:root {
  --bg: #071014;
  --bg-2: #0d191f;
  --panel: rgba(255, 255, 255, 0.055);
  --line: rgba(216, 234, 241, 0.15);
  --text: #f4fbff;
  --muted: #a8bbc5;
  --soft: #6f8793;
  --cyan: #00c4d8;
  --blue: #1b74ff;
  --gold: #d8b36a;
  --max: 1180px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--bg);
}

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 82% 8%, rgba(0, 196, 216, 0.16), transparent 30rem),
    radial-gradient(circle at 12% 92%, rgba(27, 116, 255, 0.14), transparent 28rem),
    linear-gradient(180deg, #050b0f 0%, var(--bg) 36%, #081117 100%);
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Pretendard", "Segoe UI", sans-serif;
  line-height: 1.65;
  word-break: keep-all;
  overflow-x: hidden;
}

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

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  color: #9fe9f2;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 30;
  padding: 10px 14px;
  background: var(--cyan);
  color: #031014;
  font-weight: 800;
}

.skip-link:focus {
  top: 12px;
}

.inline-link {
  color: var(--cyan);
  border-bottom: 1px solid rgba(0, 196, 216, 0.4);
}

/* ---------- Header ---------- */

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: auto;
  width: 100%;
  max-width: 100dvw;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(5, 11, 15, 0.76);
  backdrop-filter: blur(18px);
}

.nav {
  width: min(var(--max), calc(100% - 48px));
  height: 76px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand img {
  width: 44px;
  height: 44px;
  object-fit: contain;
}

.brand span {
  display: block;
  font-weight: 800;
  letter-spacing: 0;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

.nav-links a {
  transition: color 180ms ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text);
}

.nav-cta {
  padding: 9px 15px;
  border: 1px solid rgba(0, 196, 216, 0.48);
  color: #d8fbff;
}

main {
  padding-top: 76px;
}

.section {
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto;
}

/* ---------- Hero (home) ---------- */

.hero {
  min-height: calc(86svh - 76px);
  display: grid;
  grid-template-columns: minmax(0, 0.94fr) minmax(420px, 0.86fr);
  align-items: center;
  gap: 72px;
  padding: 56px 0 52px;
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--cyan);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
}

h1 {
  margin: 0;
  max-width: 780px;
  font-size: clamp(46px, 6.2vw, 84px);
  line-height: 0.98;
  letter-spacing: 0;
}

.hero-headline {
  margin: 26px 0 0;
  max-width: 680px;
  font-size: clamp(22px, 2.2vw, 30px);
  line-height: 1.35;
  font-weight: 800;
}

.hero-copy {
  max-width: 650px;
  margin: 22px 0 0;
  color: #c2d3dc;
  font-size: clamp(17px, 1.5vw, 20px);
  line-height: 1.78;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid var(--line);
  font-weight: 800;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
  border-color: rgba(0, 196, 216, 0.6);
}

.button.primary {
  border-color: transparent;
  color: #031014;
  background: linear-gradient(135deg, var(--cyan), #7df4ff);
}

.visual {
  position: relative;
  min-height: 640px;
  isolation: isolate;
}

.visual::before {
  content: "";
  position: absolute;
  inset: 6% -8% 4% 6%;
  background:
    linear-gradient(90deg, rgba(0, 196, 216, 0.11) 1px, transparent 1px),
    linear-gradient(0deg, rgba(0, 196, 216, 0.10) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(circle at center, #000 28%, transparent 72%);
  opacity: 0.9;
  z-index: -2;
}

.visual::after {
  content: "";
  position: absolute;
  inset: 12% 4% 12% 10%;
  background: radial-gradient(circle, rgba(0, 196, 216, 0.28), transparent 64%);
  filter: blur(30px);
  z-index: -3;
}

.library-stack {
  position: absolute;
  right: 2%;
  top: 7%;
  width: 78%;
  border: 1px solid var(--line);
  background: linear-gradient(145deg, rgba(255,255,255,0.09), rgba(255,255,255,0.025));
  box-shadow: 0 26px 80px rgba(0, 0, 0, 0.38);
  padding: 28px 28px 104px;
  overflow: hidden;
}

.library-stack::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(115deg, transparent 0 42%, rgba(0, 196, 216, 0.12) 43%, transparent 58%),
    radial-gradient(circle at 18% 16%, rgba(216, 179, 106, 0.14), transparent 18rem);
  pointer-events: none;
}

.stack-head {
  position: relative;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
}

