle at 82% 16%, rgba(47, 97, 72, 0.12), rgba(47, 97, 72, 0) 28%),
    var(--paper);
}

.model-layout {
  grid-template-columns: minmax(0, 0.98fr) minmax(320px, 0.86fr);
}

.model-cards {
  display: grid;
  gap: 16px;
}

.model-cards article {
  padding: clamp(24px, 3.5vw, 36px);
  background: rgba(255, 255, 255, 0.66);
}

.model-cards span {
  display: inline-flex;
  margin-bottom: 18px;
  color: var(--warm-deep);
  font-size: 0.78rem;
  font-weight: 850;
  line-height: 1.4;
  text-transform: uppercase;
}

.model-cards h3 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(1.12rem, 1.8vw, 1.46rem);
  line-height: 1.18;
}

.model-cards p {
  margin: 12px 0 0;
  color: var(--earth);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2rem, 4vw, 3.8rem);
  line-height: 0.98;
}

.model-cards small {
  display: block;
  margin-top: 18px;
  color: var(--muted);
  font-size: 0.96rem;
  line-height: 1.6;
}

.edge-section {
  background:
    radial-gradient(circle at 84% 16%, rgba(217, 144, 60, 0.18), rgba(217, 144, 60, 0) 34%),
    linear-gradient(135deg, #352318 0%, #241710 62%, #1d120c 100%);
  color: #fff8ed;
}

.edge-section .section-label {
  color: #f8ca88;
}

.edge-section .section-copy > p:not(.section-label) {
  color: rgba(255, 248, 237, 0.74);
}

.comparison {
  display: grid;
  gap: 16px;
}

.comparison > div {
  padding: clamp(24px, 3vw, 32px);
  background: rgba(255, 248, 237, 0.08);
  border-color: rgba(255, 248, 237, 0.15);
}

.comparison .is-highlighted {
  background: #fff8ed;
  color: var(--ink);
}

.comparison p {
  margin: 0 0 12px;
  font-size: clamp(1.2rem, 2vw, 1.55rem);
  font-weight: 800;
}

.comparison span {
  display: block;
  color: rgba(255, 248, 237, 0.72);
}

.comparison .is-highlighted span {
  color: var(--ink-soft);
}

.edge-section h2 {
  line-height: 1.12;
}

.team-section {
  background:
    radial-gradient(circle at 14% 10%, rgba(217, 144, 60, 0.16), rgba(217, 144, 60, 0) 28%),
    #fffaf2;
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  margin-top: clamp(44px, 6vw, 74px);
}

.team-card {
  min-height: 340px;
  padding: clamp(24px, 3vw, 32px);
  background: rgba(255, 255, 255, 0.64);
}

.member-avatar {
  display: grid;
  width: 58px;
  height: 58px;
  margin-bottom: 34px;
  place-items: center;
  border: 1px solid rgba(155, 90, 32, 0.2);
  border-radius: 50%;
  background: linear-gradient(145deg, #fff8ed, #e9b96f);
  color: var(--warm-deep);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.35rem;
  font-weight: 700;
  box-shadow: 0 16px 36px rgba(100, 61, 23, 0.12);
}

.team-card h3 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(1.25rem, 1.8vw, 1.58rem);
  line-height: 1.12;
}

.member-role {
  margin: 10px 0 22px;
  color: var(--warm-deep);
  font-size: 0.88rem;
  font-weight: 850;
  line-height: 1.4;
}

.team-card p:last-child {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.72;
}

.timeline-section {
  background:
    radial-gradient(circle at 76% 18%, rgba(255, 204, 127, 0.28), rgba(255, 204, 127, 0) 28%),
    var(--paper);
}

.timeline-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(340px, 0.72fr);
  gap: clamp(34px, 6vw, 82px);
  align-items: start;
}

.timeline-track {
  position: relative;
  display: grid;
  gap: 10px;
  margin-top: 34px;
  padding-left: 20px;
}

.timeline-track::before {
  content: "";
  position: absolute;
  top: 22px;
  bottom: 22px;
  left: 5px;
  width: 2px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(217, 144, 60, 0.85), rgba(217, 144, 60, 0.08));
}

.timeline-item {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  min-height: 48px;
  padding: 10px 14px;
  border: 1px solid rgba(97, 65, 33, 0.13);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.42);
  color: var(--ink-soft);
  font-size: 0.95rem;
  font-weight: 760;
  text-align: left;
  cursor: pointer;
  transition:
    transform 180ms ease,
    background 180ms ease,
    border-color 180ms ease,
    box-shadow 180ms ease,
    color 180ms ease;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -21px;
  width: 12px;
  height: 12px;
  border: 2px solid var(--paper);
  border-radius: 50%;
  background: #dfb16d;
  box-shadow: 0 0 0 1px rgba(155, 90, 32, 0.24);
}

.timeline-item span {
  min-width: 76px;
  color: var(--warm-deep);
  font-size: 0.78rem;
  font-weight: 900;
}

.timeline-item:hover,
.timeline-item.is-active {
  transform: translateX(4px);
  border-color: rgba(155, 90, 32, 0.34);
  background: #fff1dd;
  color: var(--ink);
  box-shadow: 0 14px 34px rgba(100, 61, 23, 0.1);
}

