:root {
  --bg: #02080d;
  --panel: #061118;
  --green: #00ef9d;
  --cyan: #00c9ff;
  --yellow: #ffd400;
  --pink: #ff3aa7;
  --purple: #bd55ff;
  --orange: #ff9700;
  --text: #f4f7f8;
  --muted: #a8b8be;
  font-family: "Segoe UI", Inter, system-ui, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100dvh;
  color: var(--text);
  background:
    radial-gradient(circle at 22% 18%, rgba(0,239,157,.10), transparent 30%),
    radial-gradient(circle at 80% 38%, rgba(189,85,255,.08), transparent 28%),
    linear-gradient(180deg, #02080d, #010609);
}

.portal-shell {
  width: min(1320px, calc(100% - 28px));
  margin: 0 auto;
  padding: clamp(28px, 5vw, 70px) 0 24px;
}

.hero {
  padding: clamp(22px, 4vw, 48px);
  border: 1px solid rgba(0,239,157,.25);
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(5,22,27,.96), rgba(2,10,15,.92));
}

.hero-brand {
  display: flex;
  align-items: center;
  gap: clamp(20px, 4vw, 48px);
}

.quantum-mark {
  width: clamp(130px, 18vw, 210px);
  flex: 0 0 auto;
}

.orbit {
  fill: none;
  stroke-width: 3;
  opacity: .8;
}
.orbit-a { stroke: var(--green); }
.orbit-b { stroke: var(--pink); transform: rotate(25deg); transform-origin: center; }
.orbit-c { stroke: var(--cyan); transform: rotate(-25deg); transform-origin: center; }
.core { fill: var(--green); }
.node-one { fill: var(--yellow); }
.node-two { fill: var(--pink); }
.node-three { fill: var(--cyan); }

.eyebrow {
  margin: 0 0 8px;
  color: var(--cyan);
  text-transform: uppercase;
  letter-spacing: .13em;
  font-size: .78rem;
  font-weight: 700;
}

h1 {
  margin: 0;
  color: var(--green);
  font-size: clamp(2.6rem, 7vw, 5.7rem);
  line-height: .95;
}

.hero h2 {
  margin: 14px 0 0;
  font-size: clamp(1.2rem, 2.6vw, 2rem);
  font-weight: 500;
}

.tagline {
  color: var(--yellow);
  letter-spacing: .12em;
  font-weight: 700;
}

.intro {
  max-width: 850px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 1.5vw, 1.16rem);
  line-height: 1.65;
}

.mode-section {
  padding: clamp(42px, 6vw, 74px) 0;
}

.section-heading {
  margin-bottom: 22px;
}

.step {
  margin: 0;
  color: var(--green);
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: .75rem;
}

.section-heading h2 {
  margin: 5px 0 0;
  font-size: clamp(1.8rem, 4vw, 3rem);
}

.mode-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.mode-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid rgba(0,239,157,.24);
  border-radius: 22px;
  background: rgba(4,16,22,.92);
}

.mode-visual {
  min-height: 245px;
  display: grid;
  place-items: center;
  background:
    radial-gradient(circle, rgba(0,239,157,.10), transparent 55%),
    linear-gradient(135deg, rgba(0,201,255,.03), transparent);
}

.mini-sphere {
  width: 170px;
  aspect-ratio: 1;
  position: relative;
  border: 2px solid rgba(0,239,157,.72);
  border-radius: 50%;
  box-shadow: inset 0 0 35px rgba(0,239,157,.14);
}

.axis {
  position: absolute;
  inset: 50% auto auto 50%;
  height: 2px;
  width: 220px;
  transform-origin: left;
}

.axis-z { background: var(--cyan); transform: rotate(-90deg) translateX(-50%); }
.axis-x { background: var(--yellow); transform: rotate(18deg) translateX(-50%); }
.axis-y { background: var(--pink); transform: rotate(-18deg) translateX(-50%); }