.status-dot {
  width: 8px;
  height: 8px;
  display: inline-block;
  margin-right: 8px;
  border-radius: 999px;
  background: var(--cyan);
  box-shadow: 0 0 18px var(--cyan);
}

.search-line {
  position: relative;
  margin-top: 42px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.search-line strong {
  display: block;
  font-size: 28px;
  letter-spacing: 0;
}

.search-line span {
  color: var(--muted);
  font-size: 15px;
}

.shelves {
  position: relative;
  display: grid;
  gap: 14px;
  margin-top: 34px;
}

.shelf {
  display: grid;
  grid-template-columns: 110px 1fr auto;
  align-items: center;
  gap: 18px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(216, 234, 241, 0.1);
}

.shelf b {
  color: #e9f8fd;
  font-size: 15px;
}

.bar {
  height: 8px;
  background: linear-gradient(90deg, rgba(0, 196, 216, 0.88), rgba(27, 116, 255, 0.24));
}

.shelf span {
  color: var(--gold);
  font-size: 13px;
  font-weight: 800;
}

.floating-card {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 285px;
  border: 1px solid rgba(0, 196, 216, 0.32);
  background: rgba(4, 13, 18, 0.88);
  padding: 20px;
  box-shadow: 0 22px 60px rgba(0, 0, 0, 0.42);
}

.floating-card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.floating-card strong {
  display: block;
  margin-bottom: 8px;
  color: var(--text);
  font-size: 20px;
  letter-spacing: 0;
}

/* ---------- Proof row ---------- */

.proof {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.proof > * {
  display: block;
  padding: 28px 24px;
  border-right: 1px solid var(--line);
  transition: background 180ms ease;
}

.proof > *:last-child {
  border-right: 0;
}

.proof a:hover {
  background: rgba(0, 196, 216, 0.06);
}

.proof a:hover b {
  color: #9fe9f2;
}

.proof b {
  display: block;
  color: var(--text);
  font-size: 18px;
  letter-spacing: 0;
}

.proof span {
  display: block;
  margin-top: 6px;
  color: var(--soft);
  font-size: 14px;
}

/* ---------- Content sections ---------- */

.content-section {
  padding: 116px 0;
}

.intro {
  display: grid;
  grid-template-columns: 0.88fr 1fr;
  gap: 82px;
  align-items: start;
}

h2 {
  margin: 0;
  font-size: clamp(34px, 4vw, 56px);
  line-height: 1.08;
  letter-spacing: 0;
}

.lead {
  margin: 0;
  color: #c0d1da;
  font-size: 20px;
}

.capability-list {
  display: grid;
  gap: 0;
  margin-top: 42px;
  border-top: 1px solid var(--line);
}

.capability {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 32px;
  padding: 25px 0;
  border-bottom: 1px solid var(--line);
}

.capability b {
  color: var(--cyan);
  font-size: 15px;
}

.capability p {
  margin: 0;
  color: var(--muted);
}

.services {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  margin-top: 56px;
  background: var(--line);
  border: 1px solid var(--line);
}

.service {
  min-height: 260px;
  padding: 34px;
  background: rgba(7, 16, 20, 0.96);
  transition: background 180ms ease;
}

.service:hover {
  background: rgba(13, 25, 31, 0.98);
}

.service small {
  color: var(--gold);
  font-weight: 900;
  letter-spacing: 0;
}

.service h3 {
  margin: 44px 0 12px;
  font-size: 25px;
  line-height: 1.2;
  letter-spacing: 0;
}

.service p {
  margin: 0;
  color: var(--muted);
}

.process {
  background: linear-gradient(180deg, rgba(255,255,255,0.035), rgba(255,255,255,0.015));
  border-block: 1px solid var(--line);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin-top: 54px;
  background: var(--line);
  border: 1px solid var(--line);
}

.step {
  padding: 28px;
  background: var(--bg-2);
}

.step span {
  color: var(--cyan);
  font-weight: 900;
}

.step b {
  display: block;
  margin: 34px 0 10px;
  font-size: 22px;
  letter-spacing: 0;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.history-contact {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: start;
}

.timeline {
  margin-top: 38px;
  border-top: 1px solid var(--line);
}

.timeline p {
  display: grid;
  grid-template-columns: 128px 1fr;
  gap: 24px;
  margin: 0;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
}

