/* Tokens */
:root {
  --color-bg: #f3f9ff;
  --color-surface: rgba(230, 243, 255, .62);
  --color-surface-raised: rgba(255, 255, 255, .82);
  --color-surface-strong: rgba(255, 255, 255, .94);
  --color-grid: rgba(14, 116, 144, .09);
  --color-border: rgba(15, 23, 42, .14);
  --color-border-strong: rgba(15, 70, 199, .26);
  --color-accent: #0f46c7;
  --color-accent-muted: #075985;
  --color-accent-bright: #0891b2;
  --color-accent-hot: #10b981;
  --color-accent-soft: rgba(8, 145, 178, .12);
  --color-accent-soft-hover: rgba(16, 185, 129, .18);
  --color-glow: rgba(14, 165, 233, .18);
  --color-nav-bg: rgba(243, 249, 255, .84);
  --color-nav-fade: rgba(243, 249, 255, .98);
  --color-text: #0f172a;
  --color-text-muted: #334155;
  --color-on-accent: #f8fbff;

  --font-body: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Apple SD Gothic Neo', 'Malgun Gothic', sans-serif;
  --font-display: 'AppleMyungjo', 'Batang', 'NanumMyeongjo', Georgia, 'Times New Roman', serif;
  --font-mono: ui-monospace, SFMono-Regular, Consolas, 'Liberation Mono', 'Apple SD Gothic Neo', 'Malgun Gothic', monospace;

  --space-2xs: .2rem;
  --space-xs: .35rem;
  --space-sm: .5rem;
  --space-md: .75rem;
  --space-lg: 1rem;
  --space-xl: 1.5rem;
  --space-2xl: 2rem;
  --space-3xl: 3rem;
  --space-section: 6rem;
  --gutter: clamp(1.5rem, 5vw, 4rem);
  --max-width: 1200px;

  --radius-xs: 2px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --line: 1px solid var(--color-border);
  --divider-size: 1.5px;
  --shadow-frame: 0 22px 52px rgba(8, 47, 73, .14);
  --shadow-card: 0 18px 42px rgba(8, 47, 73, .2);
  --shadow-card-strong: 0 22px 54px rgba(8, 47, 73, .24);
  --shadow-soft: inset 0 1px 0 rgba(255, 255, 255, .45);
  --surface-panel:
    linear-gradient(180deg, rgba(255, 255, 255, .38), rgba(255, 255, 255, .14)),
    var(--color-surface);
  --surface-panel-frame:
    linear-gradient(135deg, rgba(255, 255, 255, .26), rgba(255, 255, 255, .08)),
    rgba(15, 23, 42, .12);
  --surface-panel-shadow: var(--shadow-frame), inset 0 1px 0 rgba(255, 255, 255, .34);

  --motion-fast: .18s ease;
  --motion-slow: .52s cubic-bezier(.2, .9, .2, 1);
  --motion-card: background var(--motion-fast), box-shadow var(--motion-fast), border-color var(--motion-fast), transform var(--motion-fast);
  --motion-control: background var(--motion-fast), border-color var(--motion-fast), box-shadow var(--motion-fast), color var(--motion-fast), transform var(--motion-fast);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
a { color: inherit; text-decoration: none; }
strong { font-weight: 600; }

/* Base */
body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.7;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(115deg, transparent 0 34%, rgba(8, 145, 178, .11) 34% 34.35%, transparent 34.35% 100%),
    linear-gradient(115deg, transparent 0 63%, rgba(16, 185, 129, .1) 63% 63.3%, transparent 63.3% 100%),
    linear-gradient(var(--color-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-grid) 1px, transparent 1px);
  background-size: 360px 360px, 460px 460px, 52px 52px, 52px 52px;
  animation: grid-drift 11s linear infinite;
  opacity: .95;
  pointer-events: none;
  z-index: 0;
}

body::after {
  content: '';
  position: fixed;
  inset: 0;
  background:
    linear-gradient(125deg, transparent 0 12%, rgba(14, 165, 233, .16) 12% 12.35%, transparent 12.35% 100%),
    linear-gradient(125deg, transparent 0 78%, rgba(16, 185, 129, .14) 78% 78.35%, transparent 78.35% 100%);
  animation: energy-sweep 7s ease-in-out infinite alternate;
  pointer-events: none;
  z-index: 0;
}

