:root {
  --ink: #060d18;
  --ink-soft: #0b1b32;
  --slate: #1a2f4a;
  --sage: #8aa0b4;
  --pearl: #f5f0e1;
  --gold: #c4a574;
  --gold-deep: #9a7a4a;
  --gold-soft: rgba(196, 165, 116, 0.45);
  --teal: #5a8f9c;
  --teal-soft: rgba(90, 143, 156, 0.35);
  --copper: #c4896a;
  --copper-soft: rgba(196, 137, 106, 0.32);
  --steel: #6e8eb8;
  --steel-soft: rgba(110, 142, 184, 0.35);
  --line: rgba(245, 240, 225, 0.3);
  --line-soft: rgba(138, 160, 180, 0.38);
  --font-display: "Cormorant Garamond", Georgia, serif;
  --font-ui: "Outfit", system-ui, sans-serif;
  --field: 230px;
  --field-active: 310px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  min-height: 100%;
}

body {
  font-family: var(--font-ui);
  color: var(--pearl);
  background: var(--ink);
  overflow-x: hidden;
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto auto 1fr;
}

/* —— Istanbul architectural ribbon (PNG) —— */
.istanbul-ribbon {
  position: relative;
  z-index: 2;
  width: min(52rem, 78vw);
  height: clamp(130px, 16vw, 210px);
  margin: 0.75rem auto 0;
  overflow: hidden;
  background: #04152f;
  border-radius: 2px;
  animation: rise 1.2s var(--ease) both;
  mask-image: linear-gradient(
    90deg,
    transparent 0%,
    #000 12%,
    #000 88%,
    transparent 100%
  );
  -webkit-mask-image: linear-gradient(
    90deg,
    transparent 0%,
    #000 12%,
    #000 88%,
    transparent 100%
  );
  box-shadow: 0 0 0 1px rgba(216, 201, 165, 0.06);
}

.ribbon-track {
  display: flex;
  flex-wrap: nowrap;
  align-items: stretch;
  width: max-content;
  height: 100%;
  animation: ribbon-drift 110s linear infinite;
  will-change: transform;
}

.ribbon-img {
  display: block;
  height: 100%;
  width: auto;
  max-width: none;
  flex: 0 0 auto;
  object-fit: cover;
  object-position: center center;
  vertical-align: top;
  user-select: none;
  pointer-events: none;
}

@keyframes ribbon-drift {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

/* —— Atmosphere —— */
.atmosphere {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 55% 45% at 12% 55%, rgba(154, 122, 74, 0.14) 0%, transparent 55%),
    radial-gradient(ellipse 45% 40% at 38% 70%, rgba(90, 143, 156, 0.12) 0%, transparent 50%),
    radial-gradient(ellipse 45% 40% at 62% 45%, rgba(196, 137, 106, 0.1) 0%, transparent 50%),
    radial-gradient(ellipse 50% 42% at 88% 60%, rgba(110, 142, 184, 0.14) 0%, transparent 52%),
    radial-gradient(ellipse 80% 50% at 50% 18%, #1a3050 0%, transparent 60%),
    linear-gradient(165deg, #081420 0%, #060d18 40%, #0b1b32 100%);
}

.mist {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.4;
  animation: drift 18s ease-in-out infinite alternate;
}

.mist-a {
  width: 44vw;
  height: 44vw;
  top: 6%;
  left: 14%;
  background: rgba(90, 143, 156, 0.28);
}

.mist-b {
  width: 38vw;
  height: 38vw;
  bottom: 4%;
  right: 8%;
  background: rgba(196, 165, 116, 0.16);
  animation-delay: -7s;
  animation-duration: 22s;
}

.mist-c {
  width: 30vw;
  height: 30vw;
  top: 40%;
  left: 55%;
  background: rgba(196, 137, 106, 0.12);
  animation-delay: -11s;
  animation-duration: 26s;
}