.timeline b {
  color: var(--gold);
}

.contact-panel {
  padding: 36px;
  border: 1px solid rgba(0, 196, 216, 0.24);
  background: linear-gradient(145deg, rgba(0, 196, 216, 0.09), rgba(255, 255, 255, 0.025));
}

.contact-panel p {
  margin: 14px 0 0;
  color: var(--muted);
}

.contact-list {
  display: grid;
  gap: 16px;
  margin-top: 32px;
  color: #d5e8ef;
}

.contact-list a {
  color: var(--text);
  border-bottom: 1px solid rgba(0, 196, 216, 0.3);
}

/* ---------- Sub-page: head ---------- */

.page-head {
  max-width: 880px;
  padding: 96px 0 56px;
}

.page-head h1 {
  max-width: none;
  font-size: clamp(38px, 5vw, 66px);
  line-height: 1.06;
}

.page-head .lead {
  margin-top: 26px;
}

/* ---------- Sub-page: system map ---------- */

.system-map {
  margin: 48px 0 0;
  padding: 28px;
  border: 1px solid var(--line);
  background: var(--panel);
  overflow-x: auto;
}

.system-map svg {
  display: block;
  width: 100%;
  min-width: 760px;
  height: auto;
}

.system-map rect {
  fill: rgba(255, 255, 255, 0.045);
  stroke: rgba(216, 234, 241, 0.3);
  stroke-width: 1;
}

.system-map rect.accent {
  fill: rgba(0, 196, 216, 0.09);
  stroke: rgba(0, 196, 216, 0.6);
}

.system-map rect.gold {
  fill: rgba(216, 179, 106, 0.08);
  stroke: rgba(216, 179, 106, 0.55);
}

.system-map rect.chip {
  fill: rgba(0, 196, 216, 0.08);
  stroke: rgba(0, 196, 216, 0.35);
}

.system-map text {
  fill: #e9f8fd;
  font-size: 15px;
  font-weight: 700;
  font-family: inherit;
}

.system-map text.sub {
  fill: #a8bbc5;
  font-size: 13px;
  font-weight: 500;
}

.system-map text.chip-text {
  font-size: 13px;
}

.system-map line {
  stroke: rgba(0, 196, 216, 0.5);
  stroke-width: 1.5;
}

.system-map figcaption {
  margin-top: 18px;
  color: var(--soft);
  font-size: 14px;
}

/* ---------- Sub-page: concept cards ---------- */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.section-lead {
  max-width: 760px;
  margin-top: 22px;
  font-size: 17px;
  color: var(--muted);
}

.concepts {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  margin-top: 48px;
  background: var(--line);
  border: 1px solid var(--line);
}

.concept {
  padding: 34px;
  background: rgba(7, 16, 20, 0.96);
}

.concept.wide {
  grid-column: 1 / -1;
}

.concept small {
  color: var(--gold);
  font-weight: 900;
  letter-spacing: 0;
}

.concept h3 {
  margin: 18px 0 10px;
  font-size: 23px;
  line-height: 1.25;
  letter-spacing: 0;
}

.concept .summary {
  margin: 0;
  color: var(--muted);
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.tags li {
  padding: 5px 10px;
  border: 1px solid rgba(0, 196, 216, 0.35);
  background: rgba(0, 196, 216, 0.06);
  color: #bfeef5;
  font-size: 13px;
  font-weight: 700;
  line-height: 1.4;
}

details.more {
  margin-top: 22px;
  border-top: 1px solid var(--line);
}

details.more summary {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 0;
  list-style: none;
  cursor: pointer;
  color: var(--cyan);
  font-size: 14px;
  font-weight: 800;
}

details.more summary::-webkit-details-marker {
  display: none;
}

details.more summary::after {
  content: "+";
  margin-left: auto;
  font-size: 20px;
  line-height: 1;
}

details.more[open] summary::after {
  content: "\2013";
}

details.more .more-body {
  padding: 4px 0 10px;
}

details.more .more-body > p {
  margin: 0 0 18px;
  color: var(--muted);
  font-size: 16px;
}

.points {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.points li {
  position: relative;
  padding: 14px 0 14px 32px;
  border-bottom: 1px solid var(--line);
  color: #d5e8ef;
  font-size: 15px;
}

.points li::before {
  content: "\2014";
  position: absolute;
  left: 0;
  top: 14px;
  color: var(--cyan);
  font-weight: 800;
}

.stack-block {
  padding: 0 0 96px;
}

.stack-table {
  width: 100%;
  margin-top: 36px;
  border-collapse: collapse;
  font-size: 15px;
}