/* Layout primitives */
.shell {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gutter);
  position: relative;
  z-index: 1;
}

.section {
  padding: var(--space-section) 0;
  isolation: isolate;
  position: relative;
}

.band {
  background:
    linear-gradient(135deg, rgba(255, 255, 255, .46), transparent 28%),
    linear-gradient(118deg, transparent 0 62%, rgba(14, 165, 233, .14) 62% 63.1%, transparent 63.1% 100%),
    linear-gradient(180deg, rgba(255, 255, 255, .34), rgba(230, 243, 255, .22)),
    var(--color-surface);
  border-top: var(--line);
  border-bottom: var(--line);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .36), inset 0 -1px 0 rgba(15, 70, 199, .05);
  overflow: hidden;
}

.band::before {
  background:
    radial-gradient(circle at 18% 24%, var(--color-glow) 0, transparent 28%),
    radial-gradient(circle at 82% 72%, rgba(16, 185, 129, .14) 0, transparent 24%);
  content: '';
  inset: 0;
  opacity: .9;
  pointer-events: none;
  position: absolute;
  z-index: 0;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}

.cluster {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
}

.frame,
.number-list,
.info-list {
  border: var(--line);
  border-radius: var(--radius-sm);
  box-shadow: var(--surface-panel-shadow);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  overflow: hidden;
}

.frame {
  background: var(--surface-panel-frame);
  gap: var(--divider-size);
}

.card {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .52), rgba(255, 255, 255, .16)),
    var(--color-surface);
  box-shadow: var(--shadow-soft);
  isolation: isolate;
  overflow: hidden;
  position: relative;
}

.raised {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .82), rgba(255, 255, 255, .28)),
    var(--color-surface-raised);
}

.interactive {
  --interactive-background:
    linear-gradient(180deg, rgba(255, 255, 255, .82), rgba(255, 255, 255, .28)),
    var(--color-surface-raised);
  --interactive-shadow: var(--shadow-card), inset 0 1px 0 rgba(255, 255, 255, .6);
  --interactive-transform: none;
  transition: var(--motion-card);
}

.interactive:hover {
  background: var(--interactive-background);
  box-shadow: var(--interactive-shadow);
  transform: var(--interactive-transform);
}

.card::before {
  background:
    linear-gradient(135deg, rgba(255, 255, 255, .28), transparent 26%),
    linear-gradient(125deg, transparent 0 70%, rgba(8, 145, 178, .08) 70% 72%, transparent 72% 100%);
  content: '';
  inset: 0;
  pointer-events: none;
  position: absolute;
  z-index: 0;
}

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

.list-stack {
  display: flex;
  flex-direction: column;
}

.align-right { text-align: right; }

/* Text primitives */
.eyebrow,
.list-index,
.mono-note,
.empty-state,
.info-key,
.footer-meta,
.footer-legal {
  font-family: var(--font-mono);
}

.eyebrow {
  color: var(--color-accent);
  font-size: .76rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.eyebrow-line {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  margin-bottom: var(--space-2xl);
}

.eyebrow-line::after {
  background: var(--color-border);
  content: '';
  flex: 1;
  height: 1px;
}

.display-title,
.section-title {
  font-family: var(--font-display);
  line-height: 1.15;
}

.display-title {
  font-size: clamp(3rem, 8vw, 7rem);
  line-height: 1;
  letter-spacing: -.02em;
  margin-bottom: 1.25rem;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 3rem);
  margin-top: 0;
}

.section-heading {
  display: grid;
  gap: var(--space-md);
  margin-bottom: 3.5rem;
}

.flow {
  color: var(--color-text);
  font-size: 1.05rem;
  line-height: 1.85;
}

.flow p + p { margin-top: 1.25rem; }

.small-copy {
  color: var(--color-text-muted);
  font-size: .95rem;
  line-height: 1.8;
}