.timeline-item.is-active::before {
  background: var(--ink);
}

.milestone-card {
  position: sticky;
  top: 96px;
  min-height: 440px;
  padding: clamp(30px, 4vw, 44px);
  background:
    linear-gradient(145deg, rgba(255, 248, 237, 0.94), rgba(255, 239, 214, 0.86)),
    url("assets/hero-study.png") 62% 54% / 160% auto no-repeat;
  overflow: hidden;
}

.milestone-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255, 248, 237, 0.94), rgba(255, 248, 237, 0.76));
}

.milestone-card > * {
  position: relative;
  z-index: 1;
}

.milestone-card p {
  margin: 0 0 46px;
  color: var(--warm-deep);
  font-size: 0.9rem;
  font-weight: 900;
  line-height: 1.4;
  text-transform: uppercase;
}

.milestone-card h3 {
  margin: 0;
  max-width: 440px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.3rem, 4vw, 4rem);
  font-weight: 500;
  line-height: 1.05;
}

.milestone-card span {
  display: block;
  max-width: 420px;
  margin-top: 24px;
  color: var(--ink-soft);
  font-size: 1.04rem;
  line-height: 1.72;
}

.milestone-card.is-changing {
  animation: card-pulse 360ms ease;
}

.closing-section {
  display: grid;
  min-height: 64vh;
  place-items: center;
  padding: clamp(86px, 12vw, 150px) clamp(20px, 5vw, 72px);
  background:
    linear-gradient(180deg, rgba(255, 248, 237, 0.72), var(--paper) 70%),
    url("assets/home-tutor.png") center / cover no-repeat;
  text-align: center;
}

.closing-content {
  width: min(900px, 100%);
}

.closing-content h2 {
  margin: 0 auto;
}

.closing-content p {
  margin-left: auto;
  margin-right: auto;
}

.closing-content .primary-button {
  margin-top: 32px;
  background: var(--ink);
  color: #fff8ed;
}

.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition:
    opacity 700ms ease,
    transform 700ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 980px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .desktop-nav,
  .header-action {
    display: none;
  }

  .menu-button {
    display: block;
  }

  .hero {
    min-height: 100svh;
    background:
      linear-gradient(180deg, rgba(255, 248, 237, 0.96) 0%, rgba(255, 241, 224, 0.92) 45%, rgba(255, 236, 205, 0.54) 74%, rgba(255, 248, 237, 0.94) 100%),
      url("assets/hero-study.png") 62% center / cover no-repeat;
  }

  .hero-content {
    align-self: start;
    width: min(650px, calc(100% - 40px));
    margin: 0 auto;
    padding-top: 136px;
  }

  .split-layout,
  .edge-layout,
  .loop-layout,
  .model-layout,
  .timeline-layout,
  .solution-system {
    grid-template-columns: 1fr;
  }

  .solution-system {
    gap: 18px;
  }

  .agent-core {
    min-height: 132px;
  }

  .agent-core::before,
  .agent-core::after {
    display: none;
  }

  .loop-card {
    position: relative;
    top: 0;
    min-height: 460px;
  }

  .milestone-card {
    position: relative;
    top: 0;
    min-height: 360px;
  }

  .hardware-list {
    grid-template-columns: 1fr;
  }

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

@media (min-width: 981px) {
  body.menu-open {
    overflow: auto;
  }

  .mobile-nav {
    display: none;
  }
}

@media (max-width: 680px) {
  .site-header {
    min-height: 66px;
    padding: 12px 16px;
  }

  .brand {
    gap: 10px;
    max-width: calc(100vw - 82px);
    font-size: 0.88rem;
  }

  .brand-mark {
    width: 38px;
    height: 38px;
    border-radius: 13px;
  }

  .mobile-nav {
    top: 68px;
  }

  .hero-content {
    width: calc(100% - 32px);
    padding-top: 112px;
  }

  .company-line {
    margin-bottom: 16px;
  }

  .hero h1 {
    font-size: clamp(3.25rem, 17vw, 4.65rem);
  }

  .hero-lede {
    max-width: 20ch;
    font-size: clamp(1.62rem, 8vw, 2.45rem);
  }

  .hero-copy {
    max-width: 34ch;
    font-size: 1rem;
  }

  .hero-actions {
    display: grid;
    grid-template-columns: 1fr;
    max-width: 280px;
  }

  .primary-button,
  .secondary-button {
    width: 100%;
  }

  .scroll-cue {
    display: none;
  }

  .section {
    padding: 72px 16px;
  }

  .section h2,
  .closing-content h2 {
    font-size: clamp(2.25rem, 12vw, 3.3rem);
  }

  .problem-grid article {
    grid-template-columns: 1fr;
  }

  .problem-grid span {
    grid-row: auto;
  }

  .device-panel {
    grid-template-rows: 214px 1fr;
  }

  .loop-step {
    align-items: flex-start;
    min-height: 60px;
  }

  .loop-card {
    min-height: 500px;
  }

  .loop-card-top {
    margin-bottom: 38px;
  }

  .closing-section {
    min-height: 560px;
  }

  .team-grid {
    grid-template-columns: 1fr;
  }

  .team-card {
    min-height: auto;
  }

  .timeline-track {
    padding-left: 16px;
  }

  .timeline-item {
    align-items: flex-start;
    min-height: 58px;
    flex-direction: column;
    gap: 3px;
  }

  .timeline-item span {
    min-width: 0;
  }

  .milestone-card h3 {
    font-size: clamp(2.1rem, 11vw, 3rem);
  }
}

@media (max-width: 390px) {
  .brand span:last-child {
    max-width: 176px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .hero-copy {
    max-width: 31ch;
  }
}