.stack-table th,
.stack-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.stack-table th {
  width: 160px;
  color: var(--cyan);
  font-weight: 800;
  white-space: nowrap;
}

.stack-table td {
  color: var(--muted);
}

/* ---------- Sub-page: case cards ---------- */

.cases {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  align-items: start;
  gap: 24px;
  margin-top: 48px;
}

.case {
  padding: 34px;
  border: 1px solid var(--line);
  background: rgba(7, 16, 20, 0.96);
}

.case small {
  color: var(--gold);
  font-weight: 900;
}

.case h3 {
  margin: 14px 0 18px;
  font-size: 23px;
  line-height: 1.25;
  letter-spacing: 0;
}

.case .problem,
.case .solution {
  margin: 0 0 12px;
  color: #d5e8ef;
  font-size: 15px;
}

.case .solution {
  color: var(--muted);
}

.case .problem b,
.case .solution b {
  display: inline-block;
  margin-right: 10px;
  color: var(--gold);
  font-size: 12px;
  font-weight: 900;
  vertical-align: 1px;
}

.case dl {
  margin: 0;
}

.case .row {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.case dt {
  padding-top: 2px;
  color: var(--cyan);
  font-size: 14px;
  font-weight: 800;
}

.case dd {
  margin: 0;
  color: var(--muted);
}

.cta-band {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 32px;
  padding: 72px 0;
  border-top: 1px solid var(--line);
}

.cta-band h2 {
  font-size: clamp(26px, 3vw, 40px);
}

.note {
  margin: 0;
  color: var(--soft);
  font-size: 14px;
}

/* ---------- Footer ---------- */

footer {
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto;
  padding: 34px 0 54px;
  display: flex;
  justify-content: space-between;
  gap: 24px;
  border-top: 1px solid var(--line);
  color: var(--soft);
  font-size: 14px;
}

footer a {
  color: var(--muted);
}

/* ---------- Responsive ---------- */

@media (max-width: 960px) {
  .nav {
    width: min(var(--max), calc(100% - 32px));
  }

  .nav-links {
    gap: 18px;
  }

  .nav-links a:not(.nav-cta):not(.nav-page) {
    display: none;
  }

  .section,
  footer {
    width: min(var(--max), calc(100% - 32px));
  }

  .hero,
  .intro,
  .history-contact {
    grid-template-columns: 1fr;
  }

  .hero {
    gap: 44px;
    min-height: auto;
    padding-top: 64px;
  }

  .visual {
    min-height: 500px;
  }

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

  .services,
  .concepts,
  .cases {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 620px) {
  .nav {
    height: 68px;
  }

  .nav-links {
    gap: 14px;
    font-size: 13px;
  }

  .brand span {
    display: none;
  }

  .brand img {
    width: 38px;
    height: 38px;
  }

  .nav-cta {
    padding: 8px 12px;
    font-size: 13px;
  }

  main {
    padding-top: 68px;
  }

  h1 {
    font-size: 40px;
    line-height: 1.08;
  }

  .hero {
    padding: 42px 0 42px;
    gap: 30px;
  }

  .hero-copy {
    font-size: 17px;
    line-height: 1.72;
  }

  .hero-actions {
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .visual {
    min-height: auto;
  }

  .visual::before {
    inset: 6% 0 4% 0;
  }

  .library-stack {
    position: relative;
    top: auto;
    width: 92%;
    right: auto;
    margin-left: auto;
    padding: 20px;
    min-height: 350px;
  }

  .shelf {
    grid-template-columns: 90px 1fr auto;
  }

  .floating-card {
    position: relative;
    left: auto;
    bottom: auto;
    width: min(100%, 320px);
    margin-top: -34px;
  }

  .proof,
  .steps {
    grid-template-columns: 1fr;
  }

  .proof > * {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .proof > *:last-child {
    border-bottom: 0;
  }

  .capability,
  .timeline p,
  .case .row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .content-section {
    padding: 82px 0;
  }

  .page-head {
    padding: 64px 0 40px;
  }

  .page-head h1 {
    font-size: 34px;
  }

  .system-map {
    padding: 16px;
  }

  .stack-table th {
    width: auto;
  }

  .stack-table th,
  .stack-table td {
    padding: 12px 10px;
  }

  .case,
  .concept {
    padding: 24px;
  }

  .cta-band {
    padding: 56px 0;
  }

  .cta-band .button {
    width: 100%;
  }

  footer {
    flex-direction: column;
  }
}