.accent-text { color: var(--color-accent-muted); }
.dim-text { opacity: .68; }

/* Control primitives */
.chip {
  background: rgba(255, 255, 255, .34);
  border: var(--line);
  border-radius: var(--radius-xs);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .34);
  color: var(--color-text-muted);
  cursor: pointer;
  font-family: var(--font-body);
  font-weight: 600;
  letter-spacing: 0;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  transition: var(--motion-control);
}

.chip:hover {
  background: rgba(255, 255, 255, .56);
  border-color: var(--color-border-strong);
  box-shadow: 0 10px 24px rgba(8, 47, 73, .12), inset 0 1px 0 rgba(255, 255, 255, .52);
  color: var(--color-accent);
  transform: translateY(-2px);
}

.chip.active {
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-bright));
  border-color: var(--color-accent);
  box-shadow: 0 12px 28px rgba(15, 70, 199, .22);
  color: var(--color-on-accent);
}

/* Animation primitives */
.reveal {
  opacity: 0;
  transform: translateY(36px) skewY(.8deg);
  transition: opacity var(--motion-slow), transform var(--motion-slow);
}

.in-view {
  opacity: 1;
  transform: translateY(0) skewY(0);
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: .25; }
}

@keyframes pulse {
  0%, 100% { opacity: .45; transform: translate3d(-4%, -3%, 0) rotate(-12deg) scaleX(1); }
  50% { opacity: .95; transform: translate3d(-12%, 8%, 0) rotate(-12deg) scaleX(1.12); }
}

@keyframes grid-drift {
  from { background-position: 0 0, 0 0, 0 0, 0 0; }
  to { background-position: 360px 360px, -460px 460px, 52px 52px, -52px 52px; }
}

@keyframes energy-sweep {
  from { opacity: .35; transform: translate3d(-3%, -2%, 0); }
  to { opacity: .9; transform: translate3d(4%, 3%, 0); }
}

@keyframes notice-enter {
  from { opacity: 0; transform: translateX(-14px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes hero-enter {
  from { opacity: 0; transform: translateY(28px) scale(.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* Navigation */
.topbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  background: var(--color-nav-bg);
  border-bottom: var(--line);
}

.nav-layout {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.brand,
.footer-brand {
  color: var(--color-accent-muted);
  font-family: var(--font-display);
}

.brand {
  font-size: 1.25rem;
  letter-spacing: .04em;
}

.nav-scroll { display: flex; }
.nav-arrow { display: none; }
.nav-links { display: flex; gap: var(--space-2xl); }

.nav-links a {
  color: var(--color-text-muted);
  font-size: .82rem;
  font-weight: 600;
  position: relative;
  transition: color var(--motion-fast), transform var(--motion-fast);
}

.nav-links a::after {
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-hot));
  bottom: -.35rem;
  content: '';
  height: 2px;
  left: 0;
  position: absolute;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--motion-fast);
  width: 100%;
}

.nav-links a:hover {
  color: var(--color-accent);
  transform: translateY(-1px);
}

.nav-links a:hover::after { transform: scaleX(1); }

.notice-dot {
  display: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
  margin-left: .4rem;
  vertical-align: middle;
  animation: blink 2s ease-in-out infinite;
}

.visible { display: inline-block; }

/* Hero */
.hero {
  min-height: 100svh;
  display: grid;
  place-content: center;
  padding: 6rem var(--gutter) 4rem;
  position: relative;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: -18%; left: 18%;
  width: 1100px; height: 520px;
  background:
    linear-gradient(105deg, transparent 0 18%, rgba(14, 165, 233, .36) 18% 20%, transparent 20% 34%, rgba(16, 185, 129, .24) 34% 35.5%, transparent 35.5% 100%);
  pointer-events: none;
  animation: pulse 4.8s ease-in-out infinite;
}

.hero .shell {
  max-width: 900px;
  animation: hero-enter .62s cubic-bezier(.2, .9, .2, 1) both;
}

.hero .display-title em {
  color: var(--color-accent-muted);
  font-style: italic;
}

.lead {
  color: var(--color-text-muted);
  font-size: clamp(1rem, 1.8vw, 1.2rem);
  line-height: 1.9;
  max-width: 560px;
  margin-bottom: var(--space-3xl);
}