.grain {
  position: absolute;
  inset: 0;
  opacity: 0.08;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 180px;
  mix-blend-mode: overlay;
}

@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(3%, -2%) scale(1.06); }
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* —— Brand —— */
.brand {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  padding: clamp(1rem, 3.5vh, 2.25rem) 1.5rem 0;
}

.brand-logo {
  display: block;
  width: min(32rem, 86vw);
  height: auto;
  animation: rise 1.1s var(--ease) both;
}

/* —— Stage —— */
.stage {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(2.5rem, 8vh, 5.5rem) 1.5rem 3rem;
}

.ecosystem {
  position: relative;
  width: min(1180px, 100%);
}

.bridges {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
  z-index: 0;
}

.bridge {
  stroke: var(--gold-soft);
  stroke-width: 0.7;
  stroke-dasharray: 3 7;
  opacity: 0;
  transition: opacity 0.45s ease;
}

.ecosystem.is-live .bridge {
  opacity: 0.55;
}

.clusters {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: space-between;
  gap: clamp(1.5rem, 4vw, 3.5rem);
  width: 100%;
}

/* —— Cluster shell —— */
.cluster {
  position: relative;
  flex: 0 0 auto;
  width: var(--field);
  height: var(--field);
  text-decoration: none;
  color: inherit;
  outline: none;
  transition: transform 0.55s var(--ease);
  animation: rise 1s var(--ease) both;
}

.cluster:nth-child(1) { animation-delay: 0.18s; }
.cluster:nth-child(2) { animation-delay: 0.28s; }
.cluster:nth-child(3) { animation-delay: 0.38s; }
.cluster:nth-child(4) { animation-delay: 0.48s; }

.cluster.is-away-left {
  transform: translateX(-14px) scale(0.96);
  opacity: 0.72;
}

.cluster.is-away-right {
  transform: translateX(14px) scale(0.96);
  opacity: 0.72;
}

.cluster.is-active {
  z-index: 3;
}

.field {
  position: absolute;
  inset: 50% auto auto 50%;
  width: var(--field);
  height: var(--field);
  transform: translate(-50%, -50%);
  display: grid;
  place-items: center;
  transition:
    width 0.55s var(--ease),
    height 0.55s var(--ease);
}

.field::before {
  content: "";
  position: absolute;
  inset: 12%;
  border-radius: 50%;
  background: radial-gradient(circle, var(--glow, rgba(196, 165, 116, 0.12)) 0%, transparent 70%);
  opacity: 0.45;
  filter: blur(18px);
  transition: opacity 0.5s ease, transform 0.55s var(--ease);
  pointer-events: none;
  z-index: 0;
}

.cluster:hover .field::before,
.cluster:focus-visible .field::before,
.cluster.is-active .field::before {
  opacity: 1;
  transform: scale(1.15);
}

[data-variant="laurel"] { --glow: rgba(196, 165, 116, 0.28); --accent: var(--gold); }
[data-variant="orbit"] { --glow: rgba(90, 143, 156, 0.3); --accent: var(--teal); }
[data-variant="generative"] { --glow: rgba(196, 137, 106, 0.28); --accent: var(--copper); }
[data-variant="halo"] { --glow: rgba(110, 142, 184, 0.3); --accent: var(--steel); }

.cluster:hover .field,
.cluster:focus-visible .field,
.cluster.is-active .field {
  width: var(--field-active);
  height: var(--field-active);
}

.drawing {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
}

.label {
  position: relative;
  z-index: 2;
  display: grid;
  place-items: center;
  text-align: center;
  width: 78%;
  min-height: 4.5rem;
}

.label-rest,
.label-active {
  grid-area: 1 / 1;
  font-family: var(--font-display);
  transition:
    opacity 0.4s ease,
    transform 0.5s var(--ease),
    letter-spacing 0.45s ease;
}

.label-rest {
  font-weight: 500;
  font-size: clamp(0.92rem, 1.35vw, 1.08rem);
  line-height: 1.25;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--pearl);
  opacity: 1;
  transform: translateY(0);
}