.mini-vector {
  position: absolute;
  left: 50%;
  bottom: 50%;
  width: 4px;
  height: 105px;
  background: var(--green);
  transform-origin: bottom;
  transform: rotate(32deg);
  box-shadow: 0 0 12px rgba(0,239,157,.7);
}

.five-spheres {
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
  padding: 40px;
}

.five-spheres span {
  width: 100%;
  max-width: 82px;
  aspect-ratio: 1;
  border: 2px solid var(--green);
  border-radius: 50%;
  box-shadow: inset 0 0 20px rgba(0,239,157,.14);
}

.five-spheres span:nth-child(2) { border-color: var(--yellow); }
.five-spheres span:nth-child(3) { border-color: var(--pink); }
.five-spheres span:nth-child(4) { border-color: var(--cyan); }
.five-spheres span:nth-child(5) { border-color: var(--purple); }

.mode-content {
  padding: 24px;
}

.mode-number {
  color: var(--green);
  font-size: .8rem;
  letter-spacing: .14em;
}

.title-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.mode-card h3 {
  margin: 8px 0;
  font-size: clamp(1.35rem, 2.4vw, 2rem);
}

.status {
  padding: 5px 8px;
  border: 1px solid rgba(255,212,0,.35);
  border-radius: 999px;
  color: var(--yellow);
  font-size: .7rem;
  white-space: nowrap;
}

.mode-card p,
.mode-card li {
  color: var(--muted);
  line-height: 1.55;
}

.mode-card ul {
  padding-left: 18px;
  margin-bottom: 24px;
}

.mode-button {
  display: inline-block;
  padding: 11px 17px;
  border: 1px solid var(--green);
  border-radius: 10px;
  color: var(--green);
  text-decoration: none;
  font-weight: 700;
}

.mode-button.secondary {
  border-color: var(--purple);
  color: #d9b3f6;
}

.journey {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: center;
  gap: 18px;
  padding: 22px;
  border: 1px solid rgba(0,201,255,.18);
  border-radius: 18px;
}

.journey-step {
  display: flex;
  align-items: center;
  gap: 13px;
}

.journey-step strong {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: rgba(0,239,157,.12);
  color: var(--green);
}

.journey-step span { font-weight: 700; }
.journey-step p { margin: 3px 0 0; color: var(--muted); font-size: .83rem; }
.journey-arrow { color: var(--green); }

footer {
  margin-top: 22px;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
  border-top: 1px solid rgba(0,239,157,.18);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-brand svg { width: 90px; height: 70px; }
.footer-brand line { stroke: #263541; stroke-width: 7; }
.footer-ring { fill: none; stroke: white; stroke-width: 10; }
.footer-core { fill: #101a2b; }
.dot-yellow { fill: var(--yellow); }
.dot-pink { fill: var(--pink); }
.dot-cyan { fill: var(--cyan); }
.dot-green { fill: #69ff00; }

.footer-brand div {
  display: flex;
  flex-direction: column;
}

.footer-brand span {
  margin-top: 5px;
  color: var(--cyan);
  font-size: .75rem;
}

.credits {
  color: var(--muted);
  text-align: right;
  font-size: .82rem;
}

.credits p { margin: 4px 0; }
.credits strong { color: var(--text); }

@media (max-width: 820px) {
  .hero-brand {
    flex-direction: column;
    align-items: flex-start;
  }

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

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

  .journey-arrow {
    transform: rotate(90deg);
    justify-self: center;
  }

  footer {
    flex-direction: column;
    align-items: flex-start;
  }

  .credits {
    text-align: left;
  }
}

@media (max-width: 520px) {
  .portal-shell {
    width: min(100% - 14px, 520px);
    padding-top: 8px;
  }

  .hero {
    padding: 20px 16px;
  }

  .five-spheres {
    gap: 6px;
    padding: 25px 12px;
  }

  .mode-content {
    padding: 18px;
  }

  .title-row {
    align-items: flex-start;
    flex-direction: column;
  }
}

.three-modes{grid-template-columns:repeat(3,1fr)}
@media(max-width:1050px){.three-modes{grid-template-columns:1fr}}