.hero .chip {
  background: rgba(255, 255, 255, .72);
  font-size: .82rem;
  padding: .35rem .85rem;
}

.hero .chip:hover {
  background: var(--color-surface-raised);
  transform: translateY(-3px);
}

/* Lists */
.number-list,
.info-list {
  background: var(--surface-panel);
  padding: 0 1.5rem;
}

.number-list { list-style: none; }

.number-list li,
.info-row {
  display: flex;
}

.number-list li + li,
.info-list .info-row + .info-row {
  border-top: var(--line);
}

.number-list li {
  gap: var(--space-lg);
  align-items: flex-start;
  padding: 1.1rem 0;
  font-size: .95rem;
}

.list-index {
  color: var(--color-accent);
  font-size: .78rem;
  min-width: 1.8rem;
  padding-top: .1rem;
}

/* Card grids */
.stage-grid,
.capability-grid {
  display: grid;
}

.stage-grid { grid-template-columns: repeat(3, 1fr); }
.capability-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.stage-card {
  --interactive-shadow: var(--shadow-card-strong);
  --interactive-transform: translateY(-12px) skewY(-.45deg);
  padding: 2.5rem 2rem;
}

.stage-card .eyebrow {
  display: inline-block;
  margin-bottom: var(--space-lg);
}

.stage-number {
  color: rgba(37, 99, 235, .12);
  font-family: var(--font-display);
  font-size: 5rem;
  line-height: 1;
  position: absolute;
  right: 1.5rem; top: 1rem;
  pointer-events: none;
}

.card:not(.stage-card) {
  padding: 1.6rem 1.8rem;
}

.capability-grid .card {
  --interactive-transform: translateY(-10px) skewY(-.35deg);
}

.card-title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: .3rem;
}

.stage-card .card-title {
  font-size: 1.15rem;
  margin-bottom: .75rem;
}

.card-kicker {
  color: var(--color-accent);
  font-size: .78rem;
  font-weight: 700;
  line-height: 1.5;
}

.card-copy {
  color: var(--color-text-muted);
  font-size: .9rem;
  line-height: 1.65;
  margin-top: .5rem;
}

.stage-card .card-copy {
  font-size: .95rem;
  line-height: 1.75;
  margin-top: 0;
}

.mono-note {
  color: var(--color-accent);
  display: inline-block;
  font-size: .78rem;
  letter-spacing: .06em;
  margin-top: var(--space-xl);
}

.icon-tile {
  align-items: center;
  background: var(--color-accent-soft);
  border-radius: var(--radius-md);
  display: inline-flex;
  font-size: 1.5rem;
  height: 2.4rem;
  justify-content: center;
  margin-bottom: var(--space-md);
  transition: background var(--motion-fast), transform var(--motion-fast);
  width: 2.4rem;
}

.interactive:hover .icon-tile {
  background: var(--color-accent-soft-hover);
  transform: translateY(-5px) rotate(-4deg) scale(1.06);
}

/* Info and notices */
.info-row {
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-lg);
  padding: 1rem 0;
}

.list-stack .info-row {
  align-items: center;
  padding: 1.2rem 1.8rem;
}

.info-key {
  color: var(--color-text-muted);
  font-size: .82rem;
  letter-spacing: .02em;
}

.info-value {
  font-size: .98rem;
  font-weight: 600;
  text-align: right;
}

.info-value a,
.quiet-link {
  border-bottom: var(--line);
  padding-bottom: 1px;
  transition: border-color var(--motion-fast), color var(--motion-fast);
}

.info-value a:hover,
.quiet-link:hover {
  border-color: var(--color-accent);
  color: var(--color-accent-muted);
}

.filters {
  margin-top: 1.75rem;
  margin-bottom: var(--space-2xl);
}

.filters .chip {
  font-size: .86rem;
  padding: .35rem .9rem;
}

.notice-item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: var(--space-xl);
  animation: notice-enter .32s ease both;
  transition: var(--motion-card);
}

.notice-item:hover {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .84), rgba(255, 255, 255, .24)),
    var(--color-surface-strong);
  box-shadow: inset 4px 0 0 var(--color-accent);
  transform: translateX(12px);
}