.label-active {
  font-weight: 500;
  font-size: clamp(1.05rem, 1.55vw, 1.28rem);
  line-height: 1.22;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--pearl);
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
}

.sub {
  display: block;
  margin-top: 0.75rem;
  font-family: var(--font-ui);
  font-size: clamp(0.72rem, 1.1vw, 0.82rem);
  font-weight: 300;
  letter-spacing: 0.06em;
  text-transform: none;
  color: var(--accent, var(--gold));
  line-height: 1.4;
  max-width: 16rem;
  margin-left: auto;
  margin-right: auto;
}

.cluster:hover .label-rest,
.cluster:focus-visible .label-rest,
.cluster.is-active .label-rest {
  opacity: 0;
  transform: translateY(-10px);
  letter-spacing: 0.22em;
}

.cluster:hover .label-active,
.cluster:focus-visible .label-active,
.cluster.is-active .label-active {
  opacity: 1;
  transform: translateY(0);
}

/* —— 01 Laurel · academy seal —— */
[data-variant="laurel"] .axis {
  stroke: rgba(183, 154, 115, 0.28);
  stroke-width: 0.6;
  stroke-linecap: round;
  transition: stroke 0.45s ease, stroke-dasharray 0.45s ease;
  stroke-dasharray: 1 0;
}

[data-variant="laurel"] .whisper {
  fill: rgba(138, 160, 180, 0.42);
  font-family: var(--font-ui);
  font-size: 5.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  transition: fill 0.4s ease, opacity 0.4s ease;
}

[data-variant="laurel"] .stem,
[data-variant="laurel"] .branch path:not(.stem) {
  fill: none;
  stroke: var(--line-soft);
  stroke-width: 0.85;
  stroke-linecap: round;
}

[data-variant="laurel"] .stem {
  stroke: rgba(196, 165, 116, 0.55);
  stroke-width: 0.95;
}

[data-variant="laurel"] .leaf {
  fill: rgba(196, 165, 116, 0.12);
  stroke: rgba(196, 165, 116, 0.45);
  stroke-width: 0.65;
}

[data-variant="laurel"] .branch-l,
[data-variant="laurel"] .branch-r {
  transform-origin: 120px 120px;
  transition: transform 0.6s var(--ease);
}

.cluster:hover[data-variant="laurel"] .branch-l,
.cluster:focus-visible[data-variant="laurel"] .branch-l,
.cluster.is-active[data-variant="laurel"] .branch-l {
  transform: translate(-10px, -2px) rotate(-5deg);
}

.cluster:hover[data-variant="laurel"] .branch-r,
.cluster:focus-visible[data-variant="laurel"] .branch-r,
.cluster.is-active[data-variant="laurel"] .branch-r {
  transform: translate(10px, -2px) rotate(5deg);
}

.cluster:hover[data-variant="laurel"] .leaf,
.cluster:focus-visible[data-variant="laurel"] .leaf,
.cluster.is-active[data-variant="laurel"] .leaf {
  fill: rgba(116, 141, 166, 0.32);
}

.cluster:hover[data-variant="laurel"] .axis,
.cluster:focus-visible[data-variant="laurel"] .axis,
.cluster.is-active[data-variant="laurel"] .axis {
  stroke: rgba(183, 154, 115, 0.55);
}

.cluster:hover[data-variant="laurel"] .whisper,
.cluster:focus-visible[data-variant="laurel"] .whisper,
.cluster.is-active[data-variant="laurel"] .whisper {
  fill: rgba(183, 154, 115, 0.7);
  opacity: 0;
}

/* —— 02 Orbit · precise machinery —— */
[data-variant="orbit"] .arc {
  fill: none;
  stroke: var(--line);
  stroke-width: 0.75;
  stroke-linecap: round;
  transition:
    stroke 0.45s ease,
    stroke-dashoffset 0.7s var(--ease),
    opacity 0.4s ease;
}

[data-variant="orbit"] .arc-a { stroke-dasharray: 180 40; }
[data-variant="orbit"] .arc-b { stroke-dasharray: 120 50; opacity: 0.7; }
[data-variant="orbit"] .arc-c { stroke-dasharray: 130 45; opacity: 0.75; }
[data-variant="orbit"] .arc-d {
  stroke: var(--teal-soft);
  stroke-width: 0.65;
  stroke-dasharray: 150 30;
}
[data-variant="orbit"] .arc-e,
[data-variant="orbit"] .arc-f {
  stroke: rgba(90, 143, 156, 0.4);
  stroke-width: 0.55;
  opacity: 0.55;
}
[data-variant="orbit"] .arc-g {
  stroke: rgba(90, 143, 156, 0.28);
  stroke-width: 0.5;
  stroke-dasharray: 4 8;
  opacity: 0.5;
}

[data-variant="orbit"] .micro {
  fill: rgba(90, 143, 156, 0.35);
  font-family: var(--font-ui);
  font-size: 6.5px;
  letter-spacing: 0.16em;
  opacity: 0.35;
  transition: opacity 0.4s ease, fill 0.4s ease;
}

[data-variant="orbit"] .tick {
  fill: rgba(245, 240, 225, 0.22);
  transition: fill 0.4s ease;
}

.cluster:hover[data-variant="orbit"] .arc,
.cluster:focus-visible[data-variant="orbit"] .arc,
.cluster.is-active[data-variant="orbit"] .arc {
  stroke: rgba(245, 240, 225, 0.5);
  stroke-dashoffset: -18;
  opacity: 1;
}

.cluster:hover[data-variant="orbit"] .micro,
.cluster:focus-visible[data-variant="orbit"] .micro,
.cluster.is-active[data-variant="orbit"] .micro {
  opacity: 1;
  fill: var(--teal);
}

.cluster:hover[data-variant="orbit"] .tick,
.cluster:focus-visible[data-variant="orbit"] .tick,
.cluster.is-active[data-variant="orbit"] .tick {
  fill: rgba(245, 240, 225, 0.7);
}

/* —— 03 Generative · forming mark —— */
[data-variant="generative"] .sketch {
  fill: none;
  stroke: var(--line-soft);
  stroke-width: 0.7;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: 0.45;
  transform-origin: 120px 120px;
  transition:
    transform 0.7s var(--ease),
    opacity 0.45s ease,
    stroke 0.45s ease;
}

[data-variant="generative"] .s1 { transform: rotate(-4deg) scale(1.02); opacity: 0.35; }
[data-variant="generative"] .s2 { transform: rotate(3deg) scale(0.96); }
[data-variant="generative"] .s3 { transform: rotate(-2deg) scale(1.04); opacity: 0.3; }
[data-variant="generative"] .s4 { transform: rotate(5deg) scale(0.93); opacity: 0.4; }
[data-variant="generative"] .s5 {
  stroke: var(--copper-soft);
  opacity: 0.55;
  transform: rotate(-1deg);
}

[data-variant="generative"] .frag {
  fill: rgba(245, 240, 225, 0.28);
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.08em;
  opacity: 0.4;
  transition: opacity 0.5s ease, fill 0.5s ease, transform 0.7s var(--ease);
}

[data-variant="generative"] .frag-b {
  font-style: italic;
  font-size: 13px;
}

[data-variant="generative"] .frag-c {
  font-family: var(--font-ui);
  font-size: 7px;
  letter-spacing: 0.28em;
}

[data-variant="generative"] .sem {
  fill: rgba(196, 137, 106, 0.4);
  transition: fill 0.45s ease, r 0.45s ease;
}

[data-variant="generative"] .sem-link {
  stroke: rgba(196, 137, 106, 0.22);
  stroke-width: 0.5;
  stroke-dasharray: 2 4;
  transition: stroke 0.45s ease, opacity 0.45s ease;
  opacity: 0.5;
}