.notice-type {
  border: var(--line);
  border-radius: var(--radius-xs);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .04em;
  padding: .2rem .6rem;
  white-space: nowrap;
}

.notice-title {
  font-size: 1rem;
  font-weight: 700;
}

.notice-summary {
  color: var(--color-text-muted);
  font-size: .92rem;
  margin-top: .2rem;
}

.notice-date {
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: .78rem;
  white-space: nowrap;
}

.empty-state {
  color: var(--color-text-muted);
  font-size: .9rem;
  letter-spacing: .04em;
  line-height: 1.8;
  padding: 3.5rem 2rem;
  text-align: center;
}

/* Footer */
.site-footer {
  background:
    linear-gradient(135deg, rgba(255, 255, 255, .4), transparent 28%),
    linear-gradient(118deg, transparent 0 68%, rgba(14, 165, 233, .1) 68% 69.1%, transparent 69.1% 100%),
    linear-gradient(180deg, rgba(255, 255, 255, .28), rgba(230, 243, 255, .18)),
    var(--color-surface);
  border-top: var(--line);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .36);
  overflow: hidden;
  padding: 3rem var(--gutter);
  position: relative;
}

.site-footer::after {
  background:
    radial-gradient(circle at 14% 18%, rgba(14, 165, 233, .14), transparent 26%),
    radial-gradient(circle at 86% 82%, rgba(16, 185, 129, .1), transparent 22%);
  content: '';
  inset: 0;
  opacity: .85;
  pointer-events: none;
  position: absolute;
}

.footer-layout {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xl);
  justify-content: space-between;
  align-items: flex-start;
  position: relative;
  z-index: 1;
}

.footer-brand {
  font-size: 1.1rem;
  margin-bottom: var(--space-sm);
}

.footer-meta {
  color: var(--color-text-muted);
  font-size: .76rem;
  letter-spacing: .02em;
  line-height: 1.9;
}

.footer-legal {
  color: var(--color-text-muted);
  font-size: .72rem;
  line-height: 1.8;
  margin-top: var(--space-sm);
  opacity: .85;
}

/* Responsive */
@media (max-width: 1000px) {
  .capability-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 800px) {
  .split { grid-template-columns: 1fr; gap: var(--space-2xl); }
  .stage-grid,
  .capability-grid { grid-template-columns: 1fr; }
  .notice-item { grid-template-columns: 1fr; gap: var(--space-sm); }

  .nav-layout {
    align-items: stretch;
    flex-direction: column;
    height: auto;
    padding-top: .8rem;
    padding-bottom: .75rem;
  }

  .brand { line-height: 1; }

  .nav-scroll {
    margin-top: var(--space-md);
    position: relative;
  }

  .nav-arrow {
    align-items: center;
    appearance: none;
    background: transparent;
    border: 0;
    bottom: 0;
    cursor: pointer;
    display: flex;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    position: absolute;
    top: 0;
    transition: opacity var(--motion-fast);
    width: 2rem;
    z-index: 1;
  }

  .nav-arrow::before {
    border-color: var(--color-accent-muted);
    border-style: solid;
    border-width: 1.5px 1.5px 0 0;
    content: '';
    height: .42rem;
    opacity: .75;
    width: .42rem;
  }

  .nav-arrow-left {
    background: linear-gradient(90deg, var(--color-nav-fade), transparent);
    left: 0;
  }

  .nav-arrow-left::before { transform: rotate(-135deg); }

  .nav-arrow-right {
    background: linear-gradient(270deg, var(--color-nav-fade), transparent);
    right: 0;
  }

  .nav-arrow-right::before { transform: rotate(45deg); }

  .can-scroll-left .nav-arrow-left,
  .can-scroll-right .nav-arrow-right {
    opacity: 1;
    pointer-events: auto;
  }

  .nav-links {
    gap: 1.1rem;
    overflow-x: auto;
    padding: 0 2rem .1rem 0;
    scrollbar-width: none;
    white-space: nowrap;
  }

  .nav-links::-webkit-scrollbar { display: none; }

  .nav-links a {
    flex: 0 0 auto;
    font-size: .78rem;
  }

  .hero { padding-top: 8.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: .001ms !important;
  }
}