.cluster:hover[data-variant="generative"] .sketch,
.cluster:focus-visible[data-variant="generative"] .sketch,
.cluster.is-active[data-variant="generative"] .sketch {
  transform: rotate(0deg) scale(1);
  opacity: 0.85;
  stroke: rgba(245, 240, 225, 0.55);
}

.cluster:hover[data-variant="generative"] .s5,
.cluster:focus-visible[data-variant="generative"] .s5,
.cluster.is-active[data-variant="generative"] .s5 {
  stroke: var(--copper);
  opacity: 1;
  stroke-width: 0.9;
}

.cluster:hover[data-variant="generative"] .frag,
.cluster:focus-visible[data-variant="generative"] .frag,
.cluster.is-active[data-variant="generative"] .frag {
  opacity: 0;
}

.cluster:hover[data-variant="generative"] .sem,
.cluster:focus-visible[data-variant="generative"] .sem,
.cluster.is-active[data-variant="generative"] .sem {
  fill: var(--copper);
}

.cluster:hover[data-variant="generative"] .sem-link,
.cluster:focus-visible[data-variant="generative"] .sem-link,
.cluster.is-active[data-variant="generative"] .sem-link {
  stroke: rgba(196, 137, 106, 0.5);
  opacity: 0.85;
  stroke-dasharray: none;
}

/* —— 04 Halo —— */
[data-variant="halo"] .soft-edge {
  fill: none;
  stroke: rgba(245, 240, 225, 0.2);
  stroke-width: 1.1;
  transition:
    stroke 0.5s ease,
    stroke-width 0.5s ease,
    opacity 0.45s ease;
}

[data-variant="halo"] .soft-edge-b {
  stroke: rgba(110, 142, 184, 0.35);
  stroke-width: 0.7;
  opacity: 0.7;
}

[data-variant="halo"] .haze {
  transition: transform 0.65s var(--ease), opacity 0.45s ease;
  transform-origin: 120px 120px;
}

[data-variant="halo"] .nodes {
  opacity: 0;
  transition: opacity 0.5s ease;
}

[data-variant="halo"] .nodes circle {
  fill: rgba(245, 240, 225, 0.65);
}

[data-variant="halo"] .nodes line {
  stroke: rgba(110, 142, 184, 0.4);
  stroke-width: 0.55;
}

[data-variant="halo"] .dust circle {
  fill: rgba(245, 240, 225, 0.25);
}

.cluster:hover[data-variant="halo"] .haze,
.cluster:focus-visible[data-variant="halo"] .haze,
.cluster.is-active[data-variant="halo"] .haze {
  transform: scale(1.18);
  opacity: 1;
}

.cluster:hover[data-variant="halo"] .soft-edge,
.cluster:focus-visible[data-variant="halo"] .soft-edge,
.cluster.is-active[data-variant="halo"] .soft-edge {
  stroke: rgba(245, 240, 225, 0.38);
  stroke-width: 1.35;
}

.cluster:hover[data-variant="halo"] .nodes,
.cluster:focus-visible[data-variant="halo"] .nodes,
.cluster.is-active[data-variant="halo"] .nodes {
  opacity: 1;
}

/* —— Responsive —— */
@media (max-width: 980px) {
  :root {
    --field: 200px;
    --field-active: 250px;
  }

  .clusters {
    gap: 1rem;
  }

  .label-rest {
    font-size: 0.8rem;
    letter-spacing: 0.12em;
  }

  .label-active {
    font-size: 0.92rem;
  }
}

@media (max-width: 720px) {
  :root {
    --field: 210px;
    --field-active: 260px;
  }

  .clusters {
    flex-direction: column;
    gap: 2.75rem;
  }

  .bridges {
    display: none;
  }

  .cluster.is-away-left,
  .cluster.is-away-right {
    transform: none;
    opacity: 1;
  }
}

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

  .ribbon-track {
    animation: none !important;
  }
}